The only known pathway for biosynthesis of the polyamine norspermidine starts from aspartate β-semialdehyde to form the diamine 1,3-diaminopropane, which is then converted to norspermidine via a carboxynorspermidine intermediate. This pathway is found primarily in the Vibrionales order of the γ-Proteobacteria. However, norspermidine is also found in other species of bacteria and archaea, and in diverse single-celled eukaryotes, chlorophyte algae and plants that do not encode the known norspermidine biosynthetic pathway.
View Article and Find Full Text PDFSpermine synthase is an aminopropyltransferase that adds an aminopropyl group to the essential polyamine spermidine to form tetraamine spermine, needed for normal human neural development, plant salt and drought resistance, and yeast CoA biosynthesis. We functionally identify for the first time bacterial spermine synthases, derived from phyla Bacillota, Rhodothermota, Thermodesulfobacteriota, Nitrospirota, Deinococcota, and Pseudomonadota. We also identify bacterial aminopropyltransferases that synthesize the spermine same mass isomer thermospermine, from phyla Cyanobacteriota, Thermodesulfobacteriota, Nitrospirota, Dictyoglomota, Armatimonadota, and Pseudomonadota, including the human opportunistic pathogen Pseudomonas aeruginosa.
View Article and Find Full Text PDFBackground: Secretory carcinoma (SC) is a newly described entity which has been often misdiagnosed earlier as acinic cell carcinoma on cytology. Diagnosing SC was initially based upon identifying the : fusion gene with the help of fluorescence hybridization (FISH). Lately, with more knowledge of the reliable histomorphology, cytology, and immunohistochemistry features, definitive diagnosis can be confidently made without the help of FISH in almost every case.
View Article and Find Full Text PDFBackground: Leukemic cells express a characteristic set of "cluster of differentiation" (CD) markers, which forms the basis of the current WHO classification. Leukemia-associated aberrant immunophenotype (LAIP) refers to expression of unusual CD markers by leukemic cells, which are not normally expressed by their respective lineage. The incidence of LAIP varies considerably, and its clinical implications, prognostic relevance, and sensitivity to therapy are still debatable.
View Article and Find Full Text PDFS-adenosylmethionine decarboxylase (AdoMetDC/SpeD) is a key polyamine biosynthetic enzyme required for conversion of putrescine to spermidine. Autocatalytic self-processing of the AdoMetDC/SpeD proenzyme generates a pyruvoyl cofactor from an internal serine. Recently, we discovered that diverse bacteriophages encode AdoMetDC/SpeD homologs that lack AdoMetDC activity and instead decarboxylate L-ornithine or L-arginine.
View Article and Find Full Text PDFBackground: Granulomatous cheilitis (GC) is a rare entity of unknown etiology. It is a chronic inflammatory disorder with a predilection for young females. It is characterized by asymptomatic unrelenting swelling of lips.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2023
Viruses produce more viruses by manipulating the metabolic and replication systems of their host cells. Many have acquired metabolic genes from ancestral hosts and use the encoded enzymes to subvert host metabolism. The polyamine spermidine is required for bacteriophage and eukaryotic virus replication, and herein, we have identified and functionally characterized diverse phage- and virus-encoded polyamine metabolic enzymes and pathways.
View Article and Find Full Text PDFObjectives: In breast carcinomas, histomorphological features like low-grade and lobular differentiation are associated with estrogen receptor (ER) and progesterone receptor (PR) expression. Apocrine carcinoma is associated with human epidermal growth factor receptor 2 (HER2) positivity. Studies have not emphasized the association between other histological features like tubule formation, Indian file pattern and apocrine change (which may be found in all grades of tumors or as a part of a mixed pattern of no special type) and immunohistochemistry (IHC).
View Article and Find Full Text PDFCancer immunotherapy targeting the programmed cell death ligand 1 (PD-L1) and programmed cell death-1 (PD-1) axis has revolutionized cancer therapy. PD-L1 also serves as a predictive marker for such therapy. To assess the potential of such therapy in any cancer, the positivity of PD-1 and PD-L1 in such cancers needs to be assessed.
View Article and Find Full Text PDFFrom the aspect of exploring the alternative lightweight composite material for the aerospace launch vehicle external fuel tank structural components, the current research work studies three different grades of Aluminium alloy reinforced with varying graphene weight percentages that are processed through powder metallurgy (P/M) route. The prepared green compacts composite ingots are subjected to microwave processing (Sintering), hot extruded, and solution treated (T6). The developed Nano-graphene reinforced composite is studied further for the strength-microstructural integrity.
View Article and Find Full Text PDFUrothelial carcinomas are the most common types of bladder tumors that have recently shown a changing trend in treatment protocols with the introduction and approval of immune checkpoint inhibitors. The most important immune checkpoint lies with the PD-1-PD-L1 axis. Although multiple drugs have been approved, there is uncertainty about patient selection criteria and diagnostic assays.
View Article and Find Full Text PDFMucinous ovarian carcinoma is a less-prevalent subtype of epithelial tumors. We present a case of giant mucinous ovarian carcinoma weighing 41.1 kg in a 24-year-old Indian girl.
View Article and Find Full Text PDFAims: This case-control study was conducted to identify maternal and placental risk factors of small-for-gestational-age (SGA) and fetal malnutrition.
Methods: Cases comprised 104 consecutively delivered SGA neonates (determined as per INTERGROWTH- 21st standard). An equal number of next-born gestation and gender-matched appropriatefor- gestational age (AGA) neonates served as controls.
Aim To study the prevalence of programmed death-1 receptor (PD-1) and programmed death-ligand 1 (PD-L1) positive cases in non-small-cell lung carcinoma (NSCLC) and their association with other clinicopathological parameters in a tertiary care setting in North India. Material and methods One hundred histologically proven NSCLC cases having sufficient tumor material from July 2016 to July 2018 were examined, and the prevalence of PD-1 and PD-L1 positivity in NSCLC was studied. In addition, H&E-stained sections were reviewed, and 100 consecutive cases meeting study criteria were identified as study cases.
View Article and Find Full Text PDFBackground: The exact etiology of adolescent idiopathic scoliosis (AIS) is unknown, but recently, vitamin D has been suggested to be of importance in the pathophysiology of AIS. This article sought to (1) highlight the prevalence of vitamin D deficiency in patients undergoing corrective surgery for AIS within the United Kingdom and (2) evaluate the correlation and clinical relevance of preoperative back pain with vitamin D deficiency.
Methods: Data were collected on 201 consecutive patients undergoing corrective surgery for AIS.
Introduction: Focused studies in different geographic regions would delineate the underlying biological differences and molecular alterations in non-small cell lung cancer (NSCLC) worldwide. Previous studies in literature have documented limited characterization by studying a minimal number of biological markers. This study was done to evaluate expression of multiple immunomarkers including diagnostic, prognostic, and predictive markers in NSCLC for its characterization.
View Article and Find Full Text PDFVindu et al. (2021) identify the yeast high-affinity spermidine transporter, elucidate the mRNA uORF/eIF5a-based translational mechanism by which spermidine levels are sensed, and demonstrate that excess spermidine competitively inhibits eIF5a function, resulting in decreased spermidine uptake.
View Article and Find Full Text PDFPolyamines are fundamental molecules of life, and their deep evolutionary history is reflected in extensive biosynthetic diversification. The polyamines putrescine, agmatine, and cadaverine are produced by pyridoxal 5'-phosphate-dependent L-ornithine, L-arginine, and L-lysine decarboxylases (ODC, ADC, LDC), respectively, from both the alanine racemase (AR) and aspartate aminotransferase (AAT) folds. Two homologous forms of AAT-fold decarboxylase are present in bacteria: an ancestral form and a derived, acid-inducible extended form containing an N-terminal fusion to the receiver-like domain of a bacterial response regulator.
View Article and Find Full Text PDFIntroduction: The aim of this case report is to present an option of reconstruction in tumors involving the posterior wall and column of the acetabulum with sparing of the anterior column and the weight-bearing dome.
Case Report: We are reporting a case of a 25-year-old female with histopathologically proven synovial sarcoma involving the left inferior pubic ramus, ischium, and posterior wall of the acetabulum, along with a large soft-tissue extension in the posterior and medial thigh. Wide local excision involving partial acetabular resection and reconstruction using a femoral head allograft was carried out.
Background: Fine-needle aspiration biopsy (FNAB) in breast lesions offers accurate results in differentiating benign and malignant lesions. However, its role is unclear when core-needle biopsy (CNB) is available, the latter providing additional information regarding tumor grade, invasion, and hormone receptor status in malignant lesions. In benign breast lesions, especially in BIRADS category 4a and 4b, FNAB, and CNB provide similar pathological information, whereby FNAB may serve as a more rapid and cost-effective investigation.
View Article and Find Full Text PDFBackground: First metatarsophalangeal joint fusion is a commonly used procedure for treating many pathologic disorders of the first ray. Historically, hallux valgus deformity with severely increased intermetatarsal angle or metatarsus primus adductus indicated need for a proximal metatarsal procedure. However, the effectiveness and reliability of first metatarsophalangeal joint arthrodesis in reducing the intermetatarsal angle has been increasingly described in the literature.
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