New phenotypic, functional and electrophysiological characteristics of KG-1 cells

Myeloid dendritic cells (DC) are representatives of a rare and phenotypically diverse population of professional antigen presenting cells possessing high functional heterogeneity and flexibility. Here we studied the phenotypic, functional and electrophysiological characteristics of KG-1 cells, an erythroleukemia model cell line, which shares morphological and physiological similarities with immature and mature myeloid DC. We compared the expression of internalizing receptors and other cell surface molecules, antigen uptake and migration of unstimulated and activated KG-1 cells with the characteristics of immature and mature DC. Unstimulated KG-1 cells were less potent in capturing extracellular materials than immature DC. In contrast to monocyte-derived DC KG-1 cells stimulated by PMA and ionomycin ceased to migrate along the MIP-3beta chemokine gradient despite their high expression of CCR7 chemokine receptor and MDR, a transporter implicated in DC migration. Moreover, we determined the ion channel repertoire of KG-1 cells before and after treatment with PMA and ionomycin by using the patch-clamp technique. We found that both unstimulated and activated KG-1 cells expressed time- and voltage-independent, ChTx sensitive intracellular Ca(2+)-gated potassium conductance suggesting the presence of K(Ca) channels in their membranes. Based on our results we propose that KG-1 cells resemble myeloid DC but also possess unique phenotypic, functional and electrophysiological characteristics.     

Degradation Kinetics of BMP 777, an Elastase Inhibitor

Purpose. The objective was to evaluate the degradation profile of the elastase inhibitor DMP 777 and lay the foundation for formulation development. Methods. The pK_a was determined by potentiometric titration in mixed-aqueous solvents. The degradation kinetics were studied as a function of pH, buffer concentration, ionic strength, methanol concentration and temperature using a stability-indicating HPLC assay. The degradation products were identified by LC-MS, NMR, and by comparison with authentic samples. Results. The pK_a for the protonated piperazine nitrogen was estimated to be 7.04. The pH-rate profile is described by specific acid-, water-, and specific base-catalyzed pathways. The pH of maximum stability is in the range of 4 to 4.5 where water is the principal catalyst in the reaction. Buffer catalysis, primary salt effects and medium effects were observed. The proposed mechanism for acid catalyzed degradation is the rarely observed A_AL1 which involves alkyl-nitrogen heterolysis. The driving force for the reaction appears to lie in the stability of the benzylic carbocation. The proposed mechanism for base catalyzed degradation is B_AC2 which involves -lactam ring opening. The -lactam ring of DMP 777, a monolactam, appears to be as reactive as that in benzylpenicillin in the k _OH controlled region where a similar mechanism of hydrolysis should be operative. A contributing factor to this increased reactivity may lie in the reduced basicity of the -lactam nitrogen making it a good leaving group. Conclusions. The degradation profile indicates that development of a solution dosage form of DMP 777 with adequate shelf-life stability at room temperature is feasible.     

RECALLED PARENTAL REARING STYLE AND DIMENSIONS OF HYPNOTIC RESPONSE

So far, only a few studies have investigated how memories of parental rearing style are associated with hypnotic response, and these were either qualitative or confined to the behavioral aspect of hypnotizability. The present study aims to employ standardized, quantitative measures to investigate the associations between recalled parental rearing style and the behavioral, phenomenological, and emotional dimensions of hypnotic response. Two samples of healthy adult subjects (N = 438) completed a questionnaire on their parents’ behavior and participated in a standard group hypnosis session in which their hypnotizability score, hypnotic experiences, and archaic involvement were assessed. Memories of cold and punishing parental behavior were associated with negative experiences related to the hypnotic state and negative emotions toward the hypnotist. The authors conclude that assessing parental behavior may be important in planning hypnotherapeutic interventions.     

Diffusion abnormalities of the corpus callosum in patients receiving bevacizumab for malignant brain tumors: suspected treatment toxicity

Bevacizumab has been reported to cause diffusion restriction in the tumor bed of patients with malignant gliomas. This study evaluated prolonged diffusion restriction, in the corpus callosum (CC), of patients with malignant brain tumors treated with bevacizumab. We retrospectively reviewed our database of patients treated with bevacizumab for malignant brain tumors looking for those with restricted diffusion in the CC. CC ADC ratio measurements were obtained prior to and following treatment. Correlation was made with biopsy (n = 3) and MR perfusion (n = 7) and PET (n = 4). The temporal evolution of these changes relative to therapy was examined with mixed effects regression analysis. Nine patients (eight malignant gliomas, one malignant meningioma) out of 146 patients were found to have developed areas of diffusion restriction in the CC. These areas tended to enlarge and coalesce over serial MRIs and persisted for up to 22 months. Hypoperfusion was demonstrated in MR perfusion in 7/7. PET was hypometabolic in all 4. Biopsy of the CC showed no tumor in 3/3. ADC ratio measurements indicated a significant overall effect of time (F(16,60) = 11.2; p < 0.0001), consistent with persistent diffusion restriction over the measured time periods. Bevacizumab causes prolonged diffusion restriction in the CC. The negative MR perfusion, FDG PET and histopathology suggest this is a toxicity of bevacizumab and not active tumor. Awareness of these changes can assist in patient care.     

Corneal Manifestations of Systemic Sclerosis

Purpose: Corneal involvement in systemic sclerosis (SSc) is rare, but due to rich collagen composition cornea is especially vulnerable to connective tissue diseases. Therefore, our aim was to evaluate corneal parameters of SSc patients.

Methods: The study included 32 SSc patients and 39 control subjects with no ocular symptoms or ocular surface disorders. All study participants underwent Pentacam evaluation and objective signs of dry eye disease (DED), and clinical parameters were evaluated.

Results: All pachymetric values, most of the corneal front surface, corneal volume, as well as anterior chamber depth measurements were significantly lower in the SSc group than in the control group (p < 0.05). Significant negative correlation was found between corneal parameters and age on the one hand, and disease duration on the other.

Conclusions: Early recognition of corneal impairment, a possible extraintestinal manifestation of SSc, should be included in the check-up of the disease in order to reduce sight-threatening complications.     

Isolation of microsatellite markers from tiger grouper (Mycteroperca tigris) and characterization in yellowfin grouper (Mycteroperca venenosa), coney (Cephalopholis fulva), and red hind (Epinephelus guttatus)

Thirty-six microsatellite markers were isolated from an enriched genomic library of tiger grouper (Mycteroperca tigris) and characterized in 20 individuals each for yellowfin grouper (Mycteroperca venenosa), coney (Cephalopholis fulva), and red hind (Epinephelus guttatus). The microsatellites include 23 dinucleotide repeats, twelve trinucleotide repeats, and one tetranucleotide repeat. The microsatellites characterized in this study will be useful for further evaluation of population-genetic indices in the economically important subfamily Epinephelinae.