Human Plasma Very Low-Density Lipoproteins Are Stabilized by Electrostatic Interactions and Destabilized by Acidic pH

Very low-density lipoproteins (VLDL) are precursors of low-density lipoproteins (LDL, or “bad cholesterol”). Factors affecting structural integrity of VLDL are important for their metabolism. To assess the role of electrostatic interactions in VLDL stability, we determined how solvent ionic conditions affect the heat-induced VLDL remodeling. This remodeling involves VLDL fusion, rupture, and fission of apolipoprotein E-containing high-density lipoprotein-(HDL-) like particles similar to those formed during VLDL-to-LDL maturation. Circular dichroism and turbidity show that increasing sodium salt concentration in millimolar range reduces VLDL stability and its enthalpic component. Consequently, favorable electrostatic interactions stabilize VLDL. Reduction in pH from 7.4 to 6.0 reduces VLDL stability, with further destabilization detected at pH < 6, which probably results from titration of the N-terminal α-amino groups and free fatty acids. This destabilization is expected to facilitate endosomal degradation of VLDL, promote their coalescence into lipid droplets in atherosclerotic plaques, and affect their potential use as drug carriers

Non-enzymatic interactions of glyoxylate with lysine, arginine, and glucosamine: a study of advanced non-enzymatic glycation like compounds

Glyoxylate is a 2 carbon aldo acid that is formed in hepatic tissue from glycolate. Once formed, the molecule can be converted to glycine by alanine-glyoxylate aminotransferase (AGAT). In defects of AGAT, glyoxylate is transformed to oxalate, resulting in high levels of oxalate in the body. The objective of this study was 2-fold. First, it was to determine, if akin to D-glucose, D-fructose or DL-glyceraldehyde, glyoxylate was susceptible to non-enzymatic attack by amino containing molecules such as lysine, arginine or glucosamine. Second, if by virtue of its molecular structure and size, glyoxylate was as reactive a reagent in non-enzymatic reactions as DL-glyceraldehyde; i.e., a glycose that we previously demonstrated to be a more effective glycating agent than D-glucose or D-fructose. Using capillary electrophoresis (CE), high performance liquid chromatography and UV and fluorescence spectroscopy, glyoxylate was found to be a highly reactive precursor of advanced glycation like end products (AGLEs) and a more effective promoter of non-enzymatic end products than D-glucose, D-fructose or DL-glyceraldehyde

Primary Hydatid Cysts in Rare Sites: A Series of Four Cases

Hydatid disease is caused by the larval stage of the tapeworm Echinococcus granulosus. The definitive hosts include dogs and canines. Humans are accidental hosts and do not play a role in the biological cycle of the worm. The mode of infection is through ingesting food contaminated with dog feces containing gravid proglottids and free eggs, which hatch in the intestine and form larvae. The larvae then penetrate the intestinal wall, enter the bloodstream, and typically settle in the liver followed by the lungs. However, in rare instances, hydatid cysts can occur in various unusual sites throughout the body and even in a disseminated manner, leading to atypical clinical presentations and diagnostic challenges. Hereby, authors report a series of four cases (three males and one female) of hydatid cysts occurring at unusual sites, mainly the brain, kidney, spleen, and lung. The common age group among the observed cases was the second to fourth decade, showing a male predominance. In cases of splenic and renal hydatid cysts, patients presented with intermittent dull aching pain over the left and right flanks, respectively. In both cases, ultrasonography revealed the presence of multiple cysts in the spleen and kidney. In the case of cerebral hydatid cysts, the patient provided a history of short-term memory loss along with a few non specific symptoms, and Magnetic Resonance Imaging (MRI) revealed a hyperintense cystic lesion. In pulmonary hydatid cysts, the patient presented with symptoms of cough, dyspnoea, chest pain, and expectoration. X-ray examination supported the presence of the cyst. Surgery, preferably radical cystectomy, is considered for treatment, and the diagnosis is always confirmed by histopathology

Expression of GATA3, p63, E-cadherin and Her2Neu Immunohistochemical Stains in Urothelial Carcinoma and their Relationship with Histological Grading and Prognosis- A Cross-sectional Study

Introduction: Urinary bladder cancer is the 10th most common cancer worldwide. Cystoscopy and biopsy/Transurethral Resection of Bladder Tumour (TURBT) are the best techniques for diagnosing and staging urinary bladder cancers. Urothelial Carcinomas (UC), particularly in transurethral resection biopsies, can pose diagnostic difficulties due to limited material. Immunohistochemistry (IHC) plays a valuable role in these settings, and many immunostains are being utilised for diagnostic evaluation. However, the relationship of these immunomarkers with histological grade and their prognostic utility has not been adequately explored. Aim: To analyse expression of Her2Neu, E-cadherin, p63, and GATA3 in UC and its relation with histological grading and prognosis. Materials and Methods: This was an observational cross-sectional study conducted in the Pathology Department of IPGMER and SSKM Hospital, Kolkata, West Bengal, India over two years (November 2020-October 2022). Samples of 100 bladder carcinoma patients with predominant TURBT specimens were included in the study. The histopathological reports and tumour grading were done according to the World Health Organisation (WHO) classification of urinary bladder tumours. The Formalin Fixed Paraffin-embedded (FFPE) sections of the tumour blocks were subjected to IHC staining, and the results were interpreted accordingly. Statistical analysis was performed with the help of the Statistical Package for Social Sciences (SPSS), IBM (version 25.0). Unpaired t-test and Z-test (Standard Normal Deviate) were used to test the significant difference between two proportions. Results: The mean age of the study population was 59.69±14.53 years, and there was a male preponderance (male: female=3.54:1). Histopathological examination revealed 55% to be of low-grade morphology. Overall, 53% of cases were in T1 stage, and the rest were in T2 stage. On IHC analysis, E-cadherin showed a statistically significant decrease in intensity with increasing grade (p-value <0.001) and T stage of UC (p-value <0.001), but there was no statistically significant relationship between Her2Neu expression and tumour grade/stage (p-value 0.5764 and 0.5663, respectively). A statistically significant relationship was observed between GATA3 and p63 scores with the grade and T stage of the tumour, i.e., GATA3 positivity increased with increasing grade and T stage of the tumour (p-value <0.001 in both), and there was a loss of p63 with advancing grade and stage of the tumour (p-value <0.001 in both). Conclusion: GATA3, p63, and E-cadherin can be used as prognostic markers in UCs. No significant relationship was found between Her2Neu expression and tumour grade in UC

Effects of acyl chain length, unsaturation, and pH on thermal stability of model discoidal HDLs*s⃞

HDLs prevent atherosclerosis by removing excess cell cholesterol. Lipid composition affects HDL functions in cholesterol removal, yet its effects on the disk stability remain unclear. We hypothesize that reduced length or increased cis-unsaturation of phosphatidylcholine acyl chains destabilize discoidal HDL and promote protein dissociation and lipoprotein fusion. To test this hypothesis, we determined thermal stability of binary complexes reconstituted from apoC-I and diacyl PCs containing 12–18 carbons with 0–2 cis-double bonds. Kinetic analysis using circular dichroism shows that, for fully saturated PCs, chain length increase by two carbons stabilizes lipoprotein by δΔG* (37°C) ≅ 1.4 kcal/mol, suggesting that hydrophobic interactions dominate the disk stability; distinct effects of pH and salt indicate contribution of electrostatic interactions. Similarly, apoA-I-containing disks show increased stability with increasing chain length. Acyl chain unsaturation reduces disk stability. In summary, stability of discoidal HDL correlates directly with fatty acyl chain length and saturation: the longer and more fully saturated are the chains, the more extensive are the stabilizing lipid-protein and lipid-lipid interactions and the higher is the free energy barrier for protein dissociation and lipoprotein fusion. This sheds new light on the existing data of cholesterol efflux to discoidal HDL and suggests that moderate lipoprotein destabilization facilitates cholesterol insertion

Therapy with radio-attenuated vaccine in experimental murine visceral leishmaniasis showed enhanced T cell and inducible nitric oxide synthase levels, suppressed tumor growth factor-beta production with higher expression of some signaling molecules

Background: Visceral leishmaniasis (VL) or Kala-Azar (KA) is one of the most deadly formsof disease among all neglected tropical diseases. There are no satisfactory drugs or vac-cine candidates available for this dreaded disease. Our previous studies showed promisingtherapeutic and prophylactic efficacy of the live, radio-attenuated parasites through intra-muscular (I.M.) and intraperitoneal (I.P.) route in BALB/c mice model.Methods: The T-cell proliferation level, the mRNA expression level of inducible nitric oxidesynthase (iNOS) and tumor growth factor-beta (TGF-�) genes and finally the phosphorylationlevels of phosphoinositide dependent kinase 1 (PDK1), phosphoinositide 3 kinase (PI3K) andp38 mitogen activated protein kinase (p38MAPK) molecules were checked in BALB/c micemodel immunized with radio-attenuated Leishmania donovani parasites through I.M. route.Results: Higher T-cell proliferation, increased iNOS level, and suppressed TGF-� level werefound in treated infected animal groups (100 and 150 Gy) in relation to untreated infectedanimals. Likewise, phosphorylation levels of PDK1, PI3K and p38MAPK of these two groupswere increased when compared to untreated infected controls.Conclusion: The clearance of the parasites from treated infected groups of animals maybe mediated by the restoration of T-cell due to therapy with radio-attenuated L. donovaniparasites. The killing of parasites was mediated by increase in nitric oxide release throughPDK1, PI3K and p38MAPK signaling pathways. A lower TGF-� expression has augmentedthe restored Th1 ambience in the 100 and 150 Gy treated animal groups proving further theefficacy of the candidate vaccin