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1.
Space Sci Rev ; 218(1): 4, 2022.
Article in English | MEDLINE | ID: mdl-35194256

ABSTRACT

The Emirates Mars Mission (EMM) was launched to Mars in the summer of 2020, and is the first interplanetary spacecraft mission undertaken by the United Arab Emirates (UAE). The mission has multiple programmatic and scientific objectives, including the return of scientifically useful information about Mars. Three science instruments on the mission's Hope Probe will make global remote sensing measurements of the Martian atmosphere from a large low-inclination orbit that will advance our understanding of atmospheric variability on daily and seasonal timescales, as well as vertical atmospheric transport and escape. The mission was conceived and developed rapidly starting in 2014, and had aggressive schedule and cost constraints that drove the design and implementation of a new spacecraft bus. A team of Emirati and American engineers worked across two continents to complete a fully functional and tested spacecraft and bring it to the launchpad in the middle of a global pandemic. EMM is being operated from the UAE and the United States (U.S.), and will make its data freely available.

2.
Blood Cells Mol Dis ; 36(2): 259-64, 2006.
Article in English | MEDLINE | ID: mdl-16458028

ABSTRACT

The human ribosomal protein S19 gene (RPS19) is mutated in approximately 20% of patients with Diamond-Blackfan anemia (DBA), a congenital disease with a specific defect in erythropoiesis. The clinical expression of DBA is highly variable, and subclinical phenotypes may be revealed by elevated erythrocyte deaminase (eADA) activity only. In mice, complete loss of Rps19 results in early embryonic lethality whereas Rps19+/- mice are viable and without major abnormalities including the hematopoietic system. We have performed a detailed analysis of the Rps19+/- mice. We estimated the Rps19 levels in hematopoietic tissues and we analyzed erythrocyte deaminase activity and globin isoforms which are used as markers for DBA. The effect of a disrupted Rps19 allele on a different genetic background was investigated as well as the response to erythropoietin (EPO). From our results, we argue that the loss of one Rps19 allele in mice is fully compensated for at the transcriptional level with preservation of erythropoiesis.


Subject(s)
Anemia, Diamond-Blackfan/genetics , Erythropoiesis/genetics , Ribosomal Proteins/genetics , Animals , Biomarkers/analysis , Erythropoietin/pharmacology , Heterozygote , Mice , Mice, Knockout , Ribosomal Proteins/deficiency , Transcription, Genetic
3.
J Diabetes Complications ; 15(5): 250-6, 2001.
Article in English | MEDLINE | ID: mdl-11522499

ABSTRACT

Plasma activity of the enzyme semicarbazide-sensitive amine oxidase (SSAO) is high in diabetes. Production of angiotoxic substances (an aldehyde, hydrogen peroxide, and ammonia) in vessel walls is catalysed by SSAO, suggesting a role for SSAO in the development of complications of diabetes. The objective of the present study was to follow up plasma SSAO activity (measured radiometrically), HbA(1c) (using ion exchange chromatography), and retinopathy (by fundus photography) after 2.8 years, in 34 patients with Type 2 diabetes. We also measured urinary levels of an SSAO substrate, methylamine, by fluorometric high-performance liquid chromatography (HPLC). As at baseline, plasma SSAO activity was now higher in subjects with retinopathy (mean 19.5) than in subjects without retinopathy (mean 16.0), 95% confidence interval (CI) for difference 0.6-6.3 nmol benzylamine ml(-1) plasma h(-1). SSAO activity had not changed significantly since baseline, mean difference -1.65 and 95% CI for difference -3.76 to 0.46 nmol benzylamine ml(-1) plasma h(-1). Mean HbA(1c) level remained higher for patients with retinopathy (now 7.9%) compared to those without retinopathy (6.1%), 95% CI for difference 0.6-3.0%. Comparing baseline and the present study, retinopathy was nonproliferative; level had worsened for five and improved for two patients. Urinary methylamine/creatinine ratio was lower in the group of patients with retinopathy (mean 0.99) than in those without retinopathy (mean 1.78), 95% CI for difference 0.1-1.5 microg mg(-1). The results of the present study are compatible with a role for SSAO in the development of diabetic retinopathy.


Subject(s)
Amine Oxidase (Copper-Containing)/blood , Diabetes Mellitus, Type 2/blood , Diabetic Retinopathy/blood , Diabetic Retinopathy/pathology , Aged , Creatinine/blood , Creatinine/urine , Diabetes Mellitus, Type 2/urine , Diabetic Retinopathy/urine , Female , Follow-Up Studies , Fundus Oculi , Glycated Hemoglobin/analysis , Humans , Male , Methylamines/urine , Middle Aged , Photography
6.
Rapid Commun Mass Spectrom ; 14(14): 1184-94, 2000.
Article in English | MEDLINE | ID: mdl-10918366

ABSTRACT

The potential use of electrospray tandem mass spectrometry in the rapid characterisation of haemoglobin variants found in the Swedish population has been assessed. Analysis times of the order of 5 -10 min were routinely achieved, and identification of variants using mass spectrometry as the sole analytical technique was possible. However, additional information, readily available from isoelectric focusing experiments, made identification simpler and more secure. In the present communication we report on the identification of the alpha-chain variants, Hb Russ, Hb Le Lamentin and Hb Q-Iran. The identifications were confirmed by the use of nucleotide sequencing techniques.


Subject(s)
Globins/chemistry , Hemoglobins/chemistry , Genetic Variation , Globins/genetics , Hemoglobins/genetics , Humans , Mass Spectrometry/methods
7.
Transpl Immunol ; 4(4): 313-7, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8972562

ABSTRACT

The purpose of this study was to evaluate formulations based on surface active dietary lipids only as oral vehicles for cyclosporine. The absolute bioavailability of cyclosporine from two new lipid vehicles was determined in rats after intragastric administration and compared to that of Sandimmun oral solution, which contains non-ionic surface active substances in addition to dietary lipids. In the new vehicles, cyclosporine was dissolved in two different mixtures of glycerides from long-chained fatty acids. One mixture forms an L2-phase, an oil with very low interfacial tension towards water, and was administered both as the oily L2-phase and as a predispersed emulsion formulation. The other mixture forms a liquid crystalline phase and was administered only as an aqueous dispersion. The mean bioavailability of cyclosporine from Sandimmun was 8% while it was 34% from the L2-phase, 38% from the predispersed L2-phase and 27% from the dispersed liquid crystalline phase. The coefficients of variation in area under the blood concentration curve after administration of the two formulations based on the L2-phase were quite low (31% for the L2-phase and 24% for the predispersed L2-phase) and comparable to that after intravenous administration (24%), while the dispersed liquid crystalline phase gave a higher variability (91%), comparable to that of Sandimmun oral solution (101%). The low variabilities found with the two L2-phase vehicles suggest that this formulation is "self-emulsifying' in the gastrointestinal tract. Since the L2-phase is based on dietary lipids only, it is expected to be well tolerated and could prove to be a good vehicle for long-term clinical use of oral cyclosporine.


Subject(s)
Cyclosporine/pharmacokinetics , Glycerides/pharmacology , Intestinal Absorption/drug effects , Plant Oils/pharmacology , Surface-Active Agents/pharmacology , Administration, Oral , Animals , Biological Availability , Caseins/pharmacology , Chemical Phenomena , Chemistry, Physical , Cyclosporine/administration & dosage , Emulsions , Glycerides/administration & dosage , Male , Pharmaceutical Vehicles , Plant Oils/administration & dosage , Rats , Solvents/pharmacology , Sonication , Sunflower Oil , Surface Tension/drug effects , Surface-Active Agents/administration & dosage , Suspensions
10.
Am J Hematol ; 51(1): 32-6, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8571935

ABSTRACT

An abnormal hemoglobin with increased oxygen affinity, Hb Malmö [alpha 2 beta 297(FG4)His-->Gln], was found to cause erythrocytosis in two apparently unrelated Swedish families. Direct nucleotide sequencing of amplified DNA demonstrated a CAC-->CAA substitution in one family and a CAC-->CAG substitution in the other. Both mutations resulted in a His-->Gln substitution in codon 97. This finding prompted us to examine the possible point mutations underlying the different hemoglobin variants reported in the literature.


Subject(s)
Codon/genetics , Globins/genetics , Hemoglobinopathies/genetics , Point Mutation , Polycythemia/genetics , Adult , Amino Acid Sequence , Base Sequence , Female , Haplotypes , Hemoglobinopathies/ethnology , Hemoglobins, Abnormal/genetics , Humans , Male , Middle Aged , Molecular Sequence Data , Polycythemia/ethnology , Sweden/epidemiology
11.
Am J Hematol ; 48(3): 158-62, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7864023

ABSTRACT

An initiation codon mutation ATG-->ATA of the beta-globin gene was found in seven members of three generations of a family living in northern Sweden. This mutation, which has not previously been described, changes the initiation codon for methionine into a codon for isoleucine and will then result in a beta zero-thalassemic phenotype. The affected family members all present hematological findings typical for beta-thalassemic trait, with slight anemia, marked microcytosis, and increased levels of Hb A2.


Subject(s)
Globins/genetics , beta-Thalassemia/genetics , Adolescent , Adult , Aged , Amino Acid Sequence , Base Sequence , Child, Preschool , Female , Hemolysis , Humans , Iron/blood , Male , Molecular Sequence Data , Mutation , Pedigree , Peptide Chain Initiation, Translational , Sweden , beta-Thalassemia/blood
13.
Eur J Haematol ; 53(1): 21-5, 1994 Jul.
Article in English | MEDLINE | ID: mdl-7914875

ABSTRACT

Erythrocytosis is sometimes caused by the presence of haemoglobin (Hb) variants with increased oxygen affinity. Here we describe a beta-globin variant found by isoelectric focusing (IEF) of Hb from a 23-year-old Swedish male with moderate erythrocytosis. Amplification of DNA corresponding to the beta-globin gene and subsequent nucleotide sequencing revealed heterozygosity for a GTG-->GAG mutation at codon 20, thus suggesting a Val-->Glu substitution, which was confirmed at the protein level. This mutation occurs at the same position as Hb Olympia [beta 20(B2)Val-->Met], another variant associated with erythrocytosis due to increased oxygen affinity. The novel variant, Hb Trollhättan [beta 20(B2)Val-->Glu], which was also associated with increased oxygen affinity, was shown to be present in three generations of the patient's family.


Subject(s)
Glutamates , Hemoglobins, Abnormal/metabolism , Oxygen/blood , Polycythemia/blood , Valine , Adult , Amino Acid Sequence , Base Sequence , Codon , DNA/chemistry , Globins/genetics , Glutamic Acid , Haplotypes , Hemoglobins, Abnormal/genetics , Humans , Male , Molecular Sequence Data , Mutation , Polycythemia/genetics , Sweden
14.
Eur J Haematol ; 52(3): 156-61, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8168595

ABSTRACT

Three independent cases of chronic haemolytic anaemia in Sweden have recently been demonstrated to be due to the unstable haemoglobin variant Hb Köln. The patients, all of whom have partially compensated chronic haemolytic anaemia, presented with aggravated haemolysis during acute infections in childhood. In one case, acute B19 parvovirus infection induced an aplastic crisis. The substitutions all seem to have occurred as de novo mutations. Diagnosis was based on haemoglobin instability testing and isoelectric focusing of haemoglobin dimers. The final identification procedure for the substitutions included extraction of DNA from whole blood, polymerase chain reaction (PCR) amplification of parts of the beta-globin gene and nucleotide sequencing of the resulting material, or studies of restriction length polymorphisms (RFLPs) using the restriction endonucleases Mae II or Nla III. The use of PCR-RFLP is recommended as a valuable tool for diagnosing Hb Köln.


Subject(s)
Anemia, Hemolytic, Congenital/diagnosis , Hemoglobins, Abnormal/genetics , Adult , Amino Acid Sequence , Anemia, Hemolytic, Congenital/genetics , Base Sequence , Child , DNA Primers/chemistry , Female , Globins/genetics , Humans , Infant , Male , Molecular Sequence Data , Mutation , Pedigree , Restriction Mapping
16.
Hemoglobin ; 17(4): 303-18, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8226093

ABSTRACT

Here we report the occurrence of five different beta chain hemoglobin variants not previously described in Sweden. The variants were found during quantification of HbA1c using ion exchange high performance liquid chromatography (HPLC) or isoelectrofocusing. Samples were examined either at protein level by separation of globin chains on C8 reversed phase HPLC, digestion with trypsin or lysylendopeptidase and separation of peptides by C18 reversed phase HPLC, or at DNA level by direct nucleotide sequencing of double-stranded DNA fragments amplified from exon 1 + 2 of the beta-globin gene. The variants were: Hb Raleigh [beta 1 (NA1)Val-->Ac-Ala], Hb J-Baltimore [beta 16(A13)Gly-->Asp], Hb Tacoma [beta 30(B12)Arg-->Ser], Hb K-Ibadan [beta 46(CD5)Gly-->Glu], and Hb Fukuyama [beta 77(EF1)His-->Tyr]. Hb Tacoma, Hb K-Ibadan, and Hb Fukuyama were slightly unstable in the isopropanol test, but no signs of hemolysis were found in the patients who all had normal hematological findings.


Subject(s)
Genetic Variation , Globins/genetics , Glycated Hemoglobin/analysis , Hemoglobins, Abnormal/genetics , Adolescent , Adult , Blood Protein Electrophoresis , Chromatography, High Pressure Liquid , Diabetes Mellitus/blood , Female , Finland/ethnology , Hemoglobin J/analysis , Hemoglobins, Abnormal/analysis , Humans , Isoelectric Focusing , Male , Middle Aged , Mutation , Sweden
17.
Hemoglobin ; 17(3): 201-8, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8330972

ABSTRACT

An abnormal variant comprising approximately 39% of total hemoglobin was found in a 48-year-old Swedish woman. The variant was eluted from ion exchange high performance liquid chromatography (HPLC) used for routine quantification of Hb A1c at a position similar to Hb S. Amplification of beta-globin exons and nucleotide sequencing revealed heterozygosity for a GAT-->CAT mutation in codon 21, corresponding to the amino acid substitution Asp-->His at position 21. This mutation was confirmed by amino acid composition and peptide sequence determinations. Substitutions in this position are not likely to affect the function of the hemoglobin molecule and the hemoglobin variant, for which the name Hb Karlskoga is proposed, was not associated with any overt hematological abnormalities.


Subject(s)
Globins/genetics , Hemoglobins, Abnormal/genetics , Amino Acid Sequence , Base Sequence , Chromatography, High Pressure Liquid , Codon , DNA Mutational Analysis , Female , Hemoglobins, Abnormal/isolation & purification , Humans , Middle Aged , Molecular Sequence Data , Sweden
18.
J Intern Med ; 233(3): 299-302, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8450301

ABSTRACT

A 38-year-old Swedish woman was investigated because of mild anaemia resistant to iron therapy. Mild haemolytic disease was found by routine blood tests. Neither HPLC (HbA1c quantification) nor Hb-electrofocusing revealed any major abnormal fraction, although in vitro testing of haemoglobin instability indicated the presence of unstable haemoglobin. PCR was used to amplify coding regions of the beta globin gene. Direct nucleotide sequencing of this material revealed heterozygosity for a substitution corresponding to the haemoglobin variant alpha 2 beta 2 135(H13)Ala-->Pro. This clearly unstable variant, named Hb Altdorf, has earlier been described only in a family of Italian descent. Examination of beta globin genes from six family members of the proposita by PCR followed by specific cleavage with the restriction enzyme Ban I, revealed the mutation in her two children but not in her parents or siblings. This case demonstrates that haemoglobin variants can not be ruled out as a cause of haematological disease even if the parents lack symptoms and standard tests, such as HPLC and electrophoresis/electrofocusing, do not reveal major abnormalities.


Subject(s)
Anemia, Hemolytic/genetics , Hemoglobins, Abnormal/genetics , Adult , Anemia, Hemolytic/blood , Female , Globins/genetics , Hemoglobins, Abnormal/analysis , Humans , Pedigree , Polymerase Chain Reaction
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