Quantification of Left Ventricular Twisting Mechanics by Velocity Vector Imaging in an Animal Model of Pericardial Adhesions

Diagnosis of constrictive pericarditis remains clinically challenging. Untwisting of the left ventricle (LV) is essential for normal LV diastolic function. Echocardiography is able to measure LV twisting mechanics. We designed an animal model of constrictive pericarditis to determine how pericardial-epicardial adhesions impair LV twisting mechanics. In eight open-chest pigs, the heart was exposed while preserving the pericardium. We simulated early constrictive pericarditis by pericardial constriction and patchy adhesions induced with instant glue and pericardial-epicardial stitches. Using Velocity Vector Imaging™ (VVI), LV magnitudes of twisting and untwisting were measured along with hemodynamic data at baseline and after the experimental intervention. Significant decreases in end-diastolic volume, ejection fraction, stroke volume, and late diastolic filling velocity reflected the effects of the pericardial adhesions. Magnitude of LV untwisting rate decreased from –80 ± 23°/s to –26 ± 10 °/s (p = 0.0009). LV twisting rate dropped from 78 ± 20°/s to 40 ± 8°/s (p = 0.0039) and LV twist magnitude decreased from 9 ± 2° to 5 ± 2 ° (p = 0.0081). Patchy pericardial adhesions are associated with reductions in LV untwisting rate and twisting magnitude, consistent with a negative impact of constrictive pericarditis on systolic and diastolic function. Impairments in LV twisting mechanics may have a diagnostic role in the detection of early stages of constrictive pericarditis. (E-mail: belohlavek.marek@mayo.edu)     

Comparison of SPECT bone scintigraphy with MRI for diagnosis of meniscal tears

Background

Scintigraphy has been considered as competitive to MRI, but limited data are available on the accuracy of single photon emission tomography (SPECT) compared with MRI for the assessment of meniscal tears. Our objective was to assess the value of SPECT in comparison to MRI.

Methods

Between January 2003 and March 2004, sixteen patients were studied with both modalities and the accuracy rates of SPECT scan results, and MRI findings in the diagnosis of meniscal tears were compared. Arthroscopy was the gold standard.

Results

The respective sensitivity rate, specificity rate, and positive and negative predictive accuracies of MRI were 89%, 94%, 93%, and 79% and for SPECT those were 78%, 94%, 94%, and 88%. There was good agreement on the presence or absence of tears between two modalities (κ statistic = 0.699).

Conclusion

SPECT and MRI are both valuable imaging techniques. SPECT is a useful alternative when MRI is unavailable or unsuitable and it is beneficial when more possible accuracy is desired (such as when MRI results are either inconclusive or conflict with other clinical data).     

Increased prenatal blood manganese may induce gestational blood pressure

Objective: Pregnancy hypertension is the most common gestational complication and poses a critical risk for mother and fetus. Whether environmental factors may play an important role in disease occurrence is not fully determined. Methods: To investigate the effects of prenatal manganese (Mn) exposure on gestational blood pressure, 386 women were examined. Results: Early pregnancy blood Mn was significantly (p < 0.05) correlated with blood pressure through gestation. A significant association between odds of pre-hypertension with blood Mn was shown (OR:1.150, 95% CI:1.052–1.258). Conclusion: The current study results might suggest the blood Mn level during early stage of pregnancy as a potential risk factor for increasing the risk of gestational blood pressure.     

Vaccine-associated paralytic poliomyelitis in a patient with MHC class II deficiency.

Vaccine-associated paralytic poliomyelitis (VAPP) is a rare complication of oral polio vaccine. We describe a fatal case of VAPP in an 8-month-old boy with Major Histocompatibility Class II deficiency. The isolated poliovirus was a Sabin type 2-type 1 recombinant that showed 1.4% VP1 divergence from Sabin type 2.     

Artifactual changes in hematological variables in equine blood samples stored at different temperatures and various anticoagulants

The objective of this study was to determine the effect of storage time, temperature, and anticoagulant on hematologic parameters in equine blood samples. Blood samples were obtained from 50 clinically healthy warm-blooded horses at two major equestrian complexes in Tehran, Iran. The samples were collected in three different tubes containing EDTA, sodium citrate, or heparin and were analyzed within 4?h of collection. Blood samples collected into EDTA-containing tubes were stored at 4°C or 24°C. Each sample was analyzed again at 24, 48, and 72?h after collection. The statistically significant (P?<?0.05) alterations included decreased RBC count and increased hemoglobin concentration [Hgb] in blood samples stored at 24°C after 48 and 72?h; increased hematocrit in blood samples stored at 24°C after 24?h; decreased hematocrit in blood samples stored at 4°C after 72?h; decreased MCHC in blood samples stored at 4°C after 72?h; and decreased total WBC count in blood samples stored at 24°C after 48?h. Although there was no significant difference in hematologic analytes between heparinized and EDTA-anticoagulated blood samples, most of the hematologic analytes were decreased significantly (P?<?0.05) in sodium citrate-containing blood samples, compared with blood samples stored in EDTA. The results of this study suggest that within certain limitations for some hematologic analytes, equine blood samples stored in EDTA at 4°C for up to 72?h may be suitable for hematologic testing.     

Constructing a hybrid molecule with low capacity of IgE binding from Chenopodium album pollen allergens

Allergen specific immunotherapy is the only remedy to prevent the progression of allergic diseases. Nowadays, using of recombinant allergens with reduced IgE-binding capacity is an ideal tool for allergen immunotherapy. Therefore, in this study we focused on a hybrid molecule (HM) production with reduced IgE reactivity from Chenopodium album pollen allergens. By means of genetic engineering, a head to tail structure of the three allergens of the C. album pollen was designed. The resulting DNA construct coding for a 46kDa HM was inserted into an expression vector and expressed as hexahistidine tagged fusion protein in Escherichia coli. IgE reactivity of the HM was evaluated by western blotting, inhibition ELISA and in vivo skin prick test and its immunogenic property was tested by proliferation assay. The recombinant HM was expressed and purified by nickel-affinity chromatography. Comparison of the recombinant HM with a mixture of three recombinant allergens, as well as natural allergens in the whole C. album pollen extract via immunological experiments revealed that it has a much lower potential of IgE reactivity. Furthermore, in vivo skin prick tests showed that it has a significantly lower potency to induce cutaneous reactions than the mixture of recombinant wild type allergens and whole extract while, it had been preserved immunogenic properties. Our results have demonstrated that assembling three allergens of C. album in a hybrid molecule can reduce its IgE reactivity.     

<Emphasis Type="Italic">Iranian johnsongrass mosaic virus</Emphasis>: the complete genome sequence,molecular and biological characterization,and comparison of coat protein gene sequences

Iranian johnsongrass mosaic virus (IJMV) is one of the most prevalent viruses causing maize mosaic disease in Iran. An IJMV isolate, Maz-Bah, was obtained from the maize showing mosaic symptoms in Mazandaran, north of Iran. The complete genomic sequence of Maz-Bah is 9544 nucleotides, excluding the poly(A) tail. It contains one single open reading frame of 9165 nucleotides and encodes a large polyprotein of 3054 amino acids, flanked by a 5′-untranslated region (UTR) of 143 nucleotides and a 3′-UTR of 236 nucleotides. The entire genomic sequence of Maz-Bah isolate shares identities of 84.9 and 94.2 % with the IJMV (Shz) isolate, the lone complete genome sequence available in the GenBank at the nucleotide (nt) and deduced amino acid (aa) levels, respectively. The whole genome sequences share identities of 51.5–69.8 and 44.9–74.3 % with those of other Sugarcane mosaic virus (SCMV) subgroup potyviruses at nt and aa levels, respectively. In phylogenetic trees based on the multiple alignments of the entire nt and aa sequences, IJMV isolates formed a separate sublineage of the tree with potyviruses infecting monocotyledons of cereals, indicating that IJMV is a member of SCMV subgroup of potyviruses. IJMV is most closely related to Sorghum mosaic virus and Maize dwarf mosaic virus and less closely related to the Johnsongrass mosaic virus and Cocksfoot streak virus. To further investigate the genetic relationship of IJMV, 9 other isolates from different hosts were cloned and sequenced. The identity of IJMV CP nt and aa sequences of 11 Iranian isolates ranged from 86.4 to 99.8 % and 90.5 to 99.7 %, respectively, indicating a high nt variability in CP gene. Furthermore, in the CP-based phylogenetic tree, IJMV isolates were clustered together with a maize potyvirus described as Zea mosaic virus from Israel (with 86–89 % nt identity), indicating that both isolates probably are the strains of the same virus.     

Immunoregulation of Inflammatory and Inhibitory Cytokines by Vitamin D3 in Patients with Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD) is a group of idiopathic, chronic and relapsing inflammatory conditions of the gastrointestinal tract, caused by an aberrant and exaggerated immunological response in the gut. Supplementation of vitamin D3 in patients with IBD exerts both direct and indirect regulatory roles on the naïve T cells, thereby maintaining a balance between inflammatory and inhibitory cytokines. The direct actions of vitamin D3 on naïve T cells result in the proliferation of more regulatory T cells and inhibitory cytokines such as IL‐4, IL‐10 and IL‐5. The binding of vitamin D to dendritic cells (DCs) through vitamin D receptors inhibits the action of IL‐12 on DCs, resulting in the downregulation of Th1 and Th17. On the other hand, this interaction favours Th2 and Treg upregulation and facilitates the maintenance of immune homoeostasis between inflammatory and inhibitory cytokines which is essentially significant in the management of patients with IBD. The aim of this review was to explore the current and mounting scientific evidence on the roles of vitamin D3 in immunoregulation of inflammatory and inhibitory cytokines in patients with IBDs. An extensive literature search was conducted using keywords such as Vitamin D3*, IBD*, inflammatory cytokines*, inhibitory cytokines*, naïve‐T‐cells* and antigen presenting cells* through PubMed, SCOPUS and MEDLINE search engines. The results of the accumulated bodies of research that have been conducted demonstrate that vitamin D3 plays a major role not only in the immunoregulation of cytokines involved in the pathogenesis of IBDs but also in many other inflammatory disorders.