Does 3D orientation account for variation in osteon morphology assessed by 2D histology?

The primary microstructural unit of cortical bone, the secondary osteon or Haversian system, is widely assumed to have a cylindrical shape. It is generally accepted that osteons are roughly circular in cross-section and deviations from circularity have been attributed to deviations from longitudinal orientation. To our knowledge this idealized geometric relationship, which assumes osteons are perfect cylinders, has not been rigorously explored. As such, we sought to explore two research questions: (i) Does the orientation of osteons in 3D explain variation in shapes visualized in 2D? (ii) Can differences in osteon 3D orientation explain previously reported age-related differences observed in their 2D cross-sectional shape (e.g. more circular shape and decreased area with age)? To address these questions we utilized a combination of 2D histology to identify osteon shape and superimposed micro-computed tomography data to assess osteon orientation in 3D based upon the osteonal canal. Shape was assessed by the inverse of Aspect Ratio (On.AspR⁻¹, based on a fitted ellipse) – which ranged from 0 (infinitely elongated shape) to 1 (perfectly circular). A sample (n = 27) of human female anterior femoral cortical bone samples from across the human lifespan (20–87 years) were included in the analysis, which involved 1418 osteons. The overall mean measure of On.AspR⁻¹ was 0.703 (1.42 Aspect Ratio). Mean osteon orientation was 79.1° (90° being longitudinal). While we anticipated a positive relation between orientation and On.AspR⁻¹, we found the opposite – a weak negative correlation (with more oblique 3D osteon alignment, the 2D shape became more circular as reflected by increased On.AspR⁻¹). When analysis of covariance was performed with age and orientation as covariates, the negative relation with orientation was replaced by a significant relation with age alone. This relation with age accounted for 41% of the variation of On.AspR⁻¹. The results revealed that osteons, on average, are not circular in cross-section and that 3D orientation cannot account for deviation from circular shape. Osteons thus are strictly speaking not cylinders, as they tend to have elliptical cross-sections. We observed that osteons did become less elliptical in cross-section with age independent of orientation – suggesting this is a real change in morphology.     

Rh0(D) : Antigen Content of Human Spermatozoa*

¹³¹I-labelled anti-Rh₀ (D) antibody was made to react with suspensions of spermatozoa and red blood cells from Rh₀ (D) positive and negative donors at 37° for 1 hour. Spermatozoa from Rh₀ (D) positive donors did not take up more ¹³¹I anti-Rh₀ (D) than was bound by spermatozoa from Rh₀ (D) negative donors. The mean value for Rh₀ (D) positive donors was 0.0142±0.0061×10^-2 μg. nitrogen per 10⁶ spermatozoa, and the comparable value for Rh₀ (D) negative donors was 0.0189±0.0130×10^-2 μg. nitrogen per 10⁶ spermatozoa. Red blood cells from Rh₀ (D) positive donors took up thirty to forty times more ¹³¹I anti-Rh₀ (D) antibody than was taken up by spermatozoa from Rh₀ (D) positive donors, whereas red blood cells from Rh₀ (D) negative donors took up only 0.5 to 1.7 times more ¹³¹I anti-Rh₀ (D) antibody than was taken up by spermatozoa from Rh₀ (D) negative donors. Pre-treatment of spermatozoa with trypsin increased by two to three times the quantity of ¹³¹I anti-Rh₀ (D) antibody bound to spermatozoa from both Rh₀ (D) positive and negative donors. The quantitative increase was similar for spermatozoa from Rh₀ (D) positive and negative donors.

No evidence for the presence of Rh₀ (D) antigen on human spermatozoa was obtained using ¹³¹I anti-Rh₀ (D).

     

Comparative study of IgA VH3 gene usage in healthy TST− and TST+ population exposed to tuberculosis: deep sequencing analysis

The acquired immune response against tuberculosis is commonly associated with T-cell responses with little known about the role of B cells or antibodies. There have been suggestions that B cells and humoral immunity can modulate the immune response to Mycobacterium tuberculosis. However, the mechanisms involving B-cell responses in M. tuberculosis are not fully understood, in particular the antibody gene preferences. We hypothesized that a preferential use of V genes can be seen associated with resistance to infection mainly in the IgA isotype, which is of prominent importance for infection by pathogens via the mucosal route. We studied healthy individuals with long-term exposure to tuberculosis, infected (TST⁺) and uninfected TST⁻) with M. tuberculosis. From a total of 22 V genes analysed, the TST⁻ population preferred the V_H3-23 and Vκ1 genes. The V_H3-23 genes were subsequently subjected to 454 amplicon sequencing. The TST⁻ population showed a higher frequency of the D3-10 segment compared with the D3-22 segment for the TST⁺ population. The J segment usage pattern was similar for both populations with J4 segment being used the most. A preferential pairing of J4 segments to D3-3 was seen for the TST⁻ population. The antibodyome difference between both populations suggests a preference for antibodies with V_H3-23, D3-3, J_H4 gene usage by the TST⁻ population that could be associated with resistance to infection with M. tuberculosis.     

Specific overexpression of tumour necrosis factor‐α‐induced protein (TNFAIP)9 in CD14+CD16− monocytes in patients with rheumatoid arthritis: comparative analysis with TNFAIP3

The tumour necrosis factor (TNF)-α-induced proteins (TNFAIP)9 and TNFAIP3 play an important pathogenic role in murine arthritis. To clarify their pathophysiological roles in patients with rheumatoid arthritis (RA), we examined their expression and localization in peripheral blood mononuclear cells (PBMC). TNFAIP9 and TNFAIP3 mRNA expression was determined in PBMC of RA patients and healthy subjects (control). Flow cytometry was used to analyse the main TNFAIP9- and TNFAIP3-expressing cell populations. TNFAIP9 and TNFAIP3 mRNA expression levels were examined in vitro on CD14⁺ cells stimulated with TNF-α and lipopolysaccharide (LPS). The expression levels of TNFAIP9 and TNFAIP3 mRNA were also measured before and 12 weeks after treatment with tocilizumab and abatacept. TNFAIP9 expression was significantly higher, while TNFAIP3 expression was lower in PBMC of RA (n = 36) than the control (n = 24) (each P < 0·05). TNFAIP9 was expressed on CD14⁺ cells, especially in human leucocyte antigen D-related (HLA-DR)⁺CD14^brightCD16⁻cells, while TNFAIP3 was expressed mainly on CD3⁺ T cells. TNF-α and LPS induced TNFAIP9 and TNFAIP3 in human CD14⁺monocytes in vitro. Treatment with tocilizumab (n = 13), but not abatacept (n = 11), significantly reduced TNFAIP9 mRNA expression in PBMC, which was associated with reduction in the number of circulating CD14^bright monocytes. The expression of TNFAIP9 in CD14⁺ cells was specifically elevated in patients with RA, regulated by TNF-α and LPS, and suppressed by tocilizumab, while TNFAIP3 in PBMC showed different localization and induction patterns.     

Enhanced Toxicity for Mice of Combinations of Antibiotics with Escherichia coli Cells or Salmonella typhosa Endotoxin

Enhanced lethality for BALB/c mice has been observed after the administration of Salmonella typhosa endotoxin with either actinomycin D, cycloheximide, or nogalamycin. The dose of actinomycin D required to kill half of the mice (LD₅₀) was 0.8 mg/kg in normal animals, 0.35 mg/kg in mice administered 0.08 mg of endotoxin per kg, and 0.28 mg/kg in mice administered 0.2 mg of endotoxin per kg. The LD₅₀ of endotoxin in normal mice was 12 mg/kg and in mice given 0.4 mg of actinomycin D per kg was 0.067 mg/kg. The LD₅₀ of actinomycin D in mice administered 1.8 × 10⁸ live Escherichia coli cells per kg or 1.8 × 10⁹ heat-killed E. coli cells per kg was reduced to 0.4 mg/kg. The LD₅₀ of cycloheximide was 181 mg/kg in normal animals and 28 mg/kg in mice administered 4 mg of endotoxin per kg. The LD₅₀ of endotoxin in mice given 120 mg of cycloheximide per kg was 0.02 mg/kg. Enhanced lethality due to various combinations of cycloheximide and endotoxin was abolished by pretreatment of mice with endotoxin. The LD₅₀ of nogalamycin was 21 mg/kg in normal mice and 13 mg/kg in mice receiving 1 mg of endotoxin per kg.     

Bilobar colorectal liver metastases: a new model for preclinical studies

This study aimed to develop a new model of colorectal liver metastases (LM) in the rat. Both single macroscopic and multiple bilobar microscopic LM were investigated, as this closely resembled the human situation, before right hepatectomy was performed for ‘single’ right LM. The single macroscopic LM was elicited by direct injection of DHD/K12 colorectal cancer cells under the capsule of the median liver lobe in immunocompetent BDIX rats. The bilobar micrometastases were elicited by intraportal injection of DHD/K12 cells. A preliminary protocol was conducted to assess the dose of cells required to inject in to the portal vein, using 10⁶, 2 × 10⁶ and 3 × 10⁶ DHD/K12 cells (n = 15 rats). The resultant protocol for the experimental model used intraportal injection of 10⁶ DHD/K12 cells and direct injections of 0.5 × 10⁶, 10⁶ and 1.5 × 10⁶ DHD/K12 cells (n = 15 rats). For both protocols, BDIX rats were sacrificed at day 30 after injection. The preliminary protocol showed that intraportal injection of 10⁶ DHD/K12 cells was associated with bilobar micrometastases of 0.8 mm mean diameter at day 30. The main protocol assessed that direct injection of 0.5 × 10⁶ under the liver median lobe capsule and intraportal injection of 10⁶ DHD/K12 cells were associated at day 30 with a single macroscopic metastasis confined to a liver lobe and bilobar micrometastases, without peritoneal carcinomatosis or lung metastasis. Thus we have developed a new experimental model of bilobar colorectal LM including both macro- and microscopic colorectal LMs, which mimics the human situation and which will be useful in preclinical studies.     

Comparison between refraction measured by Spot Vision ScreeningTM and subjective clinical refractometry

OBJECTIVE:The purpose of this study was to evaluate the accuracy of Spot Vision Screening^TM as an autorefractor by comparing refraction measurements to subjective clinical refractometry results in children and adult patients.METHODS:One-hundred and thirty-four eyes of 134 patients were submitted to refractometry by Spot and clinical refractometry under cycloplegia. Patients, students, physicians, staff and children of staff from the Hospital das Clínicas (School of Medicine, University of São Paulo) aged 7-50 years without signs of ocular disease were examined. Only right-eye refraction data were analyzed. The findings were converted in magnitude vectors for analysis.RESULTS:The difference between Spot Vision Screening^TM and subjective clinical refractometry expressed in spherical equivalents was +0.66±0.56 diopters (D), +0.16±0.27 D for the vector projected on the 90 axis and +0.02±0.15 D for the oblique vector.CONCLUSIONS:Despite the statistical significance of the difference between the two methods, we consider the difference non-relevant in a clinical setting, supporting the use of Spot Vision Screening^TM as an ancillary method for estimating refraction.     

A genome-wide association study identifies PLCL2 and AP3D1-DOT1L-SF3A2 as new susceptibility loci for myocardial infarction in Japanese

Despite considerable progress in preventive and therapeutic strategies, myocardial infarction (MI) is one of the leading causes of death throughout the world. A total of 55 susceptibility genes have been identified mostly in European genome-wide association studies (GWAS). Nevertheless, large-scale GWAS from other population could possibly find additional susceptibility loci. To identify as many MI susceptibility loci as possible, we performed a large-scale genomic analysis in Japanese population. To identify MI susceptibility loci in Japanese, we conducted a GWAS using 1666 cases and 3198 controls using the Illumina Human610-Quad BeadChip and HumanHap550v3 Genotyping BeadChip. We performed replication studies using a total of 11 412 cases and 28 397 controls in the Japanese population. Our study identified two novel susceptibility loci for MI: PLCL2 on chromosome 3p24.3 (rs4618210:A>G, P=2.60 × 10⁻⁹, odds ratio (OR)=0.91) and AP3D1-DOT1L-SF3A2 on chromosome 19p13.3 (rs3803915:A>C, P=3.84 × 10⁻⁹, OR=0.89). Besides, a total of 14 previously reported MI susceptibility loci were replicated in our study. In particular, we validated a strong association on chromosome 12q24 (rs3782886:A>G: P=1.14 × 10⁻¹⁴, OR=1.46). Following pathway analysis using 265 genes related to MI or coronary artery disease, we found that these loci might be involved in the pathogenesis of MI via the promotion of atherosclerosis. In the present large-scale genomic analysis, we identified PLCL2 and AP3D1-DOT1L-SF3A2 as new susceptibility loci for MI in the Japanese population. Our findings will add novel findings for MI susceptibility loci.     

Killer cell immunoglobulin receptor profile on CD4+ CD28− T cells and their pathogenic role in non‐dialysis‐dependent and dialysis‐dependent chronic kidney disease patients

There is a progressive increase in cardiovascular disease with declining renal function, unexplained by traditional risk factors. A CD4⁺ T-cell subpopulation (CD4⁺ CD28⁻), activated by human heat-shock protein 60 (hHSP 60), expands in patients with acute coronary syndrome and is associated with vascular damage. These cells exhibit cytotoxicity via expression of activating killer cell-immunoglobulin-like receptor KIR2DS2, mainly in the absence of inhibitory KIR2DL3. We investigated expansion of these cells and the pathogenic role of the KIR in non-dialysis-dependent chronic kidney disease (NDD-CKD) and end-stage haemodialysis-dependent renal disease (HD-ESRD) patients. CD4⁺ CD28⁻ cells were present in 27% of the NDD-CKD and HD-ESRD patients (8–11% and 10–11% of CD4⁺ compartment, respectively). CD4⁺ CD28⁻ cells were phenotyped for KIR and DAP12 expression. Cytotoxicity was assessed by perforin and pro-inflammatory function by interferon-γ expression on CD4⁺ CD28⁻ clones (NDD-CKD n = 97, HD-ESRD n = 262). Thirty-four per cent of the CD4⁺ CD28⁻ cells from NDD-CKD expressed KIR2DS2 compared with 56% in HD-ESRD patients (P = 0·03). However, 20% of clones expressed KIR2DL3 in NDD-CKD compared with 7% in HD-ESRD patients (P = 0·004). DAP12 expression in CD28⁻ 2DS2⁺ clones was more prevalent in HD-ESRD than NDD-CKD (92% versus 60%; P < 0·001). Only 2DS2⁺ 2DL3⁻ DAP12⁺ clones were cytotoxic in response to hHSP 60. CD4⁺ CD28⁻ cells exhibited increased KIR2DS2, reduced KIR2DL3 and increased DAP12 expression in HD-ESRD compared with NDD-CKD patients. These findings suggest a gradual loss of expression, functionality and protective role of inhibitory KIR2DL3 as well as increased cytotoxic potential of CD4⁺ C28⁻ cells with progressive renal impairment. Clonal expansion of these T cells may contribute to heightened cardiovascular events in HD-ESRD.     

Unmasking Myocardial Dysfunction in Patients Hospitalized for Community-Acquired Pneumonia Using a 4-Chamber 3-Dimensional Volume/Strain Analysis

Lower respiratory infection was reported as the most common fatal infectious disease. Community-acquired pneumonia (CAP) and myocardial injury are associated; yet, true prevalence of myocardial injury is probably underestimated. We assessed the rate and severity of myocardial dysfunction in patients with CAP. Admitted patients diagnosed with CAP were prospectively recruited. All the patients had C-reactive protein (CRP), brain natriuretic peptide (BNP), and high-sensitivity cardiac troponin (hs-cTnl) tests added to their routine workup. 2D/3D Doppler echocardiography was done on a Siemens Acuson SC2000 machine ≤ 24 h of diagnosis. 3D datasets were blindly analyzed for 4-chamber volumes/strains using EchobuildR 3D-Volume Analysis prototype software, v3.0 2019, Siemens-Medical Solutions. Volume/strain parameters were correlated with admission clinical and laboratory findings. The cohort included 34 patients, median age 60 years (95% CI 55–72). The cohort included 18 (53%) patients had hypertension, 9 (25%) had diabetes mellitus, 7 (21%) were smokers, 7 (21%) had previous myocardial infarction, 4 (12%) had chronic renal failure, and 1 (3%) was on hemodialysis treatment. 2D/Doppler echocardiography findings showed normal ventricular size/function (LVEF 63 ± 9%), mild LV hypertrophy (104 ± 36 g/m²), and LA enlargement (41 ± 6 mm). 3D volumes/strains suggested bi-atrial and right ventricular dysfunction (global longitudinal strain RVGLS =  − 8 ± 4%). Left ventricular strain was normal (LVGLS =  − 18 ± 5%) and correlated with BNP (r = 0.40, p = 0.024). The patients with LVGLS >  − 17% had higher admission blood pressure and lower SaO₂ (144 ± 33 vs. 121 ± 20, systolic, mmHg, p = 0.02, and 89 ± 4 vs. 94 ± 4%, p = 0.006, respectively). hs-cTnl and CRP were not different. Using novel 3D volume/strain software in CAP patients, we demonstrated diffuse global myocardial dysfunction involving several chambers. The patients with worse LV GLS had lower SaO₂ and higher blood pressure at presentation. LV GLS correlated with maximal BNP level and did not correlate with inflammation or myocardial damage markers.     

Down-regulation of TET2 in CD3+ and CD34+ cells of myelodysplastic syndromes and enhances CD34+ cells proliferation

Aims and background: To investigate the expressions of TET2 mRNA in bone marrow CD3⁺ and CD34⁺ cells of the patients with myelodysplastic syndromes (MDS) and to study the effect of silencing TET2 by small interfering RNA (siRNA) on the biological characteristics of CD34⁺ cells. Methods: CD3⁺ and CD34⁺ cells were sorted by magnetic activated cell-sorting system from bone marrow of MDS patients and controls. The mRNA expressions of TET2 in bone marrow CD3⁺ and CD34⁺ cells of 28 MDS patients and 20 controls were detected by qPCR. The silencing effect of RNA interference (RNAi) on TET2 expression in CD34⁺ bone marrow cells of normal control was identified by qPCR and Western blot analysis. The cell cycle kinetics and cell apoptosis were then detected by flow cytometry. Results: The expression of TET2 mRNA in CD3⁺ and CD34⁺ cells was down-regulated in MDS compared with that in controls [(0.16±0.11) vs. (1.05±0.32) (P<0.001); (0.58±0.26) vs. (1.25±0.94) (P<0.005)]. The siRNA targeting TET2 suppressed the expression of TET2 in normal CD34⁺ cells. Meanwhile, the proliferation activity was significantly enhanced [G0/G1: (87.82±8.25)% vs. (92.65±7.06)% and (93.60±5.54)%, P<0.05; S: (11.50±8.31)% vs. (6.92±7.04)% and (5.95±5.53)%, P<0.05] and the apoptosis rate was declined [(21.28±9.73)% vs. (26.17±9.88)% and (26.20±9.78)%] in the cells which transfected with TET2 siRNA as compared to those in the cells transfected with scrambled siRNA and control cells. Conclusions: The TET2 expression of in CD3⁺ and CD34⁺ cells of MDS patients was decreased. Suppression of TET2 expression renders the CD34⁺ cells harboring more aggressive phenotype. This preliminary finding suggests that CD34⁺ cells lowering expression of TET2 may play an oncogenic role on myeloid tumor and CD3⁺ T cells of MDS patients may be derived from the malignant clone.     

Behavior of soluble human 125I-labeled C3b,the third component of complement,after binding to human cells

The behavior of ¹²⁵I-labeled C3b incubated with two C3b receptor-positive cells (human erythrocytes and the B lymphoblastoid Raji line), one C3b receptor-negative cell (T lymphoblastoid CEM line) and solubilized membranes from each cell was analyzed by sucrose density gradient (SDG) and sodium dodecyl sulfate polyacrylamide gel electrophoresis. Whichever whole cell was tested, the unbound ¹²⁵I-labeled C3b recovered in the cell supernatant was not cleaved. When ¹²⁵I-labeled C3b was bound to whole cells or incubated with solubilized membranes, three different activities were detected: (a) nonspecific C3b polymerization, induced on the membrane of C3b receptor-positive or C3b receptor-negative cells; (b) specific C3b receptor activity solubilized only from the membrane of the two C3b receptor-positive cells and (c) C3b hydrolytic activity, inhibited by 5 x 10^?4 M phenyl methyl sulfonyl fluoride, only extracted from human erythrocyte membranes and carried by a molecule different from that of C3b receptor. C3b receptor activity solubilized from Raji and human erythrocyte membranes was detected by a 12 S peak complex formation on a 10-30 % SDG and characterized by an affinity constant of 2 x 10⁷ to 4 x 10⁷ mol^?1. Hydrolysis of labeled C3b (M_r = 175 000) by solubilized human erythrocyte membranes led to the formation of a split product of M_r = 35 000 consisting of two disulfide-linked polypeptide chains of M_r = 17 000. This is the first report of a breakdown of C3b on cell membranes different from the physiological breakdown described in the fluid phase.     

Anti-HLA-E mAb 3D12 mimics MEM-E/02 in binding to HLA-B and HLA-C alleles: Web-tools validate the immunogenic epitopes of HLA-E recognized by the antibodies

HLA-E shares several peptide sequences with HLA-class Ia molecules. Therefore, anti-HLA-E antibodies that recognize the shared sequences may bind to HLA-class Ia alleles. This hypothesis was validated with a murine anti-HLA-E monoclonal antibody (mAb) MEM-E/02, which reacted with microbeads coated with several HLA-B and HLA-C antigens. In this report, the hypothesis was reexamined with another mAb 3D12, considered to be specific for HLA-E. The antibody binding is evaluated by measuring mean fluorescence index [MFI] with Luminex Multiplex Flow-Cytometric technology. The peptide-inhibition experiments are carried out with synthetic shared peptides, most prevalent to HLA-E and HLA-Ia alleles. The results showed that mAb 3D12 simulated MEM-E/02 in recognizing several HLA-B and HLA-C antigens. Both 3D12 and MEM-E/02 did not bind to HLA-A, HLA-F and HLA-G molecules. As observed with MEM-E/02, binding of 3D12 to HLA-E is inhibited by the peptides sequences ¹¹⁵QFAYDGKDY¹²³ and ¹³⁷DTAAQI¹⁴². Decrease in binding of mAb 3D12 to HLA class Ia, after heat treatment of antigen coated microbeads, supports the contention that the epitope may be located at the outside of the “thermodynamically stable” α-helix conformations of HLA-E. Several sequence and structure-based web-tools were employed to validate the discontinuous epitopes recognized by the mAbs. The scores obtained by these web-tools distinguished the shared peptide sequences that inhibited the mAb binding to HLA-E. Furthermore, ElliPro web tool points out that both mAbs recognize the conformational discontinuous epitopes (the shared inhibitory peptide sequences) in the secondary structure of the HLA-E molecule. The study favors the contention that the domain of the shared inhibitory peptide sequences may be the most immunogenic site of HLA-E molecule. It also postulates and clarifies that amino acid substitution on or near the binding domains may account for the lack of cross reactivity of 3D12 and MEM-E/02 with HLA-A, HLA-F and HLA-G molecules.     

A Splice Variant of GNB3 and Peripheral Polyneuropathy in Type 1 Diabetes

Abnormalities in G protein-mediated signal transduction could be involved in the pathogenesis of diabetic polyneuropathy (DPN). Here we test whether the GNB3 C825T variant confers susceptibility to DPN in type 1 diabetes (T1D) mellitus. The C825T marker of GNB3 was genotyped in genomic DNA from blood isolated from a total of 213 Russian T1D patients 100 of whom had DPN. Compared to carriers of the wild-type genotype C/C, diabetic subjects with genotypes T/T had significantly increased risk to develop DPN (Odds Ratio (OR) of 4.4 (p = 0.001). The adjustment for confounders (age, sex, body mass index, cigarette smoking, and level of reduced glutathione) resulted in increase of the OR value up to 4.72 (p = 8.9 × 10^-3). The further adjustment for hypertension abolished the association between the GNB3 C825T variant and DPN (OR = 1.95, p = 0.18). Non-complicated subjects homozygous for T/T showed decreased levels of reduced glutathione (T/T: 69 ± 19 vs. C/T: 74 ± 19 vs. C/C: 77 ± 17 μmol/l, p = 0.009). Compared to other GNB3 variants, carriers of the T/T genotype had elevated systolic blood pressure (SBP) in complicated (T/T: 115.8 ± 9.1 vs. C/T: 113.3 ± 8.2 vs. C/C: 109.5 ± 8.7 mm/Hg, p = 0.036) and non-complicated T1D patients (T/T: 118.1 ± 8.4 vs. C/T: 116.9 ± 7.9 vs. C/C: 112.1 ± 7.2 mm/Hg, p = 0.02). However, the significance of association between the C825T polymorphism was lost after adjustment for confounding risk factors. In conclusion, the 825T allele of GNB3 is likely to accelerate the development of DPN through primary effects to SBP and hypertension in subgroups of diabetic patients with impaired neurovascular function and advanced oxidative stress.     

Sweat Rates, Sweat Sodium Concentrations, and Sodium Losses in 3 Groups of Professional Football Players

Context:

Sweat sodium losses have never been reported in a large cohort of American football players.

Objective:

To compare sweat rates (SwtRs), sweat sodium concentrations (SwtNa⁺), and sodium losses in 3 groups of players (backs and receivers [BK], linebackers and quarterbacks [LB/QB], and linemen [LM]) to determine if positional differences and, therefore, size differences exist.

Design:

Observational study.

Setting:

Data were collected during practices in the second week of 2 consecutive training camps. The wet bulb globe temperature was 78.5°F ± 3.5°F (25.9°C ± 1.9°C).

Patients or Other Participants:

Eighteen BK, 12 LB/QB, and 14 LM volunteered.

Intervention(s):

Sterile sweat patches were applied to the right forearm after the skin was appropriately cleaned. The patches were removed during practice, placed in sterile tubes, centrifuged, frozen, and later analyzed by flame photometry.

Main Outcome Measure(s):

Sweat rate, SwtNa⁺, and sodium loss. We calculated SwtR by change in mass adjusted for urine produced and fluids consumed divided by practice time in hours.

Results:

Other than age, physical characteristics were different among groups (P < .001). The SwtR was different among groups (F_2,41  =  7.3, P  =  .002). It was lower in BK (1.42 ± 0.45 L/h) than in LB/QB (1.98 ± 0.49 L/h) (P < .05) and LM (2.16 ± 0.75 L/h) (P < .01), but we found no differences between SwtRs for LB/QB and LM. The SwtNa⁺ was not different among groups (BK  =  50 ± 16 mEq/L, LB/QB  =  48.2 ± 23 mEq/L, and LM  =  52.8 ± 25 mEq/L) and ranged from 15 to 99 mEq/L. Sweat sodium losses ranged from 642 mg/h to 6.7 g/h, and findings for group comparisons approached significance (P  =  .06). On days when players practiced 4.5 hours, calculated sodium losses ranged from 2.3 to 30 g/d.

Conclusions:

The BK sweated at lower rates than did the midsized LB/QB and large LM, but LB/QB sweated similarly to LM. Sweat sodium concentration and daily sodium losses ranged considerably. Heavy, salty sweaters require increased dietary consumption of sodium during preseason.     

Placental phenotype and resource allocation to fetal growth are modified by the timing and degree of hypoxia during mouse pregnancy

AbstractThe placenta adapts its transport capacity to nutritional cues developmentally, although relatively little is known about placental transport phenotype in response to hypoxia, a major cause of fetal growth restriction. The present study determined the effects of both moderate hypoxia (13% inspired O₂) between days (D)11 and D16 or D14 and D19 of pregnancy and severe hypoxia (10% inspired O₂) from D14 to D19 on placental morphology, transport capacity and fetal growth on D16 and D19 (term∼D20.5), relative to normoxic mice in 21% O₂. Placental morphology adapted beneficially to 13% O₂; fetal capillary volume increased at both ages, exchange area increased at D16 and exchange barrier thickness reduced at D19. Exposure to 13% O₂ had no effect on placental nutrient transport on D16 but increased placental uptake and clearance of ³H‐methyl‐d‐glucose at D19. By contrast, 10% O₂ impaired fetal vascularity, increased barrier thickness and reduced placental ¹⁴C‐methylaminoisobutyric acid clearance at D19. Consequently, fetal growth was only marginally affected in 13% O₂ (unchanged at D16 and −5% at D19) but was severely restricted in 10% O₂ (−21% at D19). The hypoxia‐induced changes in placental phenotype were accompanied by altered placental insulin‐like growth factor (IGF)‐2 expression and insulin/IGF signalling, as well as by maternal hypophagia depending on the timing and severity of the hypoxia. Overall, the present study shows that the mouse placenta can integrate signals of oxygen and nutrient availability, possibly through the insulin‐IGF pathway, to adapt its phenotype and optimize maternal resource allocation to fetal growth during late pregnancy. It also suggests that there is a threshold between 13% and 10% inspired O₂ at which these adaptations no longer occur.     

Cooperative action of CD8 T lymphocytes and natural killer cells controls tumour growth under conditions of restricted T‐cell receptor diversity

In mice expressing a transgenic T-cell receptor (TCR; TCRP1A) of DBA/2 origin with reactivity towards a cancer-germline antigen P1A, the number of TCRP1A CD8⁺ T cells in lymphoid organs is lower in DBA/2 than in B10.D2 or B10.D2(× DBA/2)F₁ mice. This reduction results from haemopoietic cell autonomous differences in the differentiation of the major histocompatibility complex class I-restricted TCRP1A thymocytes controlled by DBA/2 versus B10.D2-encoded genes. We report here that the lower number of TCRP1A CD8⁺ T cells in DBA/2 mice correlated with their poor resistance to P1A-expressing mastocytoma solid tumours. Functional potency of CD8⁺ cytolytic T lymphocytes (CTL) from the above strains was not compromised, but their number after expansion appeared to be influenced by their genetic background. Intriguingly, non-transgenic DBA/2 mice resisted P1A⁺ tumours more efficiently despite poor representation of P1A-specific CTL. This was partly the result of their more heterogeneous TCR repertoire, including reactivity to non-P1A tumour antigens because mice that had rejected a P1A⁺ tumour became resistant to a P1A⁻ variant of the tumour. Such ‘cross-resistance’ did not develop in the TCRP1A transgenic mice. Nonetheless, reconstitution of RAGº^/º mice with TCRP1A CD8⁺ T cells, with or without CD4⁺ T cells, or exclusive representation of TCRP1A CD8⁺ T cells in RAGº^/º TCRP1A transgenic mice efficiently resisted the growth of P1A-expressing tumours. Natural killer cells present at a higher number in RAGº^/º mice also contributed to tumour resistance, in part through an NKG2D-dependent mechanism. Hence, in the absence of a polyclonal T-cell repertoire, precursor frequencies of natural killer cells and tumour-specific CTL affect tumour resistance.     

Effect of vitamin D3 supplementation on Staphylococcus aureus nasal carriage: a randomized,double-blind,placebo-controlled trial in healthy adults

Observational studies have reported an inverse association between serum 25-hydroxyvitamin D (25OHD) concentrations and Staphylococcus aureus nasal carriage; however, clinical trials of vitamin D supplementation are lacking. To assess the effect of vitamin D3 supplementation on persistent S. aureus nasal carriage we conducted a randomized, double-blind, placebo-controlled trial among 322 healthy adults. Participants were given an oral dose of either 200 000 IU vitamin D3 for each of 2 months, followed by 100 000 IU monthly or placebo in an identical dosing regimen, for a total of 18 months. Nasal swabs for S. aureus culture and serum for 25OHD measurement were obtained at baseline, 6, 12 and 18 months of study. The mean baseline concentration of 25OHD was 72 nM (SD 22 nM). Vitamin D3 supplementation increased 25OHD levels which were maintained at >120 nM throughout the study. Nasal colonization by S. aureus was found in 31% of participants at baseline. Persistent carriage, defined as those that had positive S. aureus nasal cultures for all post-baseline swabs, occurred in 20% of the participants but vitamin D3 supplementation was not associated with a reduction in persistent carriage (OR = 1.39, 95% CI 0.63–3.06). Risk factor analysis showed that only gender was significantly associated with carriage, where women were less likely to be carriers than men (relative risk 0.83, 95% CI 0.54–0.99). Serum 25OHD concentrations were not associated with the risk of carriage. In conclusion, monthly administration of 100 000 IU of vitamin D3 did not reduce persistent S. aureus nasal carriage.     

NLRP3 inflammasome is essential for the development of chronic obstructive pulmonary disease

Background: Chronic obstructive pulmonary disease (COPD) is now recognized as an inflammatory disease and the nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasome was speculated to participate into its pathophysiological process, however, a direct role of NLRP3 has yet to be clearly shown. Method: COPD model was established by tobacco inhalation, COPD modeling and NLRP3 knockout mice were treated with similar dose and duration of tobacco inhalation for 12 months, the lung function, lung damage and immune responses were evaluated between control, wild type COPD and NLRP3 knock out C57B1/6 mice. Results: 10 months after tobacco inhalation, the respiratory system resistance indexes of COPD mice was significantly higher than that of control and NLRP3 knockout mice (2.8 ± 0.5 vs. 1.2 ± 0.3 and 1.3 ± 0.1 cm H₂O ml^-1 s^-1, P < 0.05); the respiratory system compliance indexes of COPD was significantly lower than that of control and NLRP3 knockout mice (0.31 ± 0.02 vs. 0.43 ± 0.04, and 0.39 ± 0.01 ml/cm H₂O); the NLRP3 knockout mice displayed no distinguishable pathological damage in the lung. Of the broncho-alveolar lavage fluid (BALF), the concentration of IL-1 and IL-18 of the COPD were significantly higher than that of control and NLRP3 knockout mice (IL-1: 286.8 ± 1.7 vs. 23.8 ± 2.1 and 24.2 ± 1.3 pg/mL, P < 0.05; IL-18: 104.5 ± 4.2 vs. 12.6 ± 2.1 and 15.7 ± 2.8 pg/mL, P < 0.05); the total numbers of macrophages, eosinophils, lymphocyte and neutrophil of control, COPD and NLRP3 knockout mice were 2.3 ± 0.4, 0.5 ± 0.2, 10.3 ± 3.4 and 2.8 ± 2.7; 8.7 ± 1.1, 12.5 ± 1.1, 45.3 ± 3.3 and 29.2 ± 4.2; and 3.2 ± 0.7, 1.8 ± 0.4, 18.1 ± 1.1 and 12.8 ± 3.4 × 10⁴ mL, respectively; the rates of NLRP3 positive macrophages in the BALF of control, COPD and NLRP3 knockout mice were 5.0 ± 1.0%, 78.1 ± 9.2% and 2.0 ± 0.9%, respectively. Conclusion: NLRP3 inflammasome is essential for the development of COPD and blockade of NLRP3 might be a possible therapeutic strategy for COPD.     

Polymeric chiral crown ethers, 7. Synthesis of polymers incorporating methyl glycosides of α-D-altrose, α-D-galactose, α-D-glucose and α-D-mannose residues via copolymerization of divinyl ethers

Polymers with chiral asymmetric crown ether units ( 5, 6, 7 and 8 ) were synthesized via cationic cyclopolymerization of methyl 2,3-bis{O-[2-(2-vinyloxyethoxy)ethyl]}-4,6-O-benzylidene α-D -altro-, α-D -galacto-, α-D -gluco- and α-D -manhopyranosides ( 1, 2, 3 and 4 ), respectively. The enantioselective transport of the methyl ester of phenylglycine (PhGlyOCH₃) and phenylalanine (PhAlaOCH₃) was examined through a bulk chloroform solution of chiral polymers from one aqueous solution to another. The transport rate of PhAlaOCH₃ was larger than that of PhGlyOCH₃ for every host polymer. For polymer 7 , the optical purity of PhAlaOCH₃ transported from one to the other phase was 12,6%, and the ratio of rate constants for the faster moving enantiomer A and the slower moving enantiomer B (k_A^*/k_B^*) was 1,48. The faster moving enantiomer was the L -isomer except for the systems polymer 7 ? PhAlaOCH₃ and polymer 8 ? PhAlaOCH₃. This enantioselectivity is caused by the diastereotopic faces of the crown ether units in the host polymers.