A simple, rapid and sensitive sandwich immunoassay based on poly(N-isopropylacrylamide) for the detection of alpha-fetoprotein.

Alpha-fetoprotein (AFP), as a tumor marker, plays a vital role in the diagnosis of liver cancer. In this work, a novel sandwich immunoassay based on a thermosensitive polymer, poly(N-isopropylacrylamide) (PNIPAM), was developed for the detection of AFP. This immunoassay could realize one-step rapid reaction within 1 h, and facilitate the separation of the target molecules by incorporating PNIPAM. In this method, a conjugate of PNIPAM and capture antibody (Ab1) was successfully synthesized as a capture probe and the synthetic method of PNIPAM-Ab1 was simple, while the detection antibody (Ab2) was labeled with fluorescein isothiocyanate (FITC) to form a fluorescent detection probe. By employing a sandwich immunoassay, the method achieved quantitative determination of AFP, exhibiting a wide linear range from 5 ng/mL to 200 ng/mL and a low detection limit of 2.44 ng/mL. Furthermore, it was successfully applied to the analysis of spiked human serum samples and the screening of patients with hepatic diseases in clinical samples, indicating its potential application prospect in the diagnosis of liver cancer.

The risk of concurrent malignancies in patients with multiple endocrine neoplasia type 1: insights into clinical characteristics of those with multiple endocrine neoplasia type 1.

OBJECTIVE: Summarize and analyze the characteristics of patients with Multiple Endocrine Neoplasia type 1 (MEN-1) who were diagnosed with malignant tumors that do not belong to MEN-1 components. METHODS: Clinical data from patients with MEN-1 who visited Peking Union Medical College Hospital between April 2012 and April 2022 were collected. We compared the clinical characteristics of patients with malignant tumors outside of their MEN-1 components to those without additional tumors. MEN-1 gene testing was performed on most of these patients using Sanger sequencing, whole-exome sequencing, or MLPA. RESULTS: A total of 221 MEN-1 patients were diagnosed, of which 23 (10.40%) were found to have malignant tumors that did not belong to MEN-1 components, including papillary thyroid carcinoma (PTC) (4.52%), breast cancer (1.81%), urologic neoplasms (1.35%), primary hepatic carcinoma (PCC) (0.09%), meningeal sarcoma (0.05%), glioblastoma (0.05%), cervical cancer (0.05%), and lung carcinoma (0.05%). MEN-1 gene mutations were identified in 11 patients, including missense mutations, frameshift mutations, and splice mutations. The prevalence of each endocrine neoplasm, particularly gastroenteropancreatic neuroendocrine tumor, was higher in MEN-1 patients with other malignant tumors compared to MEN-1 patients without malignant tumors. CONCLUSION: Our retrospective study revealed a higher incidence of non-MEN-1 component malignant tumors in MEN-1 patients, especially breast cancer, PTC, and urologic neoplasms. These patients also exhibit more severe clinical phenotypes of MEN-1.

Chemotherapy effect on myocardial fibrosis markers in patients with gynecologic cancer and low cardiovascular risk.

Background: Patients with gynecologic cancers experience side effects of chemotherapy cardiotoxicity. We aimed to quantify cardiac magnetic resonance (CMR) markers of myocardial fibrosis in patients with gynecologic cancer and low cardiovascular risk who undergo chemotherapy. Methods: This study is part of a registered clinical research. CMR T1 mapping was performed in patients with gynecologic cancer and low cardiovascular risk undergoing chemotherapy. The results were compared with those of age-matched healthy control subjects. Results: 68 patients (median age = 50 years) and 30 control subjects were included. The median number of chemotherapy cycles of patients was 9.0 (interquartile range [IQR] 3.3-17.0). Extracellular volume fraction (ECV) (27.2% ± 2.7% vs. 24.5% ± 1.7%, P < 0.001) and global longitudinal strain (-16.2% ± 2.8% vs. -17.4% ± 2.0%, P = 0.040) were higher in patients compared with controls. Patients with higher chemotherapy cycles (>6 cycles) (n=41) had significantly lower intracellular mass indexed (ICMi) compared with both patients with lower chemotherapy cycles (≤6 cycles) (n=27) (median 27.44 g/m2 [IQR 24.03-31.15 g/m2] vs. median 34.30 g/m2 [IQR 29.93-39.79 g/m2]; P = 0.002) and the control group (median 27.44 g/m2 [IQR 24.03-31.15 g/m2] vs. median 32.79 g/m2 [IQR 27.74-35.76 g/m2]; P = 0.002). Patients with two or more chemotherapy regimens had significantly lower ICMi compared with both patients with one chemotherapy regimen (27.45 ± 5.16 g/m2 vs. 33.32 ± 6.42 g/m2; P < 0.001) and the control group (27.45 ± 5.16 g/m2 vs. 33.02 ± 5.52 g/m2; P < 0.001). The number of chemotherapy cycles was associated with an increase in the ECV (Standard regression coefficient [ß] = 0.383, P = 0.014) and a decrease in the ICMi (ß = -0.349, P = 0.009). Conclusion: Patients with gynecologic cancer and low cardiovascular risk who undergo chemotherapy have diffuse extracellular volume expansion, which is obvious with the increase of chemotherapy cycles. Myocyte loss may be part of the mechanism in patients with a higher chemotherapy load. Clinical trial registration: http://www.chictr.org.cn, identifier ChiCTR-DDD-17013450.

Primary dedifferentiated chondrosarcoma of the lung with a 4-year history of breast cancer: A case report.

BACKGROUND: Primary dedifferentiated chondrosarcoma (DDCS) of the lung is extremely rare and has a poor prognosis, especially in patients with a history of carcinomas and related treatment. Herein, we report a case of primary DDCS of the lung in a patient with a 4-year history of breast cancer and related treatment. CASE SUMMARY: A 49-year-old woman was admitted to our hospital with complaints of headache, dizziness, slurred speech, and dyskinesia in May 2021. Computed tomography (CT) examinations showed multiple nodules in the brain, vertebral body, and both lungs with multiple enlarged lymph nodes in the right hilum and mediastinum, which were considered metastases of breast cancer. No obvious mass was discovered in the right hilum. After several months of related administration, the patient's headache disappeared, and her condition improved. However, new problems of asthma, dyspnea, cough, and restricted activity appeared in late November 2021. Although the CT scan indicated that the lesions in the brain, lung, and vertebral body had shrunk or disappeared, a soft tissue density lesion appeared in her right hilum and blocked the bronchial lumen. To relieve her dyspnea, part of the mass was resected, and a stent was placed via fiberoptic bronchoscopy. Following a complete pathological examination of the tumor, it was confirmed to be a primary DDCS of the lung. The patient then received two rounds of systemic chemotherapy with a regimen of cisplatin + ifosfamide + doxorubicin hydrochloride liposome, palliative radiotherapy for the tumor in her right lung, and four cycles of systemic chemotherapy and targeted therapy with a regimen of temozolomide combined with bevacizumab successively. She was in stable condition after the completion of the systemic chemotherapy and targeted therapy but underwent rapid progression after lung radiotherapy. The CT examinations showed multiple nodules in the brain and in both lungs, and the tumor in the right hilum was increased in size. CONCLUSION: This case revealed a rare primary DDCS of the lung with a medical history of breast cancer, meaning a worse prognosis and making it more difficult to treat.

Concurrent mutations of germline GPR101 and somatic USP8 in a pediatric giant pituitary ACTH adenoma: a case report.

BACKGROUND: Cushing's disease (CD) is rare in pediatric patients. It is characterized by elevated plasma adrenocorticotropic hormone (ACTH) from pituitary adenomas, with damage to multiple systems and development. In recent years, genetic studies have shed light on the etiology and several mutations have been identified in patients with CD. CASE PRESENTATION: A girl presented at the age of 10 years and 9 months with facial plethora, hirsutism and acne. Her vision and eye movements were impaired. A quick weight gain and slow growth were also observed. Physical examination revealed central obesity, moon face, buffalo hump, supra-clavicular fat pads and bruising. Her plasma ACTH level ranged between 118 and 151 pg/ml, and sella enhanced MRI showed a giant pituitary tumor of 51.8 × 29.3 × 14.0 mm. Transsphenoidal pituitary debulk adenomectomy was performed and immunohistochemical staining confirmed an ACTH-secreting adenoma. Genetic analysis identified a novel germline GPR101 (p.G169R) and a somatic USP8 (p. S719del) mutation. They were hypothesized to impact tumor growth and function, respectively. CONCLUSIONS: We reported a rare case of pediatric giant pituitary ACTH adenoma and pointed out that unusual concurrent mutations might contribute to its early onset and large volume.

The Diverse Analysis Identifies Mutated KRAS Associated With Radioresistance in Non-Small Cell Lung Cancer.

Background: To analyze the relationship between V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) status and radioresistance in non-small cell lung cancer (NSCLC), we identified potential genotypic differences and pathways involved. Methods: We retrospectively analyzed epidermal growth factor receptor (EGFR) and KRAS status in patients undergoing definitive radiotherapy for NSCLC between 2004 and 2018. Cox proportional hazard models were used to evaluate local progression-free survival (LPFS). Using clonogenic survival and measurement of γH2AX foci, we analyzed the difference in radiosensitivity between NSCLC cell lines with different KRAS status. The Cancer Genome Atlas (TCGA) analysis was used to explore the potential pathways involved. Results: The results showed that of the 286 patients identified, 68 (24%) had local tumor progression (mean ± standard deviation (SD), 27 ± 17.4 months); of these patients, KRAS mutations were found in 14 (23%), and KRAS status was associated with LPFS. After adjusting for concurrent chemotherapy, gross tumor volume, and mutation status in multivariate analysis, KRAS mutation was associated with shorter LPFS (hazard ratio: 1.961; 95% confidence interval: 1.03 - 2.17; P = 0.032). KRAS mutation showed higher radioresistance in vitro. TCGA data showed that the ERK1/2 pathway, phosphatidylinositol I3 kinase (PI3K)/mTOR, p38 MAPK pathway, cell cycle checkpoint signaling, DNA damage, repair pathways, and EGFR/PKC/AKT pathway were differentially expressed in patients with KRAS mutations or cell lines compared with their expression in the wild-type group. Conclusions: Diverse analyses identified that KRAS mutation was associated with radioresistance in NSCLC. KRAS mutation status may be helpful as a biomarker of radioresistance and a potential target to increase radiosensitivity.

Appendiceal Neuroendocrine Tumor Is a Rare Cause of Ectopic Adrenocorticotropic Hormone Syndrome With Cyclic Hypercortisolism: A Case Report and Literature Review.

OBJECTIVE: Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is a condition of hypercortisolism caused by non-pituitary tumors secreting ACTH. Appendiceal neuroendocrine tumor as a rare cause of ectopic ACTH syndrome was reported scarcely. We aimed to report a patient diagnosed with EAS caused by an appendiceal neuroendocrine tumor and summarized characteristics of these similar cases reported before. CASE REPORT AND LITERATURE REVIEW: We reported a case with Cushing's syndrome who was misdiagnosed as pituitary ACTH adenoma at first and accepted sella exploration. Serum and urinary cortisol decreased, and symptoms were relieved in the following 4 months after surgery but recurred 6 months after surgery. The abnormal rhythm of plasma cortisol and ACTH presented periodic secretion and seemingly rose significantly after food intake. EAS was diagnosed according to inferior petrosal sinus sampling (IPSS). Appendiceal mass was identified by 68Ga-DOTA-Tyr3-octreotate (DOTATATE)-PET-CT and removed. The pathological result was consistent with appendiceal neuroendocrine tumor with ACTH (+). The literature review demonstrated 7 cases diagnosed with EAS caused by appendiceal neuroendocrine tumor with similarities and differences. CONCLUSION: The diagnosis of an ectopic ACTH-producing tumor caused by the appendiceal neuroendocrine tumor can be a challenging procedure. Periodic ACTH and cortisol secretion may lead to missed diagnosis and misdiagnosis. IPSS is crucial in the diagnosis of EAS and 68Ga-DOTATATE-PET-CT plays an important role in the identification of lesions.

Long non-coding RNAs as epigenetic mediator and predictor of glioma progression, invasiveness, and prognosis.

Gliomas are aggressive brain tumors with high mortality rate. Over the past several years, non-coding RNAs, specifically the long non-coding RNAs (lncRNAs), have emerged as biomarkers of considerable interest. Emerging data reveals distinct patterns of expressions of several lncRNAs in the glioma tissues, relative to their expression in normal brains. This has led to the speculation for putative exploitation of lncRNAs as diagnostic biomarkers as well as biomarkers for targeted therapy. With a focus on lncRNAs that have shown promise as epigenetic biomarkers in the proliferation, migration, invasion, angiogenesis and metastasis in various glioma models, we discuss several such lncRNAs. The data from cell line / animal model-based studies as well as analysis from human patient samples is presented for the most up-to-date information on the topic. Overall, the information provided herein makes a compelling case for further evaluation of lncRNAs in clinical settings.

Choriocarcinoma misdiagnosed as cerebral hemangioma: A case report.

BACKGROUND: Choriocarcinoma is a subtype of gestational trophoblastic disease, gestational trophoblastic neoplasia. Patients with brain metastasis are rare and information on the optimal treatment and patient outcome is limited. In order to improve the prognosis of this disease, accurate and timely treatments are very important for the patient of brain metastasis by choriocarcinoma. CASE SUMMARY: A 17-year-old unmarried girl was misdiagnosed with a cerebral hemangioma with intracranial hemorrhage in a local hospital after presentation with severe head pain. She underwent craniotomy three times for treatment. The pathological results of posterior intracranial hematoma showed choriocarcinoma, and the patient was diagnosed as choriocarcinoma (21 points in stage IV). After uterine artery embolization, etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine chemotherapy for 7 cycles, and whole brain radiotherapy, the patient achieved remission. She has been followed for 2 years with no signs of tumor recurrence. CONCLUSION: For female patients of childbearing age with an intracranial hematoma, the possibility of brain metastasis by choriocarcinoma should be considered. It is necessary to obtain a detailed history, including menstruation, beginning age of first sex, contraception, etc. The level of ß-human chorionic gonadotropin should be tested at the beginning, and a stratified treatment should be administered according to the International Federation of Gynecology and Obstetrics staging and World Health Organization prognostic scoring systems.

Recycling Polymeric Solid Wastes for Energy-Efficient Water Purification, Organic Distillation, and Oil Spill Cleanup.

Conventional approaches (e.g., pyrolysis) for managing waste polymer foams typically require highly technical skills and consume large amounts of energy resources. This paper presents an ultrafacile, cost-effective, and highly efficient alternative method for recycling waste packaging and cleaning foam (e.g., polymelamine-formaldehyde foam). The designed solar absorber, a polypyrrole-coated melamine foam (PMF), features a highly porous structure, excellent mechanical strength, low thermal conductivity, and rapid water transport capacity. These exceptional properties render the PMF suitable for multiple applications, including energy-efficient solar-powered water purification, ethanol distillation, and oil absorption. In water purification, the PMF yields a solar-thermal conversion efficiency as high as 87.7%, stability that is maintained for more than 35 operation cycles, and antifouling capabilities (when purifying different water types). In solar distillation, the PMF achieves a concentration increase up to 75 vol% when distilling a 10 vol% ethanol solution. In oil absorption, the PMF offers an oil-absorption capacity of ≈70 g g-1 with only a 7% loss in capacity after 100 absorbing-squeezing cycles. Thus, systems combining solar energy with various waste foams are highly promising as durable, renewable, and portable systems for water purification, organic distillation, and oil absorption, especially in remote regions or emergency situations.

Pathological features of COVID-19-associated lung injury: a preliminary proteomics report based on clinical samples.

The COVID-19 pandemic has emerged as a global health emergency due to its association with severe pneumonia and relative high mortality. However, the molecular characteristics and pathological features underlying COVID-19 pneumonia remain largely unknown. To characterize molecular mechanisms underlying COVID-19 pathogenesis in the lung tissue using a proteomic approach, fresh lung tissues were obtained from newly deceased patients with COVID-19 pneumonia. After virus inactivation, a quantitative proteomic approach combined with bioinformatics analysis was used to detect proteomic changes in the SARS-CoV-2-infected lung tissues. We identified significant differentially expressed proteins involved in a variety of fundamental biological processes including cellular metabolism, blood coagulation, immune response, angiogenesis, and cell microenvironment regulation. Several inflammatory factors were upregulated, which was possibly caused by the activation of NF-κB signaling. Extensive dysregulation of the lung proteome in response to SARS-CoV-2 infection was discovered. Our results systematically outlined the molecular pathological features in terms of the lung response to SARS-CoV-2 infection, and provided the scientific basis for the therapeutic target that is urgently needed to control the COVID-19 pandemic.

Antimicrobial peptide AR-23 derivatives with high endosomal disrupting ability enhance poly(l-lysine)-mediated gene transfer.

BACKGROUND: pH-sensitive peptides are a relatively new strategy for conquering the poor endosomal release of cationic polymer-mediated transfection. Modification of antimicrobial peptides by exchanging positively-charged residues with negatively-charged glutamic acid residues (Glu) greatly improves its lytic activity at the endosomal pH, which could improve cationic polymer-mediated transfection. METHODS: In the present study, we investigated the effect of the number of Glu substituted for positively-charged residues on the endosomal escape activity of AR-23 and the ability of mutated AR-23 with respect to enhancing cationic polymer-mediated transfection. Three analogs were synthesized by replacing the positively-charged residues in the AR-23 sequence with Glu one-by-one. RESULTS: The pH-sensitive lysis ability of the peptides, the effect of peptides on the physicochemical characteristics, the intracellular trafficking, the transfection efficiency and the cytotoxicity of the polyplexes were determined. Increased lytic activity of peptides was observed with the increased number of Glu replacement in the AR-23 sequence at acidic pH. The number of Glu substituted for positively-charged residues of AR-23 dramatically affects its lysis ability at neutral pH. Triple-Glu substitution in the AR-23 sequence greatly improved poly(l-lysine)-mediated gene transfection efficiency at the same time as maintaining low cytotoxicity. CONCLUSIONS: The results indicate that replacement of positively-charged residues with sufficient Glu residues may be considered as a method for designing pH-sensitive peptides, which could be applied as potential enhancers for improving cationic polymer-mediated transfection.

Fabrication of Micro Ultrasonic Powder Molding Polypropylene Part with Hydrophobic Patterned Surface.

Constructing regular micro-structures with certain geometric characteristics on the surface of the polymer part can obtain some specific functions. Micro ultrasonic powder molding (micro-UPM) is an efficient processing technique for the fabrication of well-filled micro-structured Polypropylene (PP) parts. The micro-structure array on the surface of the core insert was obtained by low speed wire electrical discharge machining (WEDM-LS). PP polymer surfaces with micro-structured patterns were successfully replicated from the core insert surface after micro-UPM. By studying the detailed topography characterizations of micro-structured PP parts, the effects of processing parameters (ultrasonic energy, welding pressure and holding time) on the micro-structured filling show that when PP polymer was formed under the conditions of 1000 J, 115 kPa and 8 s during micro-UPM, well-filled micro-structured parts can be obtained. Besides, without low surface energy coating modification, the water contact angles (WCAs) of micro-structured PP parts increased from 85.3° to 146.8°, indicating that the wettability of the surface can be changed by replicating the micro-structure on PP parts after micro-UPM.

Heparanase Facilitates PMA-Induced Megakaryocytic Differentiation in K562 Cells via Interleukin 6/STAT3 Pathway.

Heparanase (HPSE) is an endo-ß-D-glucuronidase that cleaves heparan sulfate and hence participates in remodeling of the extracellular matrix, leading to release of cytokines that are immobilized by binding to heparan sulfate proteoglycans (HSPGs), and consequently activating signaling pathways. This function of HPSE is correlated to its expression level that is normally very low in majority of the tissues. Exceptionally, human platelets express high level of HPSE, suggesting a unique physiological role in this cell. Using K562 cell line, we found a progressive increase of HPSE during the megakaryocytic differentiation. Analysis of a series of megakaryocytic differentiation-related heparin-binding proteins (HBPs) in the cell culture medium revealed an exclusive positive correlation between the level of interleukin 6 (IL-6) and HPSE expression. IL-6 modulated megakaryocytic differentiation through activation of STAT3. Further, we demonstrated that overexpression of HPSE potentiates megakaryocytic differentiation, whereas elimination of HPSE led to a delayed differentiation. This function of HPSE is associated with its activity, as overexpression of inactive HPSE had no effect on IL-6 production and megakaryocytic differentiation. The role of HPSE is further supported by the observation in an umbilical cord blood CD34+ cells megakaryocytic differentiation model. Our data propose a novel role for HPSE in platelets production by a HPSE/IL-6/STAT3 positive feedback loop that specifically regulates megakaryocytes maturation.

RNF34 functions in immunity and selective mitophagy by targeting MAVS for autophagic degradation.

Viral infection triggers the formation of mitochondrial antiviral signaling protein (MAVS) aggregates, which potently promote immune signaling. Autophagy plays an important role in controlling MAVS-mediated antiviral signaling; however, the exact molecular mechanism underlying the targeted autophagic degradation of MAVS remains unclear. Here, we investigated the mechanism by which RNF34 regulates immunity and mitophagy by targeting MAVS. RNF34 binds to MAVS in the mitochondrial compartment after viral infection and negatively regulates RIG-I-like receptor (RLR)-mediated antiviral immunity. Moreover, RNF34 catalyzes the K27-/K29-linked ubiquitination of MAVS at Lys 297, 311, 348, and 362 Arg, which serves as a recognition signal for NDP52-dependent autophagic degradation. Specifically, RNF34 initiates the K63- to K27-linked ubiquitination transition on MAVS primarily at Lys 311, which facilitates the autophagic degradation of MAVS upon RIG-I stimulation. Notably, RNF34 is required for the clearance of damaged mitochondria upon viral infection. Thus, we elucidated the mechanism by which RNF34-mediated autophagic degradation of MAVS regulates the innate immune response, mitochondrial homeostasis, and infection.

Clinical characteristics of non-alcoholic fatty liver disease in Chinese adult hypopituitary patients.

BACKGROUND: Patients with hypothalamic-pituitary disease have the feature of central obesity, insulin resistance, and dyslipidemia, and there is increased prevalence of liver dysfunction consistent with non-alcoholic fatty liver disease (NAFLD) in this population. The causes of hypopituitarism in the reported studies varied and combined pituitary hormone deficiency including central diabetes insipidus is much common in this population. This retrospective cross-sectional study was performed to analyze the clinical characteristics and related factors with NAFLD and cirrhosis in Chinese adult hypopituitary/panhypopituitary patients. AIM: To analyze the clinical characteristics of and related risk factors for NAFLD in Chinese adult hypopituitary patients. METHODS: Adult Chinese patients with hypopituitarism and/or panhypopituitarism were enrolled at the Pituitary Center of Peking Union Medical College Hospital between August 2012 and April 2018. According to abdominal ultrasonography, these patients were divided into an NAFLD (-) group and an NAFLD (+) group, and the latter was further divided into an NAFLD group and a cirrhotic group. The data, such as patient characteristics, diagnosis, and treatment, were extracted from medical records, and statistical analysis was performed. RESULTS: A total of 36 male and 14 female adult Chinese patients with hypopituitarism were included in this retrospective study; 43 (87.0%) of these patients exhibited growth hormone (GH) deficiency, and 39 (78.3%) had diabetes insipidus. A total of 27 (54.0%) patients were diagnosed with NAFLD, while seven patients were cirrhotic. No significant differences were noted in serum GH or insulin-like growth factor 1 among patients with cirrhosis, subjects with NAFLD, and those without NAFLD. However, plasma osmolality and serum sodium concentration of the cirrhotic patients were 314.9 mOsm/kgH2O and 151.0 mmol/L, respectively, which were significantly higher than those of the NAFLD patients (P = 0.036 and 0.042, respectively). Overweight/obesity and insulin resistance were common metabolic disorders in this population. The body mass index (BMI) and homeostasis model assessment of insulin resistance parameters of the cirrhotic patients were 27.7 kg/m2 and 9.57, respectively, which were significantly higher than those of the patients without NAFLD (P = 0.011 and 0.044, respectively). A correlation analysis was performed, and fasting insulin concentration was positively associated with plasma osmolality in patients with NAFLD, after adjusting for gender, age, and BMI (r = 0.540, P = 0.046), but no correlation was noted in patients without NAFLD. CONCLUSION: NAFLD is common in patients with hypopituitarism. Plasma osmolality and serum sodium levels of hypopituitary patients with cirrhosis are higher than those of subjects with NAFLD, and fasting insulin concentration is positively associated with plasma osmolality in patients with NAFLD, which suggests that hyperosmolality might be a contributor to the worsening of NAFLD in hypopituitary patients.

Role of deubiquitinases in DNA damage response.

DNA damage response (DDR) serves as an integrated cellular network to detect cellular stress and react by activating pathways responsible for halting cell cycle progression, stimulating DNA damage repair, and initiating apoptosis. Efficient DDR protects cells from genomic instability while defective DDR can allow DNA lesions to go unrepaired, causing permanent mutations that will affect future generations of cells and possibly cause disease conditions such as cancer. Therefore, DDR mechanisms must be tightly regulated in order to ensure organismal health and viability. One major way of DDR regulation is ubiquitination, which has been long known to control DDR protein localization, activity, and stability. The reversal of this process, deubiquitination, has more recently come to the forefront of DDR research as an important new angle in ubiquitin-mediated regulation of DDR. As such, deubiquitinases have emerged as key factors in DDR. Importantly, deubiquitinases are attractive small-molecule drug targets due to their well-defined catalytic residues that provide a promising avenue for developing new cancer therapeutics. This review focuses on the emerging roles of deubiquitinases in various DNA repair pathways.

A generic strategy based on gas phase decomposition of protonated and ammoninted precursors producing predictable MRM-MS ion pairs and collision energies for direct analysis of plant triterpene glycosides.

Optimization of multiple reaction monitoring mass spectrometry (MRM-MS) parameters of triterpene glycosides (TGs) using traditional infusion methods remains to be labor-intensive. However, it was found that mild gas phase decompositions of protonated and ammoninted precursors (DPAP) of TGs could produce a series of abundant dehydrated product ions of aglycones ([A+H-nH2O]+ (n = 0, 1, 2, 3…)) with high efficiency and stability. Based on these considerations and findings, an innovative ESI+-MRM-DPAP-MS strategy was devised on a QTRAP 4000 instrument allowing for rapid the qualitative and quantitative analysis of plant TGs. A detailed study of 85 model compounds from 20 herbal medicines was implemented for validation and evaluation of the ESI+-MRM-DPAP-MS strategy proposed. The central composition design confirmed that collision energy (CE) played more significant roles than declustering potentials (DP) for the formation of these Q1/Q3 ion pairs based on MRM-DPAP-MS. It is also noted that Q1 and Mw were the most important factors for the prediction of CE values by a partial least square regression model. Here, we demonstrated this generic workflow and its merits in: (1) early prediction and selection of MRM ion pairs, no matter which type of TGs, employing a new-found Q1/Q3 calculation formula (Q1=[M+H/NH4]+ and Q3= [A+H-nH2O]+ (n = 0, 1, 2, 3…)); (2) direct determination of practicable CE values using TGs-specific CE-estimating linear equations; (3) appearances of excellent sensitivity, stability and repeatability through real application in Aralia elata, Panax notoginseng and Caulophyllum robustum; (4) seamless application of optimal CE parameters in other triple quadrupole MS instruments such as Thermo TSQ Quantum Ultra. The ESI+-MRM- DPAP-MS may service as an effective and feasible approach for analytical characterization of biological TGs from herbal medicines.