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Blumenfeld R, Edwards SF, Schwartz M. da Vinci fluids, catch-up dynamics and dense granular flow. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2010; 32:333-338. [PMID: 20668906 DOI: 10.1140/epje/i2010-10628-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Accepted: 06/24/2010] [Indexed: 05/29/2023]
Abstract
We introduce and study a da Vinci fluid, a fluid whose dissipation is dominated by solid friction. We analyse the flow rheology of a discrete model and then coarse-grain it to the continuum. We find that the model gives rise to behaviour that is characteristic of dense granular fluids. In particular, it leads to plug flow. We analyse the nucleation mechanism of plugs and their development. We find that plug boundaries generically expand and we calculate the growth rate of plug regions. In systems whose internal effective dynamic and static friction coefficients are relatively uniform we find that the linear size of plug regions grows as (time)¹(/)³ . The suitability of the model to granular materials is discussed.
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Allen F, Schwartz M. THE EFFECT OF STIMULATION OF THE SENSES OF VISION, HEARING, TASTE, AND SMELL UPON THE SENSIBILITY OF THE ORGANS OF VISION. ACTA ACUST UNITED AC 2010; 24:105-21. [PMID: 19873196 PMCID: PMC2142069 DOI: 10.1085/jgp.24.1.105] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Wong SJ, Chen AY, Curran WJ, Garden AS, Harari PM, Murphy BA, Bellm LA, Schwartz M, Ang K. Longitudinal Oncology Registry of Head and Neck Carcinoma (LORHAN): Findings related to the oropharynx. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.5585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Harari PM, Chen AY, Curran WJ, Garden AS, Murphy BA, Wong SJ, Bellm LA, Schwartz M, Schneider C, Ang K. Longitudinal Oncology Registry of Head and Neck Carcinoma (LORHAN): First overview of complete data set. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.5584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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80
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Schwartz M, Shechter R. Protective autoimmunity functions by intracranial immunosurveillance to support the mind: The missing link between health and disease. Mol Psychiatry 2010; 15:342-54. [PMID: 20332793 DOI: 10.1038/mp.2010.31] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Circulating immune cells support hippocampal neurogenesis, spatial memory, expression of brain-derived neurotrophic factor, and resilience to stress. Nevertheless, considering the immune privileged status of the central nervous system (CNS), such cells were assumed to be excluded from the healthy brain. It is evident, however, that the CNS is continuously surveyed by leukocytes, though their function is still a mystery. Coupling this routine leukocyte trafficking with the function attributed to circulating T cells in brain plasticity led us to propose here that CNS immunosurveillance is an integral part of the functioning brain. Anatomical restriction of selected self-recognizing leukocytes to the brain's borders and fluids (cerebrospinal fluid) not only supports the brain's activity, but also controls the potential aggressiveness of such cells. Accordingly, the brain's 'privilege' is its acquisition of a private peripheral immunological niche under its own control, which supports brain function. Immune malfunction may comprise a missing link between a healthy and diseased mind.
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81
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Schwartz M. Microbes or man, who will win? Acta Gastroenterol Belg 2010; 73:37-40. [PMID: 20458848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Johannsen TH, Ripa CPL, Carlsen E, Starup J, Nielsen OH, Schwartz M, Drzewiecki, Mortensen EL, Main KM. Long-Term Gynecological Outcomes in Women with Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency. INTERNATIONAL JOURNAL OF PEDIATRIC ENDOCRINOLOGY 2010. [DOI: 10.1186/1687-9856-2010-784297] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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del Pozo AC, Martín JDR, Rodriguez-Laiz G, Sturdevant M, Iyer K, Schwartz M, Schiano T, Lerner S, Ames S, Bromberg J, Thung S, de Boccardo G. Outcome of combined liver and kidney transplantation in hepatitis C: a single-center long-term follow-up experience. Transplant Proc 2009; 41:1713-6. [PMID: 19545713 DOI: 10.1016/j.transproceed.2009.02.103] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Accepted: 02/23/2009] [Indexed: 12/26/2022]
Abstract
INTRODUCTION Hepatitis C (HCV) cirrhosis is the prevalent liver disease requiring liver transplantation in the United States. Candidates who also have end-stage renal disease, chronic renal disease stage 4, or prolonged hepatorenal syndrome are considered for combined liver and kidney transplantation (CLKT). MATERIALS AND METHODS We performed a retrospective study of HCV(+) and HCV(-) CLKT patients with more than 12 months of follow-up and HCV(+) patients with isolated liver transplant (OLT) to compare the outcomes of various groups. RESULTS Since 1988, 2983 OLTs were performed at our institution including 58 CLKTs. Of these, 23 were HCV(+) subjects who were significantly older than HCV(-) CLKT patients. Race, pretransplant dialysis time, renal indication for CLKT, Model for End-stage Liver Disease score, donor age, liver and kidney rejection as well as occurrence of posttransplant hypertension were similar among HCV(+) and HCV(-) CLKT patients. Posttransplant diabetes was observed in 80% of the HCV(+) group and 30% of the HCV(-) group (P = .01). Renal function seemed to be better in HCV(-) when compared with HCV(+) subjects at 5 years (P = .09). Overall patient survival for HCV(+) CLKT, HCV(-) CLKT, and HCV(+) OLT groups at 1, 2, and 5 years were not significantly different (P = .6). CONCLUSION HCV positivity should not exclude appropriate candidates for CLKT.
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Schwartz M, Puff C, Stein VM, Baumgärtner W, Tipold A. Marked MMP-2 transcriptional up-regulation in mononuclear leukocytes invading the subarachnoidal space in aseptic suppurative steroid-responsive meningitis-arteritis in dogs. Vet Immunol Immunopathol 2009; 133:198-206. [PMID: 19733404 DOI: 10.1016/j.vetimm.2009.08.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 07/23/2009] [Accepted: 08/03/2009] [Indexed: 10/20/2022]
Abstract
Canine Steroid-Responsive Meningitis-Arteritis (SRMA) is a suitable animal model for studies on the development of neutrophilic pleocytosis in aseptic meningitis. Samples of dogs in the acute phase of SRMA (n=16) were examined for gene expression of matrix metalloproteinases (MMP)-2 and -9 and tissue inhibitors of metalloproteinases (TIMP)-1 and -2. Results were compared to those of dogs under glucocorticosteroid treatment for SRMA (n=16) and dogs with other inflammatory and neoplastic diseases of the central nervous system (CNS) (n=19). Samples included mononuclear (PBMCs) and polymorphonuclear cells (PBPMNs) of peripheral blood and cerebrospinal fluid white blood cells (CSF WBCs). In the acute phase of SRMA CSF WBCs showed mRNA expression for MMP-2 and -9 and TIMP-1 and -2, highlighting a contribution of these cells to the overall content of MMPs and TIMPs in CSF. MMP-2 mRNA levels in CSF WBCs were significantly up-regulated in comparison to PBMC expression levels, suggesting that MMP-2 is relevant for PBMC invasion into the subarachnoidal space and that the expression is influenced by migratory activity through the blood-CSF-barrier.
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Bregman DJJ, Rozumalski A, Koops D, de Groot V, Schwartz M, Harlaar J. A new method for evaluating ankle foot orthosis characteristics: BRUCE. Gait Posture 2009; 30:144-9. [PMID: 19520576 DOI: 10.1016/j.gaitpost.2009.05.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2009] [Revised: 04/28/2009] [Accepted: 05/18/2009] [Indexed: 02/02/2023]
Abstract
The mechanical characteristics of ankle foot orthoses (AFOs), such as the stiffness and neutral angle around the ankle and metatarsal-phalangeal (MTP) joints, are rarely quantified. Paradoxically, it is expected that these characteristics determine the function of the AFO in pathological gait. Therefore a device to determine these AFO characteristics named BRUCE was designed based on multidisciplinary consensus. The design is based on a replicated human leg that is manually driven and continuously registers joint configuration and force exerted by the AFO onto the device. From this information, neutral angles and stiffnesses around the ankle and MTP joints are determined using a linear fit. The reliability of the stiffnesses and neutral angles was studied by repeatedly measuring the mechanical characteristics of four different AFOs, and evaluating the inter-session, intra-session, and inter-observer errors. The reliability study revealed that ankle and MTP stiffness could be measured with very high reliability (ICC=0.98-1.00). Ankle and MTP neutral angles showed reasonable reliability (ICC=0.79-0.92). Measurement error in the neutral angles could mainly be attributed to the difference in testers. With a fixed tester excellent reliability was obtained (ICC=0.99-0.99). The results derived using BRUCE can help to gain insight into the role of the mechanical characteristics of AFOs in correcting pathological gait. Objective information of AFO characteristics is expected to lead to a better founded prescription of AFOs, resulting in optimal functional benefit for the patient.
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Lindquist SG, Schwartz M, Batbayli M, Waldemar G, Nielsen JE. Genetic testing in familial AD and FTD: mutation and phenotype spectrum in a Danish cohort. Clin Genet 2009; 76:205-9. [PMID: 19659892 DOI: 10.1111/j.1399-0004.2009.01191.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Autosomal dominantly transmitted Alzheimer's disease (AD) and frontotemporal dementia (FTD) are genetically heterogeneous disorders. To date, three genes have been identified in which mutations cause early-onset autosomal dominant inherited AD: APP, PSEN1, and PSEN2. Mutations in two genes on chromosome 17, the MAPT and the PGRN genes, are associated with autosomal dominant inherited FTD. The aim of this study was to characterize the mutation spectrum and describe genotype-phenotype correlations in families with inherited dementia. The identification of novel mutations and/or atypical genotype-phenotype correlations contributes to further characterizing the disorders. DNA-samples from the 90 index cases from a Danish referral-based cohort representing families with presumed autosomal dominant inherited AD or FTD were screened for mutations in the known genes with sequencing, denaturing high-performance liquid chromatography (DHPLC) and multiplex ligation-dependent probe amplification (MLPA) techniques. Seven presumed pathogenic mutations (two PSEN1, one PSEN2, one APP, one MAPT, and two PGRN) were identified, including a novel PSEN2 mutation (V393M). No dosage aberrations were identified.
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Didenko M, Stein KM, Starchik D, Khubulava G, Verlato R, Massa R, Botto G, Amellone C, Perucca A, Bongiorni MG, Piacenti M, Corbucci G, Weiss R, Rhodes T, Khoo M, Dinerman J, Oza A, Hoyt RH, Marcus RH, Mchenry B, Fedewa MM, Wiegand U, Kaplan AJ, Gras D, Cazzin R, Schwartz M, Jauvert G, Prakash A, Mansourati J, Sadoul N, Aime E, Goethals P, Bordier S, Wiegand U. Abstracts: EP meets CP: pacing for atrial fibrillation. Europace 2009. [DOI: 10.1093/europace/euq250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Schwartz M, Rosenberg T. Prenatal diagnosis of choroideremia. ACTA OPHTHALMOLOGICA SCANDINAVICA. SUPPLEMENT 2009:33-6. [PMID: 8741114 DOI: 10.1111/j.1600-0420.1996.tb00381.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
With the mapping of the locus CHM for choroideremia and the subsequent cloning of the gene, reliable carrier and prenatal diagnosis has become a possibility. We discuss our experience with prenatal diagnosis of choroideremia, an X-linked choroidoretinal dystrophy leading to blindness in otherwise healthy males. In the period 1987-1995, five prenatal diagnoses have been performed by either indirect linkage analysis or by detection of the disease-causing mutation, reflecting the impact of molecular biology in clinical genetic practice.
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Jeppesen TD, Dunø M, Schwartz M, Krag T, Rafiq J, Wibrand F, Vissing J. Short- and long-term effects of endurance training in patients with mitochondrial myopathy. Eur J Neurol 2009; 16:1336-9. [PMID: 19486129 DOI: 10.1111/j.1468-1331.2009.02660.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND PURPOSE It is unknown whether prolonged training is a safe treatment to alleviate exercise intolerance in patients with mitochondrial DNA (mtDNA) mutations. METHODS The effect of 3 and 12 months training and 3-12 months deconditioning was studied in four patients carrying different mtDNA mutations. RESULTS Three-month moderate-intensity training increased oxidative capacity by 23%, which was sustained after 6-12 months of low-intensity training. Training and deconditioning did not induce adverse effects on clinical symptoms, muscle morphology and mtDNA mutation load in muscle. CONCLUSION Long-term training effectively improves exercise capacity in patients with mitochondrial myopathy, and appears to be safe.
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Curran WJ, Chen AY, Garden AS, Harari P, Murphy BA, Wong S, Bellm LA, Schwartz M, Dawson D, Ang KK. Longitudinal oncology registry of head and neck carcinoma (LORHAN): First report of outcomes. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.6071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
6071 Background: Registries can be invaluable for describing patterns of care and outcomes for a population of patients (pts). We report the initial survival findings from LORHAN, a prospective, longitudinal, observational national registry of head and neck carcinoma (HNC) pts. Methods: Pts are eligible for LORHAN if they have newly diagnosed HNC, are scheduled to receive radiotherapy (RT) or drug therapy, are ≥18 years of age and have provided written informed consent. Data are entered in the registry electronically and transferred via Secure HTTP protocols. Patient confidentiality is strictly maintained. Pts are followed from time of initial diagnosis and for a minimum of 2 and up to 10 years. When information is complete and has been verified and signed off by the investigator, a record is locked. Only locked records are summarized and reported. Results: 2,354 pts have been enrolled in LORHAN since Dec. 2005. Of these, 1,326 pts have completed initial cancer treatment and have locked records. 1- and 2-year follow-up data are available for 583 and 56 pts, respectively. Baseline characteristics were similar between settings, except that pts treated at academic centers were significantly younger (58 vs. 62 years of age), had poorer performance status (mean Zubrod: 0.9 vs. 0.7), had fewer laryngeal tumors (17% vs. 27% of pts) but more oropharyngeal tumors (42% vs. 37% of pts) and presented with more advanced disease (stage IV: 70% vs. 48% of pts) compared to pts treated in community. Treatment did not differ by setting. Treatment and survival data are shown below. Conclusions: LORHAN demonstrates it is feasible to collect more detailed information about patient and tumor features and treatment other than surgery. Changes in the pattern of care and survival findings are expected to emerge as newer regimens, including IC and targeted agents, are incorporated more broadly into clinical practice, and data in LORHAN matures. [Table: see text] [Table: see text]
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Olesen H, Hom BL, Schwartz M. Antibody to Transcobalamin II in Patients Treated with Long Acting Vitamin B12 Preparations. ACTA ACUST UNITED AC 2009. [DOI: 10.1111/j.1600-0609.1968.tb01712.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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92
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Schwartz M, Bastrup-Madsen P. A new vitamin B12 binding protein in serum causing excessively high serum vitamin B12 values. SCANDINAVIAN JOURNAL OF HAEMATOLOGY 2009; 5:35-40. [PMID: 4174291 DOI: 10.1111/j.1600-0609.1968.tb01715.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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93
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94
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Hippe E, Schwartz M. Intrinsic factor activity of stomach preparations from various animal species. SCANDINAVIAN JOURNAL OF HAEMATOLOGY 2009; 8:276-81. [PMID: 5134474 DOI: 10.1111/j.1600-0609.1971.tb00876.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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95
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Hom BL, Olesen H, Schwartz M. Turnover of 57Co-labelled vitamin B12-transcobalamin II and autologous 131-I-labelled IgG in a patient with antibody to transcobalamin II. SCANDINAVIAN JOURNAL OF HAEMATOLOGY 2009; 5:107-15. [PMID: 4175218 DOI: 10.1111/j.1600-0609.1968.tb01725.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Schwartz M, Boettcher IC, Kramer S, Tipold A. Two dogs with iatrogenic discospondylitis caused by meticillin-resistantStaphylococcus aureus. J Small Anim Pract 2009; 50:201-5. [DOI: 10.1111/j.1748-5827.2008.00720.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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97
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Bisgaard AM, Kirchhoff M, Nielsen JE, Kibaek M, Lund A, Schwartz M, Christensen E. Chromosomal deletion unmasking a recessive disease: 22q13 deletion syndrome and metachromatic leukodystrophy. Clin Genet 2009; 75:175-9. [DOI: 10.1111/j.1399-0004.2008.01113.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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98
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Schwartz M, London A, Shechter R. Boosting T-cell immunity as a therapeutic approach for neurodegenerative conditions: The role of innate immunity. Neuroscience 2009; 158:1133-42. [DOI: 10.1016/j.neuroscience.2008.12.013] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 12/09/2008] [Accepted: 12/10/2008] [Indexed: 12/14/2022]
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99
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Ron-Harel N, Segev Y, Lewitus GM, Cardon M, Ziv Y, Netanely D, Jacob-Hirsch J, Amariglio N, Rechavi G, Domany E, Schwartz M. Age-dependent spatial memory loss can be partially restored by immune activation. Rejuvenation Res 2009; 11:903-13. [PMID: 18803478 DOI: 10.1089/rej.2008.0755] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Aging is often associated with a decline in hippocampus-dependent spatial memory. Here, we show that functional cell-mediated immunity is required for the maintenance of hippocampus-dependent spatial memory. Sudden imposition of immune compromise in young mice caused spatial memory impairment, whereas immune reconstitution reversed memory deficit in immune-deficient mice. Analysis of hippocampal gene expression suggested that immune-dependent spatial memory performance was associated with the expression of insulin-like growth factor (Igf1) and of genes encoding proteins related to presynaptic activity (Syt10, Cplx2). We further showed that memory loss in aged mice could be attributed to age-related attenuation of the immune response and could be reversed by immune system activation. Homeostatic-driven proliferation of lymphocytes, which expands the existing T cell repertoire, restored spatial memory deficits in aged mice. Thus, our results identify a novel function of the immune system in the maintenance of spatial memory and suggest an original approach for arresting or reversing age-associated memory loss.
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Ekelund CK, Skibsted L, Søgaard K, Main KM, Dziegiel MH, Schwartz M, Moeller N, Roos L, Tabor A. Dizygotic monochorionic twin pregnancy conceived following intracytoplasmic sperm injection treatment and complicated by twin-twin transfusion syndrome and blood chimerism. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2008; 32:832-834. [PMID: 18956441 DOI: 10.1002/uog.6221] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report a case of a dizygotic monochorionic twin pregnancy preceded by intracytoplasmic sperm injection treatment including assisted hatching. On ultrasound examination at 25 weeks' gestation the twins, which had been assumed to be monochorionic, were found to be of different sexes. Karyotyping and zygocity determination were performed on amniotic fluid and showed the twins to be dizygotic with normal female and male karyotypes. There were clinical and sonographic signs of twin-twin transfusion syndrome (TTTS), and Cesarean delivery was performed at 32 weeks' gestation. At birth the twins were phenotypically a normal male and a normal female. Histology of the placenta showed it to be monochorionic diamniotic. Blood chimerism was found postnatally as both infants had the karyotypes 46,XX[13]/46,XY[17]. Chimerism was not found in cells from a buccal swab at 6 months of age. This is one of only a few reported cases of dizygotic monochorionic twins. Nearly all of these cases have been conceived after assisted reproductive technology procedures. It is of clinical importance to be aware of this rare phenomenon in relation to TTTS, prenatal screening and parental counseling.
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