Introduction: Accurate diagnosis of thyrotoxicosis, a condition resulting from excessive thyroid hormone activity, is essential for appropriate management. However, access to diagnostic tools such as thyrotropin receptor antibody (TRAb) assays and thyroid ultrasonography remains limited in resource-constrained settings, highlighting the need for cost-effective alternatives. Recent studies suggest that the free triiodothyronine to free thyroxine (FT3/FT4) ratio may serve as a potential biomarker for differentiating the causes of thyrotoxicosis. Methodology: This cross-sectional study evaluated the FT3/FT4 ratio in newly diagnosed thyrotoxicosis patients aged ≥18 years recruited from Hospital Tengku Ampuan Rahimah, Hospital Banting, Klinik Kesihatan Pelabuhan Klang, and Klinik Kesihatan Pandamaran between February and December 2025. All participants underwent thyroid function testing (FT3, FT4, and TSH) and autoantibody assessment (TRAb and anti-thyroid peroxidase [anti-TPO]). Diagnostic performance of the FT3/FT4 ratio for Graves’ disease was assessed using receiver operating characteristic (ROC) curve analysis. Results: Fifty-eight patients were included, of whom 58.6% were diagnosed with Graves’ disease. Patients with Graves’ disease had significantly higher FT3 levels (median 16.8 pmol/L; IQR 10.9–25.7) compared to those with non-Graves’ thyrotoxicosis (median 8.3 pmol/L; IQR 5.3–13.5; p <0.001), with similar trends observed for FT4 levels (p <0.001). However, the FT3/ FT4 ratio did not differ significantly between groups (p >0.05), with an overall ROC AUC of 0.572, indicating poor discriminatory ability. Subgroup analysis based on FT4 levels improved performance; at FT4 <30 pmol/L, the FT3/FT4 ratio demonstrated 75.0% sensitivity, 91.7% specificity, and 87.5% diagnostic accuracy at a cutoff of 0.3445 (AUC = 0.813; 95% CI: 0.570–1.000; p = 0.069). No significant association was observed between the FT3/FT4 ratio and TRAb or anti-TPO. Conclusion The FT3/FT4 ratio has limited overall diagnostic utility but may provide adjunctive value in selected biochemical contexts, particularly in settings with limited access to immunological testing.
Diagnosis, Differential ; Thyroxine ; Triiodothyronine ; Thyrotoxicosis ; Cross-Sectional Studies

Introduction: Dopaminomas or dopamine-secreting pheochromocytomas are rare neuroendocrine tumors that frequently lack the classic paroxysmal symptoms of catecholamine excess (headache, sweating, palpitation). Diagnosing these tumors is exceptionally challenging when biochemical markers— specifically markedly elevated urinary dopamine—are interpreted in patients receiving exogenous Levodopa (L-DOPA) therapy, as the intake obscures clinical significance. Case: A 76-year-old male with ischemic heart disease, stage 4 chronic kidney disease, and new-onset hypertension was admitted for acute cholecystitis. Imaging studies incidentally revealed bilateral adrenal masses and demonstrated lipid-rich characteristics upon further evaluation with computed tomography (CT) adrenal washout. Biochemical evaluation revealed extreme elevations in 24-hour urinary dopamine (47,534 nmol/24 hours; normal <3,237) and 3-methoxytyramine (18.93 µmol/24 hours; normal <2.60), whereas downstream urinary noradrenaline (5.0 nmol/24 hours; normal 71.5–505.3), adrenaline (4.0 nmol/24 hours; normal 9.2–122.3), normetanephrine (0.22 µmol/24 hours; normal 0.88–2.88), and metanephrine (0.25 µmol/24 hours; normal 0.33–1.53) levels were all significantly below their respective reference ranges. The diagnosis was complicated by the patient’s concurrent use of L-DOPA/Benserazide for flupentixol-induced parkinsonism. L-DOPA is a direct precursor to dopamine; its administration can cause massive, false-positive elevations in urinary dopamine, mimicking a dopaminoma’s biochemical signature. However, the unique combination of profoundly high dopamine alongside suppressed downstream catecholamines and metanephrines suggested a true dopaminesecreting tumor—potentially secondary to dopamine beta-hydroxylase (DBH) deficiency—rather than drug interference. Conclusion This case illustrates the profound difficulty in diagnosing dopaminoma when exogenous L-DOPA therapy creates a near-identical biochemical profile. The diagnostic dilemma is further amplified by vague symptomatology, multiple comorbidities, and non-suggestive imaging. However, the finding of isolated dopamine hypersecretion with suppressed metanephrines serves as a critical clinical clue. This pattern points toward an intratumoral biosynthetic defect rather than drug interference. Clinicians must maintain a high index of suspicion and perform meticulous biochemical fractionation to identify these rare, dopamineisolated secreting tumors.
Dopamine ; Levodopa

Introduction: Thyroid stimulating hormone (TSH) suppression following differentiated thyroid carcinoma is widely recommended to reduce recurrence risk. However, this strategy assumes cardiovascular tolerance to supraphysiologic thyroid hormone exposure. In patients with advanced structural heart disease, this assumption may fail, exposing a critical limitation of guideline-directed TSH suppression. Case: We report a 71-year-old male with end-stage renal failure on hemodialysis and severe ischemic cardiomyopathy (ejection fraction 23%) who presented with acute decompensation characterized by dyspnea, rapid atrial fibrillation, and non–ST-elevation myocardial infarction. He had a history of papillary thyroid carcinoma treated with total thyroidectomy and radioactive iodine over 20 years prior and was maintained on levothyroxine 200 mcg daily for TSH suppression. Despite biochemically euthyroid indices (TSH 1.8 mIU/L, free thyroxine 4 17 pmol/L), he developed recurrent arrhythmia with heart failure decompensation. This case highlights a dissociation between biochemical euthyroidism and tissue-level thyrotoxicity in a structurally compromised myocardium. Papillary thyroid carcinoma after definitive therapy typically follows an indolent course with low short-term mortality. In contrast, in severe left ventricular dysfunction, excess thyroid hormone increases adrenergic sensitivity and myocardial oxygen demand, precipitating arrhythmia and ischemia. This risk is amplified in end-stage renal disease, where altered hormone handling renders biochemical indices less reliable. Conclusion Biochemical euthyroidism does not equate to physiological safety. In patients with advanced cardiovascular disease, thyroid hormone therapy should be titrated to cardiovascular tolerance rather than oncologic targets alone, and routine TSH suppression may be inappropriate.
Thyroxine ; Heart Failure ; Thyrotropin

Hematologic malignancies, including leukemia, lymphoma, and multiple myeloma, are hazardous diseases characterized by the uncontrolled proliferation of cancer cells. Dysregulated cell cycle resulting from genetic and epigenetic abnormalities constitutes one of the central events. Importantly, cyclin-dependent kinases (CDKs), complexed with their functional partner cyclins, play dominating roles in cell cycle control. Yet, efforts in translating CDK inhibitors into clinical benefits have demonstrated disappointing outcomes. Recently, mounting evidence highlights the emerging significance of WEE1 G2 checkpoint kinase (WEE1) to modulate CDK activity, and correspondingly, a variety of therapeutic inhibitors have been developed to achieve clinical benefits. Thus, WEE1 may become a promising target to modulate the abnormal cell cycle. However, its function in hematologic diseases remains poorly elucidated. In this review, focusing on hematologic malignancies, we describe the biological structure of WEE1, emphasize the latest reported function of WEE1 in the carcinogenesis, progression, as well as prognosis, and finally summarize the therapeutic strategies by targeting WEE1.
Humans ; Protein-Tyrosine Kinases/physiology* ; Hematologic Neoplasms/drug therapy* ; Cell Cycle Proteins/antagonists & inhibitors* ; Nuclear Proteins/antagonists & inhibitors* ; Cyclin-Dependent Kinases ; Molecular Targeted Therapy ; Animals

This study explores the effect and mechanism of Banxia Xiexin Decoction(BXD) in inhibiting colon cancer progression by reshaping tryptophan metabolism. Balb/c mice were assigned into control, model, low-dose BXD(BXD-L), and high-dose BXD(BXD-H) groups. Except the control group, the other groups were subcutaneously injected with CT26-Luc cells for the modeling of colon cancer, which was followed by the intervention with BXD. Small animal live imaging was employed to monitor tumor growth, and the tumor volume and weight were measured. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in mouse tumors. Immunohistochemistry was used to detect Ki67 expression in tumors. Immunofluorescence and flow cytometry were used to detect the infiltration and number changes of CD3~+/CD8~+ T cells in the tumor tissue. Enzyme-linked immunosorbent assay(ELISA) was employed to measure the levels of interferon-gamma(IFN-γ) and interleukin-2(IL-2) in tumors. Targeted metabolomics was employed to measure the level of tryptophan(Trp) in the serum, and the Trp content in the tumor tissue was measured. Western blot and RT-qPCR were employed to determine the protein and mRNA levels, respectively, of indoleamine 2,3-dioxygenase 1(IDO1), MYC proto-oncogene, and solute carrier family 7 member 5(SLC7A5) in the tumor tissue. Additionally, a co-culture model with CT26 cells and CD8~+ T cells was established in vitro and treated with the BXD-containing serum. The cell counting kit-8(CCK-8) assay was used to examine the viability of CT26 cells. The content of Trp in CT26 cells and CD8~+ T cells, as well as the secretion of IFN-γ and IL-2 by CD8~+ T cells, was measured. RT-qPCR was used to determine the mRNA levels of MYC and SLC7A5 in CT26 cells. The results showed that BXD significantly inhibited the tumor growth, reduced the tumor weight, and decreased the tumor volume in the model mice. In addition, the model mice showed sparse arrangement of tumor cells, varying degrees of patchy necrosis, and downregulated expression of Ki67 in the tumor tissue. BXD elevated the levels of IFN-γ and IL-2 in the tumor tissue, while upregulating the ratio of CD3~+/CD8~+ T cells and lowering the levels of Trp, IDO1, MYC, and SLC7A5. The co-culture experiment showed that BXD-containing serum reduced Trp uptake by CT26 cells, increased Trp content in CD8~+T cells, enhanced IL-2 and IFN-γ secretion of CD8~+T cells, and down-regulated the mRNA levels of MYC and SLC7A5 in CT26 cells. In summary, BXD can inhibit the MYC/SLC7A5 pathway to reshape Trp metabolism and adjust Trp uptake by CD8~+ T cells to enhance the cytotoxicity, thereby inhibiting the development of colon cancer.
Animals ; Tryptophan/metabolism* ; Colonic Neoplasms/pathology* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Mice, Inbred BALB C ; Humans ; Cell Line, Tumor ; Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism* ; Female ; Disease Progression ; Cell Proliferation/drug effects* ; Proto-Oncogene Mas ; Male

This study aims to observe the mind-tranquilizing effect of Fushen Decoction on mice and investigate its effects on the 5-hydroxytryptamine(5-HT) system and γ-aminobutyric acid(GABA) in the brain of the mouse model of 4-chloro-DL-phenylalanine(PCPA)-induced insomnia. ICR mice were administrated with coffee(1 g·kg~(-1)) for 3 days, and the effects of Fushen Decoction(10, 20, and 40 g·kg~(-1)) on the autonomic activities of normal mice and coffee-treated mice were observed. Furthermore, the effects of Fushen Decoction on the autonomic activity and sleep induced by a suprathreshold dose of pentobarbital sodium in the mouse model of PCPA(350 mg·kg~(-1) for 3 consecutive days)-induced insomnia were observed. The levels of tryptophan hydroxylase(TPH), 5-hydroxytryptophan(5-HTP), and 5-HT in the serum, as well as those of 5-HTP and 5-HT in the brain stem, hippocampus, and cortex, were measured by enzyme-linked immunosorbent assay(ELISA). The fluorescence intensity of 5-HT in the raphe nucleus, hippocampus, and cortex was measured by the immunofluorescence method. The protein levels of tryptophan hydroxylase-2(TPH2) and 5-HT_(1A) receptor(5-HT_(1A)R) in the brain stem, hippocampus, and cortex were measured by Western blot. The levels of GABA in the hypothalamus, hippocampus, and cortex were measured by ELISA and immunohistochemistry methods. The results showed that Fushen Decoction(20, 40 g·kg~(-1)) reduced the number of autonomous activities in normal mice, coffee-treated mice, and the mouse model of PCPA-induced insomnia, and prolonged the duration of sleep induced by a suprathreshold dose of pentobarbital sodium in the mouse model. Fushen Decoction(20, 40 g·kg~(-1)) elevated the levels of TPH, 5-HTP, and 5-HT in the serum, and TPH2, 5-HTP, 5-HT, and 5-HT_(1A)R in the brain stem, hippocampus, and cortex, and up-regulated GABA expression in the hypothalamus, cortex, and hippocampus of the mouse model of PCPA-induced insomnia. In conclusion, Fushen Decoction(20, 40 g·kg~(-1)) exerted a mind-tranquilizing effect on mice by up-regulating the expression of TPH2, enhancing the 5-HT system, and elevating the GABA level in the brain.
Animals ; Serotonin/genetics* ; Sleep Initiation and Maintenance Disorders/genetics* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Mice, Inbred ICR ; gamma-Aminobutyric Acid/genetics* ; Disease Models, Animal ; Fenclonine/adverse effects* ; Tryptophan Hydroxylase/genetics* ; Brain/metabolism* ; Sleep/drug effects* ; Humans ; 5-Hydroxytryptophan/metabolism*

Nigella sativa L. seeds have been traditionally utilized in Chinese folk medicine for centuries to treat vitiligo. This study revealed that the ethanolic extract of Nigella sativa L. (HZC) enhances melanogenesis and mitigates oxidative stress-induced cellular senescence and dysfunction in melanocytes. In accordance with established protocols, the ethanol fraction from Nigella sativa L. seeds was extracted, concentrated, and lyophilized to evaluate its herbal effects via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, tyrosinase activity evaluation, measurement of cellular melanin contents, scratch assays, senescence-associated β-galactosidase (SA-β-gal) staining, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis for expression profiling of experimentally relevant proteins. The results indicated that HZC significantly enhanced tyrosinase activity and melanin content while notably increasing the protein expression levels of Tyr, Mitf, and gp100 in B16F10 cells. Furthermore, HZC effectively mitigated oxidative stress-induced cellular senescence, improved melanocyte condition, and rectified various functional impairments associated with melanocyte dysfunction. These findings suggest that HZC increases melanin synthesis in melanocytes through the activation of the MAPK, PKA, and Wnt signaling pathways. In addition, HZC attenuates oxidative damage induced by H₂O₂ therapy by activating the nuclear factor E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway and enhancing the activity of downstream antioxidant enzymes, thus preventing premature senescence and dysfunction in melanocytes.
Oxidative Stress/drug effects* ; Melanocytes/cytology* ; Cellular Senescence/drug effects* ; Nigella sativa/chemistry* ; Plant Extracts/pharmacology* ; Seeds/chemistry* ; Mice ; Animals ; Melanins/metabolism* ; Monophenol Monooxygenase/metabolism* ; Humans

Eight previously undescribed lanostane triterpenoids, including five nortriterpenoids with 26 carbons, ganothenoids A-E (1-5), and three lanostanoids, ganothenoids F-H (6-8), along with 24 known ones (9-32), were isolated from the fruiting bodies of Ganodrma theaecolum. The structures of the novel compounds were elucidated using comprehensive spectroscopic methods, including electronic circular dichroism (ECD) and nuclear magnetic resonance (NMR) calculations. Compounds 1-32 were assessed for their neuroprotective effects against H₂O₂-induced damage in human neuroblastoma SH-SY5Y cells, as well as their inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase. Compound 4 demonstrated the most potent neuroprotective activity against H₂O₂-induced oxidative stress by suppressing G₀/G₁ phase cell cycle arrest, reducing reactive oxygen species (ROS) levels, and inhibiting cell apoptosis through modulation of B-cell lymphoma 2 protein (Bcl-2) and Bcl-2 associated X-protein (Bax) protein expression. Compounds 26, 12, and 28 exhibited PTP1B inhibitory activities with IC₅₀ values ranging from 13.92 to 56.94 μmol·L^-1, while compound 12 alone displayed significant inhibitory effects on α-glucosidase with an IC₅₀ value of 43.56 μmol·L^-1. Additionally, enzyme kinetic analyses and molecular docking simulations were conducted for compounds 26 and 12 with PTP1B and α-glucosidase, respectively.
Humans ; Fruiting Bodies, Fungal/chemistry* ; Triterpenes/isolation & purification* ; Neuroprotective Agents/isolation & purification* ; Protein Tyrosine Phosphatase, Non-Receptor Type 1/metabolism* ; Ganoderma/chemistry* ; Apoptosis/drug effects* ; Hypoglycemic Agents/isolation & purification* ; Molecular Structure ; alpha-Glucosidases/metabolism* ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Oxidative Stress/drug effects* ; Hydrogen Peroxide/toxicity* ; Molecular Docking Simulation

Anthoceros angustus Steph. is rich in phenolic acids such as rosmarinic acid (RA). Phenylalanine ammonia-lyase (PAL) is an entry enzyme in the phenylpropanoid pathway of plants, playing an important role in the biosynthesis of RA. To investigate the important role of PAL in rosmarinic acid synthesis, two PAL genes (designated as AanPAL1 and AanPAL2) were cloned from A. angustus, encoding 755 and 753 amino acid residues, respectively. The AanPAL deduced amino acid sequences contain the conserved domains of PAL and the core active amino acid residues Ala-Ser-Gly. The phylogenetic analysis indicated that AanPAL1 and AanPAL2 were clustered with PALs from bryophytes and ferns and had the shortest evolutionary distance with the PALs from Physcomitrella patens. Quantitative real-time PCR results showed that the expression of AanPAL1 and AanPAL2 was induced by exogenous methyl jasmonate (MeJA). HPLC results showed that the MeJA treatment significantly increased the accumulation of RA. AanPAL1 and AanPAL2 were expressed in Escherichia coli and purified by histidine-tag affinity chromatography. The recombinant proteins catalyzed the conversion of L-phenylalanine to generate trans-cinnamic acid with high efficiency, with the best performance at 50 ℃ and pH 8.0. The K_m and k_cat of AanPAL1 were 0.062 mmol/L and 4.35 s^-1, and those of AanPAL2 were 0.198 mmol/L and 14.48 s^-1, respectively. The specific activities of AanPAL1 and AanPAL2 were 2.61 U/mg and 8.76 U/mg, respectively. The two enzymes had relatively poor thermostability but good pH stability. The high activity of AanPAL2 was further confirmed via whole-cell catalysis with recombinant E. coli, which could convert 1 g/L L-phenylalanine into trans-cinnamic acid with a yield of 100% within 10 h. These results give insights into the regulatory role of AanPAL in the biosynthesis of RA in A. angustus and provide candidate enzymes for the biosynthesis of cinnamic acid.
Phenylalanine Ammonia-Lyase/metabolism* ; Cloning, Molecular ; Cinnamates/metabolism* ; Recombinant Proteins/metabolism* ; Rosmarinic Acid ; Depsides/metabolism* ; Escherichia coli/metabolism* ; Amino Acid Sequence ; Plant Proteins/metabolism* ; Phylogeny ; Acetates/pharmacology* ; Cyclopentanes ; Oxylipins

L-tyrosine is one of the 20 amino acids that make up proteins and is an essential amino acid for mammals, often used as a nutritional supplement. The conventional methods for synthesizing L-tyrosine have some problems such as the production of many by-products, high requirements for production conditions, and environmental pollution. In this study, we designed and constructed a multi-enzyme cascade for the synthesis of L-tyrosine with alanine, glutamate, ammonium chloride, and phenol as substrates. Initially, the sources of glutamate oxidase, alanine aminotransferase, and tyrosine phenol lyase were screened and analyzed, which was followed by the identification of the rate-limiting enzyme in the reaction process. A colorimetric screening method was established, and the rate-limiting enzyme DbAlaA was engineered to enhance its activity by 40.0%. Subsequently, the reaction conditions, including temperature, pH, cell concentration, and surfactant and coenzyme dosages, were optimized. After optimization, the yield of L-tyrosine reached 9.93 g/L, with a alanine conversion rate of 54.90%. Finally, a feed-batch fermentation strategy was adopted, and the yield of L-tyrosine reached 56.07 g/L after 24 h, with a alanine conversion rate of 65.22%. This study provides a reference for the whole-cell catalytic synthesis of L-tyrosine and its industrialization.
Tyrosine/biosynthesis* ; Escherichia coli/metabolism* ; Tyrosine Phenol-Lyase/genetics* ; Multienzyme Complexes/metabolism* ; Fermentation