Reduced chondrogenic and adipogenic activity of mesenchymal stem cells from patients with advanced osteoarthritis

OBJECTIVE

Mesenchymal stem cells (MSCs) are resident in the bone marrow throughout normal adult life and have the capacity to differentiate along a number of connective tissue pathways, among them bone, cartilage, and fat. To determine whether functionally normal MSC populations may be isolated from patients with advanced osteoarthritis (OA), we have compared cells from patients undergoing joint replacement with cells from normal donors. Cell populations were compared in terms of yield, proliferation, and capacity to differentiate.

METHODS

MSCs were prepared from bone marrow aspirates obtained from the iliac crest or from the tibia/femur during joint surgery. In vitro chondrogenic activity was measured as glycosaminoglycan and type II collagen deposition in pellet cultures. Adipogenic activity was measured as the accumulation of Nile Red O-positive lipid vacuoles, and osteogenic activity was measured as calcium deposition and by von Kossa staining.

RESULTS

Patient-derived MSCs formed colonies in primary culture that were characteristically spindle-shaped with normal morphology. The primary cell yield in 36 of 38 cell cultures from OA donors fell within the range found in cultures from normal donors. However, the proliferative capacity of patient-derived MSCs was significantly reduced. There was a significant reduction in in vitro chondrogenic and adipogenic activity in cultures of patient-derived cells compared with that in normal cultures. There was no significant difference in in vitro osteogenic activity. There was no decline in chondrogenic potential with age in cells obtained from individuals with no evidence of OA.

CONCLUSION

These results raise the possibility that the increase in bone density and loss of cartilage that are characteristic of OA may result from changes in the differentiation profile of the progenitor cells that contribute to the homeostatic maintenance of these tissues.

Insulin degludec: four times lower pharmacodynamic variability than insulin glargine under steady-state conditions in type 1 diabetes

AIMS

Insulin degludec (IDeg) is a new-generation basal insulin with an ultra-long duration of action. We compared the pharmacodynamic (PD) variability of IDeg and insulin glargine (IGlar) under steady-state conditions.

METHODS

Day-to-day variability in glucose-lowering effect was investigated in 54 subjects with type 1 diabetes who underwent a 24-h euglycaemic glucose clamp on the 6th, 9th and 12th day of treatment with 0.4 U/kg of IDeg or IGlar once daily. Within-subject variability was estimated using a linear mixed model on log-transformed PD endpoints derived from the glucose infusion rate (GIR) profiles during the clamps.

RESULTS

For IDeg the day-to-day variability in glucose-lowering effect was four-times lower than for IGlar for total metabolic effect (AUC(GIR,0-24h,SS), CV 20% vs. 82%) and for the last 22 h [AUC(GIR,2-24h,SS) (not influenced by intravenous insulin during the clamp), CV 22% vs. 92%]. Furthermore, lower variability in the maximum effect was observed for IDeg vs. IGlar (GIR(max,SS), CV 18% vs. 60%). The lower within-subject variability of IDeg was consistent over time (CVs of 33% for AUC(GIR,0-2h,SS), 32% for AUC(GIR,10-12h,SS) and 33% for AUC(GIR,22-24h,SS)), whereas the variability of IGlar was higher and increased substantially 8 h post-dosing (CVs of 60% for AUC(GIR,0-2h,SS), 135% for AUC(GIR,10-12h,SS) and 115% for AUC(GIR,22-24h,SS)).

CONCLUSIONS

These results show that IDeg has a significantly more predictable glucose-lowering effect from day to day than IGlar.

Coronary artery calcification in older adults to age 99: prevalence and risk factors

BACKGROUND

Coronary artery calcification has been proposed as a noninvasive method to assess cardiovascular disease (CVD) risk. However, the prevalence and risk factors for coronary artery calcification in populations >65 years have not been well studied.

METHODS AND RESULTS

Electron beam tomography was performed to assess coronary artery calcium (CAC) in 614 older adults aged, on average, 80 years (range, 67 to 99 years); 367 (60%) were women, and 143 (23%) were black. Calcium scores ranged from 0 to 5459. Median scores were 622 for men and 205 for women. Scores increased by age and were lower in blacks than in whites. Nine percent of subjects (n=57) had no CAC, and 31% (n=190) had a score lower than 100. A history of CVD was associated with calcium score. Age, male sex, white race, CVD, triglyceride level, pack-years of smoking, and asthma, emphysema, or bronchitis (chronic obstructive pulmonary disease) were independently associated with CAC score in the fourth quartile.

CONCLUSIONS

A wide range of CAC scores was observed, suggesting adaptation with aging. CAC may have potential to predict CVD in older adults, but this remains to be determined.

Society of pediatric liver transplantation: Current registry status 2011-2018

BACKGROUND

SPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies.

OBJECTIVE

To report the outcomes of the SPLIT registry from 2011 to 2018.

METHODS

This is a multicenter, cross-sectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18 years of age, received a first liver-only, a combined liver-kidney, or a combined liver-pancreas transplant during this study period.

RESULTS

A total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. Kaplan-Meier estimates of 1-year patient and graft survival were 97.3% and 96.6%. First 30 days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90 days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2 years of follow-up, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.

Usefulness of electron beam tomography to detect progression of coronary and aortic calcium in middle-aged women

Electron beam tomography (EBT) permits the noninvasive quantification of coronary and aortic calcium as a marker of atherosclerosis. Coronary and aortic calcium are strongly related to premenopausal cardiovascular risk factors in middle-aged women. This report evaluates changes in coronary and aortic calcium over an average of 18 months in 80 women. Measurement variation over time and between readings is also evaluated in these women who were followed through the menopausal transition. Eight years after menopause, 80 women (average age 63 years) underwent serial EBT of the coronary arteries and aorta separated by 18 months. Calcium scores were based on the number and density of calcific deposits. Duplicate readings were obtained to evaluate the effect of reading variation on calcium scores. At baseline, the median calcium score was 0 in the coronary arteries and 58 in the aorta. Average change in coronary (+11) and aortic (+112) calcium were significantly different from zero (p < 0.001). Reading variability did not contribute significantly to the variation in calcium scores. Extent of calcium in the coronary arteries was associated with progression of calcium in the aorta (p = 0.013). Both coronary and aortic calcium were significantly associated with premenopausal cardiovascular risk factors. Thus, progression of coronary and aortic calcium using EBT can be observed over a short time in healthy middle- aged women.

Reversion of a Chinese hamster cell auxotrophic mutant

A mutant cell strain derived from a Chinese hamster line by mutagenesis with ethylmethane sulfonate requires glycine for growth. In the wild type, glycine synthesis is catalyzed by serine hydroxymethyltransferase (EC 2.1.2.1). Cell fractionation by differential centrifugation and isopycnic sucrose gradient analysis reveals that the enzyme activity is found in both the mitochondrial and cytosol fractions. The specific activity in the mitochondrial fraction is about 20 times higher than in the cytosol, and is much more stable to thermal inactivation. The glycine-requiring mutant has lost all of the mitochondrial enzyme activity, while retaining the cytosol activity. The mutant is very stable but can be induced to revert by several chemical mutagens. One glycine-independent revertant induced by ethyl methane sulfonate was studied in detail. Serine hydroxymethyltransferase activity is again present in the mitochondrial fraction, at about [unk] of the wild-type level. However, the revertant mitochondrial enzyme exhibits an altered thermal sensitivity, with a half-life at 45 degrees of 55 min as compared to 180 min in the wild type. The half-life for the cytosol enzyme in all three strains is 7 min. Mixing experiments demonstrate that the heat lability of the revertant enzyme is not due to a dissociable factor in the extract. The data are consistent with the idea that the original mutation occurred in the structural gene for one isozyme of the enzyme and that the revertant has undergone a second mutation in this gene, partially restoring enzyme activity.

Laquinimod suppress antigen presentation in relapsing-remitting multiple sclerosis: in-vitro high-throughput gene expression study

Laquinimod (LAQ) is a new immunomodulatory drug shown to be effective in the treatment of relapsing-remitting multiple sclerosis (RRMS); however, its molecular target pathways are not well recognized. In this study we characterized in-vitro the molecular effects of LAQ in peripheral blood mononuclear cells (PBMC) of healthy subjects and RRMS patients by gene expression microarrays. We demonstrated that LAQ induced suppression of genes related to antigen presentation and corresponding inflammatory pathways. These findings were demonstrated mainly via the NFkB pathway. Analysis of PBMC subpopulations identified activation of Th2 response in CD14+ and CD4+ cells and suppression of proliferation in CD8+ cells.

Acute experimental allergic encephalomyelitis in radiation bone marrow chimeras between high and low susceptible strains of mice

Acute experimental allergic encephalomyelitis (EAE) is an autoimmune disease involving the central nervous system (CNS) that can be elicited in susceptible strains of mice by the subcutaneous inoculation of mouse spinal cord homogenate (MSCH) in conjunction with complete Freund's adjuvant. In order to localize the physiological compartment conveying susceptibility to mice for EAE induction, hematopoietic radiation chimeras were prepared between the highly responsive SJL and low responder B10.S strains. Upon challenge with SJL MSCH preparations, high incidence of clinical disease was exhibited by B10.S----SJL chimeras but not by SJL----B10.S mice, suggesting that non-bone-marrow-derived factors were influencing development of disease. The incidence of histological lesions in the CNS was high for virtually all experimental and control groups except normal B10.S and B10.S----B10.S reconstituted mice. In contrast, challenge with B10.S MSCH induced a high clinical incidence of EAE in both B10.S----SJL and SJL----B10.S chimeras, indicating a possible interstrain difference in the immunogenicity of relevant CNS antigens.

Acute reversal of pheochromocytoma-induced catecholamine cardiomyopathy

Pheochromocytoma is a rare neuroendocrine tumor. We report a case of pheochromocytoma-induced cardiomyopathy in an 18-year old white female. A review of the literature indicated that this is the most dramatic reversal of pheochromocytoma cardiomyopathy reported. With aggressive medical management, there was complete recovery of the hemodynamic, echocardiographic, and electrocardiographic abnormalities within 14 days. This case emphasizes the importance of aggressive and appropriate medical therapy in pheochromocytoma heart disease.

Anomalies of lateralization in man: a case of total situs inversus

Total or complete visceral situs inversus is the complete inversion of position of the thoracic and abdominal viscera. The aim of this study is to report a case of complete situs inversus and to review our knowledge of the anomalies of lateralization. A case of complete sinus inversus was discovered incidentally during anatomic dissection in a female subject aged 87 years. The thoracic and abdominal organs had a position symmetric with the normal. This was associated with a common mesentery and incomplete rotation of the colon, placing the cecum under the left lobe of the liver. These alimentary anomalies were discovered in adult life during a surgical operation for small intestinal occlusion, as evidenced by the abdominal scar and peritoneal adhesions. No cardiac, pulmonary, splenic or facial sinus anomalies were encountered. The incidence of complete situs inversus is estimated as 1/8000 in the general population. It may be isolated or associated with malformations, especially cardiac or alimentary. It may be discovered in infancy because of associated anomalies but often remains asymptomatic and discovered by chance in adult life. Complete situs inversus may form part of the multiple malformational syndromes such as that of Kartagener, with recessive autosomal transmission (complete situs inversus, bronchiectasis, chronic sinusitis, male infertility), which represents 20-25% of cases of complete situs inversus. In view of the frequency of this type of anomaly, a knowledge of anomalies of lateralization is essential in clinical practice.

Genomic signatures of strain selection and enhancement in Bacillus atrophaeus var. globigii, a historical biowarfare simulant

BACKGROUND

Despite the decades-long use of Bacillus atrophaeus var. globigii (BG) as a simulant for biological warfare (BW) agents, knowledge of its genome composition is limited. Furthermore, the ability to differentiate signatures of deliberate adaptation and selection from natural variation is lacking for most bacterial agents. We characterized a lineage of BGwith a long history of use as a simulant for BW operations, focusing on classical bacteriological markers, metabolic profiling and whole-genome shotgun sequencing (WGS).

RESULTS

Archival strains and two "present day" type strains were compared to simulant strains on different laboratory media. Several of the samples produced multiple colony morphotypes that differed from that of an archival isolate. To trace the microevolutionary history of these isolates, we obtained WGS data for several archival and present-day strains and morphotypes. Bacillus-wide phylogenetic analysis identified B. subtilis as the nearest neighbor to B. atrophaeus. The genome of B. atrophaeus is, on average, 86% identical to B. subtilis on the nucleotide level. WGS of variants revealed that several strains were mixed but highly related populations and uncovered a progressive accumulation of mutations among the "military" isolates. Metabolic profiling and microscopic examination of bacterial cultures revealed enhanced growth of "military" isolates on lactate-containing media, and showed that the "military" strains exhibited a hypersporulating phenotype.

CONCLUSIONS

Our analysis revealed the genomic and phenotypic signatures of strain adaptation and deliberate selection for traits that were desirable in a simulant organism. Together, these results demonstrate the power of whole-genome and modern systems-level approaches to characterize microbial lineages to develop and validate forensic markers for strain discrimination and reveal signatures of deliberate adaptation.

In vivo electron spin resonance in rats

In vivo ESR studies have been made on Wistar and Sprague-Dawley rats using travelling wave helices implanted in the left lobe of the liver. Tissue regenerates completely around the Teflon-enclosed turns of the coil and histological studies have shown that it is composed of liver cells and connective tissue. Electron spin resonance studies of this tissue in vitro reported by Commoner and Ternberg in 1961 have demonstrated that it exhibits the 'tissue radical' signal. The implanted coils have detected, in vivo, a three-line spectrum due to a strong concentration of 4-hydroxy- 2,2,6,6-tetramethylpiperidine-1-oxyl free radical ('tempol'), a nitroxide spin label, injected either intramuscularly, intraperitoneally or intravenously into the experimental animal immediately prior to the measurement. They have also detected, in vivo, a similar three-line spectrum due to 'spin-labelled chlorpromazine', a tranquillizing drug to which this nitroxide spin label has been attached, injected intramuscularly or intraperitoneally into the animal immediately prior o the measurement. Work is currently in progress to increase the in vivo sensitivity of the implanted helices by menas of improved coupling techniques and the use of a time-averaging computer.

Broad-spectrum antiviral activity of the acyclic guanosine phosphonate (R,S)-HPMPG

(R,S)-9-(3-hydroxy-2-phosphonomethoxypropyl)guanine [(R,S)-HPMPG] exhibits broad spectrum antiviral activity with an ED50 of less than 1 microM against herpes simplex virus (HSV) types 1 and 2, varicella zoster virus, human cytomegalovirus (HCMV) and vaccinia in plaque reduction assays. Wild type HSV-2 and its thymidine kinase deficient variant are equally sensitive to (R,S)-HPMPG. (R,S)-HPMPG is 100-fold more potent than acyclovir (ED50 = 0.45 microM vs. 44 microM, respectively) against HCMV in cell culture, and 10-fold more active than acyclovir in extending survival time in mice intraperitoneally infected with 70 LD50 HSV-1. However, (R,S)-HPMPG is toxic when administered repeatedly at 44 mg/kg/day in uninfected adult mice. The diphosphoryl derivative of HPMPG was enzymatically synthesized and is a competitive inhibitor of HSV-1 DNA polymerase relative to dGTP (K1 = 0.03 microM). HPMPG-PP is 70-fold less active at inhibiting HeLa DNA polymerase alpha than HSV-1 DNA polymerase. At concentrations between 0.3 and 1.5 microM (R,S)-HPMPG inhibited HSV-1 DNA replication greater than or equal to 50% in infected cells as measured by nucleic acid hybridization. Consistent with inhibition of viral DNA synthesis, 6 to 30 microM (R,S)-HPMPG reduces late viral polypeptide synthesis in HSV-1 infected cells. These data indicate that (R,S)-HPMPG is a thymidine kinase independent broad spectrum antiviral drug which is capable of inhibiting viral DNA polymerase.

Optical and physical parameters of Plexiglas 55 and Lexan

The following parameters have been obtained for Plexiglas 55 and Lexan: refractive index n at 486.1 nm, 589.3 nm, and 656.3 nm, the thermooptic constant dn/dT at 632.8 nm, the linear thermal expansion coefficient; the photoelastic constants q(11), q(12), p(11), and p(12); and the elastic moduli c(11), c(12), s(11), and s(12). The experimental value for the density derivative of refractive index rho(dn/drho)T deviates by only a small amount from the value calculated from the Lorentz-Lorenz equation. This is the expected result for molecular solids. The density variation with temperature is the dominant contribution to dn/dT.

Chemically Modified Glucose Oxidase with Enhanced Hydrophobicity: Adsorption at Polystyrene, Silica, and Silica Coated by Lipid Monolayers

Covalent modification of glucose oxidase from Aspergillus niger by the palmitic acid ester of N-hydroxysuccinimide at a molar ratio ester:protein of 56:1 results in the formation of the enzyme derivative with 11 attached palmitic chains. Surface hydrophobicity measurements by a fluorescent probe, 8-anilino-1-naphthalenesulfonate, indicate a drastic increase in the hydrophobicity index of glucose oxidase after such a modification. The modified glucose oxidase displays a much higher adsorption affinity for hydrophilic (silica) as well as for hydrophobic (silica coated by phosphatidyl choline and cholesterol monolayers and polystyrene latex beads) surfaces, and forms more compact surface layers compared to the native glucose oxidase. Such a difference results from a spontaneous formation of micelle-like aggregates (clusters) of the hydrophobized enzyme molecules (average size 500 nm), which come into contact with a surface. A possible structure of the glucose oxidase surface layers and the nature of the forces determining the adsorption of the enzyme on various adsorbents are discussed. Copyright 1999 Academic Press.

Lipowitz metal shielding thickness for dose reduction of 6-20 MeV electrons

The relative dose reduction by Lipowitz metal of 6 to 20 MeV electrons from a Varian Associates Clinac-20 linear accelerator has been measured using a parallel plate thin wall ionization chamber. Metal thickness required for a 5% attenuation level for a 10 X 10 cm2 field are as follows: 6 MeV-2.3 mm, 9 MeV-4.4 mm, 12 MeV-8.5 mm, 16 MeV--18.0 mm, 20 MeV-25.0 mm.