To form or not to form a reaction complex: exploring ion-molecule reactions between C3H4 isomers and Xe+ and O2.

Ion-molecule reactions are an essential contributor to the chemistry of a diverse range of environments. While a great deal of work has been done to understand the fundamental mechanisms driving these reactions, there is still much more to discover. Here, we expand upon prior studies on ion-molecule reactions involving two isomers of C3H4, allene (H2C3H2) and propyne (H3C3H). Specifically, we probe the previously observed isomeric dependent reactivity of these molecules by reacting them with two ions with nearly identical ionization potentials, Xe+ and O2+. Our goal is to determine if the isomer-dependent reaction mechanisms previously observed are universal for C3H4 or if they depend on the ion character as well. Through the combination of experimental measurements and theoretical calculations, we found that both isomeric structure and identity of the ion contribute to the propensity of a reaction complex forming or for only long-range charge transfer to occur.

Assessment of systemic and pulmonary arterial remodelling in women with systemic sclerosis.

OBJECTIVES: Systemic sclerosis (SSc) leads to pulmonary circulation dysfunctionand there are some indications of systemic circulation impairment. We evaluated the influence of SSc on the elastic properties of large systemic arterial walls and potential correlations between systemic and pulmonary circulation involvement. METHOD: We examined 75 consecutive women (mean age 53.13±10.1 years) with confirmed SSc [mean disease duration (DD) 7.1±9.1 years] and 21 age-matched female volunteers (mean age 52.6±8.3 years, ns). Pulse wave velocity (PWV) and transthoracic echocardiography were performed. SSc patients were divided into two groups according to the median of DD: ≤3 years (39 patients) and >3 years (36 patients). RESULTS: Patients with DD>3 years had higher PWV than those with DD≤3 years and controls (log PWV: 2.23±0.23 vs. 2.13±0.16 and vs. 2.11±0.16 m/s; p=0.028 and 0.029, respectively). In addition, echocardiographic indices showed impaired right ventricular (RV) function in the patients with DD>3 years. Also in these SSc patients, PWV correlated with clinical and echocardiographic parameters of pulmonary circulation: age (r=0.64, p<0.0001), acceleration time of pulmonary ejection (AcT; r=-0.38, p=0.021), and tricuspid regurgitation peak gradient (TRPG; r=0.34, p=0.04). Multiple linear regression analysis showed that PWV was independently associated with DD (ß=0.22, p==0.02), AcT (ß=-0.215, p=0.03), and age (ß=0.44, p<0.001). CONCLUSIONS: In patients with SSc lasting more than 3 years, the disease is characterized by increased stiffness of the large systemic arteries. Longer duration of SSc leads simultaneously to the increased stiffness of the large systemic arteries and to the progressive impairment of RV function and its coupling to the pulmonary arterial bed.

Oral Lactobacilli and salivary acidic proline-rich proteins (APRP-1/2) in dental caries.

A previous study shows that levels of acidic salivary proline-rich phosphoproteins-1/2 (APRP-1/2) increase with caries severity. The aim of this study was to examine whether this relationship also depends on the presence of H2O2-producing strains of Lactobacillus spp. Adults with severe caries (decayed, missing, and filled teeth (DMFT) > 13.9, n = 28) were compared with similarly aged adults who had minimal caries (DMFT < 5, n = 20). A total of 48 samples of whole unstimulated saliva were collected in the morning and centrifuged. Lactobacillus spp. were isolated from the sediment in Rogosa agar and peroxide (H2O2) production was determined by growing the isolates on TMB-Plus agar. Salivary APRP-1/2 content in the saliva supernatant was estimated using an enzyme-linked immunosorbent sandwich assay (ELISA). Lactobacilli were present in 67% of both caries groups but were H2O2 positive only in the minimal caries group. Irrespective of the presence of Lactobacilli, the total content of APRP-1/2 proteins was 34.5 ± 4.9 ng/ml in severe caries but just under half this in minimal caries. We conclude that Lactobacillus spp. was absent from about a third of the severe and minimal caries groups, and H2O2-producing strains were present only in the minimal caries group. The severe caries group possessed twice the content of salivary APRP 1/2 proteins as the minimal caries group. The implications of these findings for caries development are discussed.

The immunohistochemistry and ultrastructure of ganglioglioma with chromosomal alterations: a case report.

Ganglioglioma, together with its counterparts-ganglioneuroma and gangliocytoma are relatively uncommon neoplasms of the brain composed of neoplastic neurons (ganglion and ganglioid cells) and glial cells. We report here a case of ganglioglioma studied by electron microscopy. The case was further characterized by peculiar chromosomal alterations, 46,XX[6]/43,XX[1], der(1)t(1;5)(q21;q12), der(8;13)(q10;q10),-9,i(10)(q10). Routine light microscopy revealed mixed neuro-glial tumor composed of pilocytic astrocytes with abundant Rosenthal fibers and relatively numerous ganglion cells. The latter were immunoreactive with antibodies (Abs) against synaptophysin and neurofilament protein (NFP). Anti-NFP Abs also immunostained numerous distorted axons embedded in the tumor mass. Some of these showed bullous swellings and thus were analogous to dystrophic neurites or spheroids. Ganglion cells were characterized by abundant intracytoplasmic dense-core vesicles, absence of intermediate filaments and numerous microtubules. Occasionally a close apposition of ganglion cells and Rosenthal fibers were seen. Dense-cored vesicles were pleomorphic and ranged in diameter from small synaptic vesicles to large lysosome-like neurosecretory granules. The former occasionally formed characteristic dumbbell shapes. Neoplastic astrocytes were identical to those of other glial tumors of astrocytic lineage; numerous Rosenthal fibers were frequently seen.

[The level of Interleukin-6 in patients with amyotrophic lateral sclerosis]. / Poziom interleukiny--6 u chorych ze stwardnieniem zanikowym bocznym.

The role of immune factors in the pathogenesis of ALS is taken into account and, in view of this, it was decided to study the role of interleukins (IL) taking IL-6 as an example. Its concentration was determined in blood and CSF with Amersham RIA kits. The study was carried out on 16 ALS patients and 16 patients with low back pain who served as controls. The IL-6 level in blood and CSF did not vary between these groups statistically significantly. Then from the ALS group the cases with only bulbar symptoms or with predominance of bulbar symptoms were isolated. This subgroup comprised 6 patients, their mean age was higher, and disease duration was shorter. The IL-6 level in the CSF was 27.1 +/- 8.6 nmol/ml and was statistically significantly higher than in the remaining cases. The specificity of this finding is discussed.

CTA for screening of complicated atherosclerotic carotid plaque--American Heart Association type VI lesions as defined by MRI.

BACKGROUND AND PURPOSE: High-resolution carotid MR imaging can accurately identify complicated American Heart Association lesion type VI plaques, which are characterized by thrombus, hemorrhage, or a ruptured fibrous cap. The purpose of this study is to evaluate whether CTA can be used as screening tool to predict the presence or absence of American Heart Association lesion type VI plaques as defined by high-resolution MR imaging. METHODS: Fifty-one patients with suspected ischemic stroke or TIA with carotid CTA and carotid MR imaging performed within 14 days of the event/admission from April 2008 to December 2010 were reviewed. Vessels with stents or occlusion were excluded (n = 2). Each carotid artery was assigned an American Heart Association lesion type classification by MR imaging. The maximum wall thickness, maximum soft plaque component thickness, maximum calcified component thickness, and its attenuation (if the soft plaque component thickness was >2 mm) were obtained from the CTA. RESULTS: The maximum soft plaque component thickness proved the best discriminating factor to predict a complicated plaque by MR imaging, with a receiver operating characteristic area under the curve of 0.89. The optimal sensitivity and specificity for detection of complicated plaque by MR imaging was achieved with a soft plaque component thickness threshold of 4.4 mm (sensitivity, 0.65; specificity, 0.94; positive predictive value, 0.75; and negative predictive value, 0.9). No complicated plaque had a soft tissue plaque thickness <2.2 mm (negative predictive value, 1) and no simple (noncomplicated) plaque had a thickness >5.6 mm (positive predictive value, 1). CONCLUSIONS: Maximum soft plaque component thickness as measured by carotid CTA is a reliable indicator of a complicated plaque, with a threshold of 2.2 mm representing little to no probability of a complicated American Heart Association lesion type VI plaque.