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Sheth ABN, Patra A, Mahajan D. Anatomical variations and developmental insights of tendons in the first extensor compartment of the hand: Cadaveric study with surgical implications. LA CLINICA TERAPEUTICA 2024; 175:26-33. [PMID: 38358474 DOI: 10.7417/ct.2024.5030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
Background Anatomical variations in first extensor compartment play a role in the development of de Quervain's disease. This study delves into the detailed examination of these anatomical variations. Methods 50 upper limbs (28 male and 22 female) from 25 for-malin-embalmed adult human cadavers were dissected to investigate variations in tendons of first extensor compartment. Results Accessory tendons to main tendon of abductor pollicis longus (APL) were reported in 49 (98%) cases, with 34% having two accessory tendons, 52% having three, and 12% having four. Terminal ends of these accessory tendons were generally consistent, except in one case where it split into two tendinous bands at insertion site, which was most commonly at base of first metacarpal. Extensor pollicis brevis (EPB) was found as a single tendon in 48 cases, with one case each of duplication and absence. In 19 cases (38%), muscle belly of EPB was fused with that of APL to some extent and it typically inserted at base of the proximal phalanx of the thumb. Average length of muscle belly, tendon, and muscle tendon ratio (MTR) of APL was 15.99±0.62 cm, 5.91±0.76 cm and 2.71 and of EPB was 6.39±0.29 cm, 9.15±0.74 cm and 0.70 respectively. Conclusion APL variations range from accessory tendons, splitting of tendons to various insertion points. Additionally, length and insertions points of these accessory tendons are key factors in deciding their usability as graft sources for tendon reconstruction and in surgical treatments of conditions like de Quervain's tenosynovitis.
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Naito T, Yang H, Koh DHZ, Mahajan D, Lu L, Saheki Y. Regulation of cellular cholesterol distribution via non-vesicular lipid transport at ER-Golgi contact sites. Nat Commun 2023; 14:5867. [PMID: 37735529 PMCID: PMC10514280 DOI: 10.1038/s41467-023-41213-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 08/28/2023] [Indexed: 09/23/2023] Open
Abstract
Abnormal distribution of cellular cholesterol is associated with numerous diseases, including cardiovascular and neurodegenerative diseases. Regulated transport of cholesterol is critical for maintaining its proper distribution in the cell, yet the underlying mechanisms remain unclear. Here, we show that lipid transfer proteins, namely ORP9, OSBP, and GRAMD1s/Asters (GRAMD1a/GRAMD1b/GRAMD1c), control non-vesicular cholesterol transport at points of contact between the ER and the trans-Golgi network (TGN), thereby maintaining cellular cholesterol distribution. ORP9 localizes to the TGN via interaction between its tandem α-helices and ORP10/ORP11. ORP9 extracts PI4P from the TGN to prevent its overaccumulation and suppresses OSBP-mediated PI4P-driven cholesterol transport to the Golgi. By contrast, GRAMD1s transport excess cholesterol from the Golgi to the ER, thereby preventing its build-up. Cells lacking ORP9 exhibit accumulation of cholesterol at the Golgi, which is further enhanced by additional depletion of GRAMD1s with major accumulation in the plasma membrane. This is accompanied by chronic activation of the SREBP-2 signalling pathway. Our findings reveal the importance of regulated lipid transport at ER-Golgi contacts for maintaining cellular cholesterol distribution and homeostasis.
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Mahajan D, Tie HC, Lu L. Visualizing the Cisternal Organization of Golgi Ministacks in HeLa Cells by Side-averaging. Bio Protoc 2023; 13:e4658. [PMID: 37113336 PMCID: PMC10127052 DOI: 10.21769/bioprotoc.4658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/10/2023] [Accepted: 03/02/2023] [Indexed: 04/29/2023] Open
Abstract
The mammalian Golgi complex consists of laterally connected Golgi stacks, each comprising close-packed and flattened membrane sacks called cisternae. However, the convoluted spatial organization of Golgi stacks and limited resolution of light microscopy prevent us from resolving the cisternal organization of the Golgi. Here, we describe our recently developed side-averaging approach coupled with Airyscan microscopy to visualize the cisternal organization of nocodazole-induced Golgi ministacks. First, the nocodazole treatment greatly simplifies the organization of Golgi stacks by spatially separating the crowded and amorphous Golgi complex into individual disk-shaped ministacks. The treatment also makes it possible to identify en face and side-views of Golgi ministacks. Next, after manually selecting the side-view Golgi ministack images, they are transformed and aligned. Finally, the resulting images are averaged to enhance the common structural features and suppress the morphological variations among individual Golgi ministacks. This protocol describes how to image and analyze the intra-Golgi localization of giantin, GalT-mCherry, GM130, and GFP-OSBP in HeLa cells by side-averaging. Graphical abstract.
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Mahajan D, Madugula V, Lu L. Rab8 and TNPO1 are ciliary transport adaptors for GTPase Arl13b by interacting with its RVEP motif-containing ciliary targeting sequence. J Biol Chem 2023; 299:104604. [PMID: 36907439 PMCID: PMC10124946 DOI: 10.1016/j.jbc.2023.104604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 03/04/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
Arl13b, an ARF/Arl-family GTPase, is highly enriched in the cilium. Recent studies have established Arl13b as one of the most crucial regulators for ciliary organization, trafficking, and signaling. The ciliary localization of Arl13b is known to require the RVEP motif. However, its cognitive ciliary transport adaptor has been elusive. Here, by imaging the ciliary localization of truncation and point mutations, we defined the ciliary targeting sequence (CTS) of Arl13b as a C-terminal stretch of 17 amino acids containing the RVEP motif. We found Rab8-GDP, but not Rab8-GTP, and TNPO1 simultaneously and directly bind to the CTS of Arl13b in pull-down assays using cell lysates or purified recombinant proteins. Furthermore, Rab8-GDP substantially enhances the interaction between TNPO1 and CTS. Additionally, we determined that the RVEP motif is an essential element as its mutation abolishes the interaction of the CTS with Rab8-GDP and TNPO1 in pull-down and TurboID-based proximity ligation assays. Finally, knockdown of endogenous Rab8 or TNPO1 decreases the ciliary localization of endogenous Arl13b. Therefore, our results suggest Rab8 and TNPO1 might function together as a ciliary transport adaptor for Arl13b by interacting with its RVEP-containing CTS.
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Tie HC, Mahajan D, Lu L. Visualizing intra-Golgi localization and transport by side-averaging Golgi ministacks. J Biophys Biochem Cytol 2022; 221:213180. [PMID: 35467701 DOI: 10.1083/jcb.202109114] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/03/2021] [Accepted: 04/05/2022] [Indexed: 01/09/2023] Open
Abstract
The mammalian Golgi comprises tightly adjacent and flattened membrane sacs called cisternae. We still do not understand the molecular organization of the Golgi and intra-Golgi transport of cargos. One of the most significant challenges to studying the Golgi is resolving Golgi proteins at the cisternal level under light microscopy. We have developed a side-averaging approach to visualize the cisternal organization and intra-Golgi transport in nocodazole-induced Golgi ministacks. Side-view images of ministacks acquired from Airyscan microscopy are transformed and aligned before intensity normalization and averaging. From side-average images of >30 Golgi proteins, we uncovered the organization of the pre-Golgi, cis, medial, trans, and trans-Golgi network membrane with an unprecedented spatial resolution. We observed the progressive transition of a synchronized cargo wave from the cis to the trans-side of the Golgi. Our data support our previous finding, in which constitutive cargos exit at the trans-Golgi while the secretory targeting to the trans-Golgi network is signal dependent.
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Sun X, Mahajan D, Chen B, Song Z, Lu L. A quantitative study of the Golgi retention of glycosyltransferases. J Cell Sci 2021; 134:272560. [PMID: 34533190 DOI: 10.1242/jcs.258564] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 09/09/2021] [Indexed: 11/20/2022] Open
Abstract
How Golgi glycosyltransferases and glycosidases (hereafter glycosyltransferases) localize to the Golgi is still unclear. Here, we first investigated the post-Golgi trafficking of glycosyltransferases. We found that glycosyltransferases can escape the Golgi to the plasma membrane, where they are subsequently endocytosed to the endolysosome. Post-Golgi glycosyltransferases are probably degraded by ectodomain shedding. We discovered that most glycosyltransferases are not retrieved from post-Golgi sites, indicating that retention rather than retrieval is the primary mechanism for their Golgi localization. We therefore used the Golgi residence time to study Golgi retention of glycosyltransferases quantitatively and systematically. Quantitative analysis of chimeras of ST6GAL1 and either transferrin receptor or tumor necrosis factor α revealed the contributions of three regions of ST6GAL1, namely the N-terminal cytosolic tail, the transmembrane domain and the ectodomain, to Golgi retention. We found that each of the three regions is sufficient for Golgi retention in an additive manner. N-terminal cytosolic tail length negatively affects the Golgi retention of ST6GAL1, similar to effects observed for the transmembrane domain. Therefore, the long N-terminal cytosolic tail and transmembrane domain could act as Golgi export signals for transmembrane secretory cargos. This article has an associated First Person interview with the first author of the paper.
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Zhang H, Ba S, Mahajan D, Lee JY, Ye R, Shao F, Lu L, Li T. Versatile Types of DNA-Based Nanobiosensors for Specific Detection of Cancer Biomarker FEN1 in Living Cells and Cell-Free Systems. NANO LETTERS 2018; 18:7383-7388. [PMID: 30336066 DOI: 10.1021/acs.nanolett.8b03724] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Flap structure-specific endonuclease 1 (FEN1) is overexpressed in various types of human cancer cells and has been recognized as a promising biomarker for cancer diagnosis in the recent years. In order to specifically detect the abundance and activity of this cancer-overexpressed enzyme, different types of DNA-based nanodevices were created during our investigations. It is shown in our studies that these newly designed biosensors are highly sensitive and specific for FEN1 in living cells as well as in cell-free systems. It is expected that these nanoprobes could be useful for monitoring FEN1 activity in human cancer cells, and also for cell-based screening of FEN1 inhibitors as new anticancer drugs.
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Devanapalli B, Lee S, Mahajan D, Bermingham M. Lipoprotein (a) in an immigrant Indian population sample in Australia. Br J Biomed Sci 2018. [DOI: 10.1080/09674845.2002.11978033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Mahajan D, Votruba M. Can the retina be used to diagnose and plot the progression of Alzheimer's disease? Acta Ophthalmol 2017. [DOI: 10.1111/j.1755-3768.2017.0t061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Mahajan D, Votruba M. A novel NR2E3 gene mutation in autosomal recessive retinitis pigmentosa with cystic maculopathy. Acta Ophthalmol 2017. [DOI: 10.1111/j.1755-3768.2017.02682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Tie HC, Mahajan D, Chen B, Cheng L, VanDongen AMJ, Lu L. A novel imaging method for quantitative Golgi localization reveals differential intra-Golgi trafficking of secretory cargoes. Mol Biol Cell 2016; 27:848-61. [PMID: 26764092 PMCID: PMC4803310 DOI: 10.1091/mbc.e15-09-0664] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 01/07/2016] [Indexed: 12/02/2022] Open
Abstract
A novel imaging-based method is introduced to quantitatively localize Golgi proteins at nanometer resolution. The method reveals different intra-Golgi trafficking of secretory cargoes. Cellular functions of the Golgi are determined by the unique distribution of its resident proteins. Currently, electron microscopy is required for the localization of a Golgi protein at the sub-Golgi level. We developed a quantitative sub-Golgi localization method based on centers of fluorescence masses of nocodazole-induced Golgi ministacks under conventional optical microscopy. Our method is rapid, convenient, and quantitative, and it yields a practical localization resolution of ∼30 nm. The method was validated by the previous electron microscopy data. We quantitatively studied the intra-Golgi trafficking of synchronized secretory membrane cargoes and directly demonstrated the cisternal progression of cargoes from the cis- to the trans-Golgi. Our data suggest that the constitutive efflux of secretory cargoes could be restricted at the Golgi stack, and the entry of the trans-Golgi network in secretory pathway could be signal dependent.
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Dharmarajan T, Dharmarajan T, Mahajan D, Zambrano A, Fischer R, Agarwal B, Lebelt A, Patel M, Vance J, Norkus E. Sliding-Scale Insulin (SSI) vs. Basal/Basal-Bolus Insulin (B-BI) Therapy in Long-Term Care (LTC): Results from a 21-Day Intervention Trial. J Am Med Dir Assoc 2015. [DOI: 10.1016/j.jamda.2015.01.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Agnihotri G, Mahajan D. Cor triloculare biatriatum--A case report. NEPAL MEDICAL COLLEGE JOURNAL : NMCJ 2014; 16:198-200. [PMID: 26930746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cor triloculare biatriatum or double inlet single ventricle is a congenital heart defect in which both atria are connected to a common or dominant ventricle. The present report presents an index case and describes the embryological basis and clinical aspects of this extremely rare anomaly. A three months old infant presented with extreme respiratory distress without cyanosis and repeated chest infections. The patient was diagnosed to be a case of single ventricle with both atria opening in the common ventricular chamber. The common ventricular chamber (single ventricle) was connected to a rudimentary outflow tract. The great arteries were in a position of d-transposition of great arteries. However, there was no pulmonary or aortic stenosis. A clear concept and awareness regarding this condition and its clinical manifestations is bound to facilitate timely intervention with improved success rates.
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Mahajan D, Perschbacher D, Jones P, Reddy S, Sharma A. Different manifestations of right ventricular icd advisory leads using impedance and noise. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht308.p1393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Agrawal S, Jain A, Mahajan D, Raghunandan C. Correlation of bone mineral density with biochemical markers in post menopausal women. Indian J Clin Biochem 2009; 24:262-5. [PMID: 23105846 DOI: 10.1007/s12291-009-0049-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To evaluate the magnitude of bone loss in postmenopausal women and to study the effect of a selective estrogen Receptor Modulator, raloxifene, on bone loss by quantitative ultrasound of calcaneus and serum bone specific alkaline phosphatase (BAP). Postmenopausal women with ostesopenia/osteoporosis were assigned randomly to receive placebo (n=30) or raloxifene (60mg/d, n=30) with calcium (500mg/day) and vitamin D (250 IU/day). The bone mineral density (BMD) and BAP levels were measured at the beginning of therapy and six months later. They were subjected to statistical analysis (t test, p value) using SPSS statistical package. 70% of postmenopausal women suffered from osteopenia/osteoporosis. After raloxifene therapy, there was improvement in the BMD but this was not statistically significant (p>0.05). There was a fall in the value of serum BAP by 26.6% (p<0.05). Raloxifene has a favourable effect on bone turnover as evident from changes in BMD and a significant fall in serum BAP.
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Wang Y, Wang YP, Zheng G, Lee VWS, Ouyang L, Chang DHH, Mahajan D, Coombs J, Wang YM, Alexander SI, Harris DCH. Ex vivo programmed macrophages ameliorate experimental chronic inflammatory renal disease. Kidney Int 2007; 72:290-9. [PMID: 17440493 DOI: 10.1038/sj.ki.5002275] [Citation(s) in RCA: 278] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Macrophage infiltration of the kidney is a prominent feature associated with the severity of renal injury and progressive renal failure. To determine the influence of macrophages in renal disease models in the absence of endogenous T and B cells, we performed adoptive transfer of macrophages into severe combined immunodeficient (SCID) mice. In this study, macrophages were isolated from the spleens of BALB/c mice and stimulated with lipopolysaccharide to induce classically activated M1 macrophages or with interleukin-4 (IL-4) and IL-13 to induce alternatively activated M2 macrophages. These macrophages were then infused into SCID mice with adriamycin nephropathy; an in vivo model of chronic inflammatory renal disease analogous to human focal segmental glomerulosclerosis. Mice infused with M1 macrophages had a more severe histological and functional injury, whereas M2 macrophage-induced transfused mice had reduced histological and functional injury. Both M1 and M2 macrophages localized preferentially to the area of injury and maintained their phenotypes even after 4 weeks. The protective effect of M2 macrophages was associated with reduced accumulation and possibly downregulated chemokine and inflammatory cytokine expression of the host infiltrating macrophages. Our findings demonstrate that macrophages not only act as effectors of immune injury but can be induced to provide protection against immune injury.
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Mahajan D. Atom-economical reduction of carbon monoxide to methanol catalyzed by soluble transition metal complexes at low temperatures. Top Catal 2005. [DOI: 10.1007/s11244-005-2892-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Koga T, Li C, Sun Y, Brazin A, Rafailovich MH, Sokolov JC, Douglas JF, Mahajan D. Surface modification of polymeric nanocomposite thin films using supercritical carbon dioxide. Top Catal 2005. [DOI: 10.1007/s11244-005-2907-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mahajan D, Bermingham MA. Risk factors for coronary heart disease in two similar Indian population groups, one residing in India, and the other in Sydney, Australia. Eur J Clin Nutr 2004; 58:751-60. [PMID: 15116078 DOI: 10.1038/sj.ejcn.1601873] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To identify the prevalence of coronary risk factors among South Asian Indians in Australia and India. DESIGN Cross-sectional intercountry comparison. SUBJECTS Healthy volunteers aged 23-75 y recruited from the Indian community in Sydney Australia (n=125), and their nominated relatives in India, (n=125). RESULTS The two groups were of similar background with over 90% of the group in India being siblings, parents or relatives of the group in Australia. There was no difference in the populations between India and Australia with regard to mean age (40+/-11.5 vs 39+/-10.3 y), body mass index (BMI) (25+/-3.3 vs 25+/-3.5 kg/m(2)), lipoprotein (a) (178 vs 202 mg/l), total cholesterol (5.3+/-1.3 vs 5.3+/-1.2 mmol/l) or triglyceride (1.7+/-0.8 vs 1.7+/-0.8 mmol/l). The group in India had higher insulin (median values) (139 vs 83 pmol/l, P=0.0001), waist-to-hip ratio (WHR) (0.88+/-0.08 vs 0.85+/-0.09, P=0.01), exercise time (23.7+/-32.7 vs 17.2+/-23.2 h/week, P=0.07), lower waist (83+/-10.0 vs 85+/-11.1 cm, P=0.05) and high-density lipoprotein (0.9+/-0.3 vs 1.1+/-0.6 mmol/l, P=0.02). Women in India had lower BMI (22.7+/-2.9 vs 25.3+/-4.2 kg/m(2), P<0.001), higher insulin (182 vs 90 pmol/l, P<0.001), WHR (0.86+/-0.08 vs 0.77+/-0.06, P<0.001)) and prevalence of abdominal obesity (% WHR >0.8, 73 vs 23%, P<0.001; odds of waist >90 cm=2.3, P<0.05). Men in India had the same BMI, lower waist (85.5+/-8.8 vs 92.9+/-7.2 cm, P<0.001) and WHR (0.89+/-0.09 vs 0.93+/-0.05, P<0.01) but higher insulin (137 vs 76 pmol/l). CONCLUSION The group in Australia (especially women) have a more favourable disease risk profile than those in India. The fact that the groups are of such similar background and partly related, make it unlikely that changes due to migration have a strong genetic bias. In contrast to other studies, the absence here of excessive weight gain on migration may be a key factor in disease risk prevention.
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Devanapalli B, Lee S, Mahajan D, Bermingham M. Lipoprotein (a) in an immigrant Indian population sample in Australia. Br J Biomed Sci 2002; 59:119-22. [PMID: 12113402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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Raftos D, Green P, Mahajan D, Newton R, Pearce S, Peters R, Robbins J, Nair S. Collagenous lectins in tunicates and the proteolytic activation of complement. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 484:229-36. [PMID: 11418989 DOI: 10.1007/978-1-4615-1291-2_22] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Steinbeck KS, Bermingham MA, Mahajan D, Baur LA. Low-density lipoprotein subclasses in children under 10 years of age. J Paediatr Child Health 2001; 37:550-3. [PMID: 11903833 DOI: 10.1046/j.1440-1754.2001.00753.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To examine the prevalence of small dense low density lipoprotein (LDL) in a cohort of children under 10 years of age and to investigate the relationship to other biochemical variables and to measures of fatness. A preponderance of small dense LDL (pattern B), is associated with obesity, abdominal fat accumulation, insulin resistance and risk of heart disease in adults. METHODOLOGY LDL peak particle diameter (PPD) was determined by gel electrophoresis in 53 children under 10 years of age and in 65 of their parents: apoproteins A1 and B were determined by turbidimetry. Anthropometric variables, basic lipid profiles, insulin and leptin had been determined previously. Differences between patterns A (large light particles > 25.5 nm diameter) and B were examined by t-test, Chi-square, or Mann-Whitney test. Relationships between the variables were reported as Pearson correlation coefficients. RESULTS Pattern B (PPD of < or = 25.5 nm) prevalence was 7.5% in children and 11% in parents (17% in men and 5% in women). Most of the children (86%) who had PPD < or = 26.0 nm also had parents with PPD in this range. A strong association was found between children's and mother's PPD (r=0.60, P < 0.001), but this was somewhat less with fathers (r=0.40, P=0.02). Children in the lowest tertile of PPD had a tendency towards a higher body mass index, waist, fat mass and insulin. CONCLUSIONS The prevalence of small dense LDL is lower in children under 10 years of age than in their parents; fathers had a higher prevalence of pattern B than mothers and there is some evidence of a familial effect in the inheritance of pattern B.
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Hiura Y, Mahajan D, Steinbeck K, Bermingham MA. Effect of long-term storage at -20 degrees C and -80 degrees C on apolipoprotein A1 and B in obese subjects. Br J Biomed Sci 2001; 58:30-3. [PMID: 11284221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Nair SV, Pearce S, Green PL, Mahajan D, Newton RA, Raftos DA. A collectin-like protein from tunicates. Comp Biochem Physiol B Biochem Mol Biol 2000; 125:279-89. [PMID: 10817915 DOI: 10.1016/s0305-0491(99)00180-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Collectins are a sub-family of C-type lectins from mammals and birds that are characterized by their collagen-like domains. The mammalian collectin, mannose binding lectin, has attracted considerable interest because it can activate complement components via a lectin-mediated complement pathway that is independent of immunoglobulins. In this study, we have identified a calcium-dependent lectin from the invertebrate (tunicate), Styela plicata, that bears substantial similarities to mammalian collectins. The tunicate lectin, which was isolated by carbohydrate affinity chromatography, has a reduced apparent molecular mass of 43 kDa. The 43 kDa reduced polypeptide appeared as dimers, trimers and hexamers when analyzed by non-reducing and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis, while gel filtration suggested that the native form of the protein was a nonamer. Amino acid sequence and amino acid composition analysis revealed obvious similarities between the tunicate lectin and mammalian collectins, notably the inclusion of a collagenous domain and a short, cysteine bearing N-terminal domain. The identification of a collectin-like protein in an invertebrate such as S. plicata, which does not express immunoglobulin, indicates that lectin-mediated complement pathways may predate the origin of antibodies.
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Knight S, Bermingham MA, Mahajan D. Regular non-vigorous physical activity and cholesterol levels in the elderly. Gerontology 1999; 45:213-9. [PMID: 10394079 DOI: 10.1159/000022090] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND High-density lipoprotein cholesterol (HDL-C) is a powerful independent risk factor for coronary heart disease (CHD) among the elderly. Regular vigorous physical activity has been found to raise the concentration of HDL-C and thus reduce the risk of CHD. There is little data on the effect of non-vigorous activity on HDL-C in the elderly. OBJECTIVE The aim of this study was to compare CHD risk factors, especially HDL-C, in a group of elderly persons who engage in regular non-vigorous physical activity with a group of frail elderly examined in a previous study. METHODS Each subject (51 women and 19 men) had anthropometric measures taken and completed a questionnaire on lifestyle and medical history. Total cholesterol (TC), HDL-C and lipoprotein (a) were analysed. Results were compared with those of a frail group examined previously using similar methodology. RESULTS HDL-C, adjusted for age, body mass index (BMI) and waist-to-hip ratio (WHR), was greater among women (p < 0.01) and men (p < 0.05) who were engaged in a regular physical activity at least once a week. TC was higher among active women (p < 0.001), but there was also a trend towards a lower TC/HDL ratio. Therefore, although TC is higher in active women, this could be due to a higher proportion of the cholesterol fraction consisting of HDL-C. WHR was negatively associated with HDL-C in frail men (p < 0. 05), active men (p < 0.01) and active women (p < 0.05). BMI was negatively associated with HDL-C in frail women (p < 0.05). CONCLUSIONS This sample of elderly people who participate in regular weekly non-vigorous physical activity have a higher HDL-C than frail individuals who do little or no exercise. Since HDL-C is consistently reported to be inversely associated with CHD in the elderly, an elevation in HDL-C concentration may provide some protection to elderly persons who participate in regular nonvigorous physical activity compared to frail elderly individuals who are largely sedentary. Caution should be exercised in the interpretation of a TC only reading in active elderly women without an accompanying measure of HDL.
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