The chemokine CXCL3 is responsible for the constitutive chemotactic activity of bovine milk for neutrophils

Bovine milk is known to exert a potent chemotactic activity on neutrophils, but the responsible agent has not been identified. The objective of the study was to characterize the main biochemical component responsible for this chemotactic activity. A neutrophil shape change assay was used to locate active milk fractions separated by chromatography. A single protein was isolated and identified by amino acid sequencing and mass spectrometry as CXCL3. Recombinant bovine chemokines and specific antibodies were used to show that normal milk contains active concentrations of CXCL1 (1-5ng/ml) and CXCL3 (100-500ng/ml), whereas CXCL2 and CXCL8/IL-8 were not detected. Depletion experiments with antibodies showed that CXCL3 was the main chemotaxin for neutrophils in normal (non-mastitic) milk. The chemokine CXCL3 was located by immunohistochemistry in mammary epithelial cells, and abundant mRNA was found in uninflamed mammary tissue, suggesting constitutive secretion by the lactating mammary epithelium. These results indicate that CXCL3/GRO-gamma is the major chemotactic factor for neutrophils in bovine milk in the absence of inflammation, and that it is secreted constitutively in milk by mammary epithelial cells. This finding prompts the question of the biological significance of permanent high concentrations of a CXC chemokine in milk.     

Effects of localized intraspinal injections of a noradrenergic blocker on locomotion of high decerebrate cats

Previous studies demonstrated that neuronal networks located in midlumbar segments (L3-L4) are critical for the expression of locomotion in cats following complete spinalization. In the present study the importance of several thoracolumbar segments (T8-L7) for the generation of spontaneous hindlimb locomotion in decerebrate cats was evaluated. Experiments were performed in high decerebrate cats (n = 18) walking spontaneously. Yohimbine, an alpha2-noradrenergic antagonist, was microinjected intraspinally in various thoracolumbar segments. Locomotor performance was evaluated with kinematics and electromyographic (EMG) recordings before and after each injection. When and if spontaneous locomotion (SL) was abolished, skin or perineal stimuli (exteroceptive stimuli) were used to trigger locomotion (exteroceptive-induced locomotion [EL]). Yohimbine injections at L3 or L4 completely inhibited SL and EL. In contrast, injections at T8 did not interfere with SL or EL. Injections at T10, T11, T12, L5, L6, and L7 inhibited SL but EL could still be evoked. Injections at T13, L1, and L2 had similar effects except that the quality of locomotion evoked by exteroceptive stimulation declined. Combined injections at T13, L1, and L2 abolished SL and EL, in contrast to injections restricted to the same individual segments. Simultaneous injections at L5, L6, and L7 also abolished SL but EL could still be induced. These results suggest that noradrenergic mechanisms in L3-L4 segments are involved in the expression of locomotion in decerebrate cats, whereas antagonizing noradrenergic inputs in individual rostral or caudal segments may alter the expression and overall quality of the locomotor pattern without abolishing locomotion.     

Early human herpesvirus type 6 reactivation after allogeneic stem cell transplantation: a large-scale clinical study

This study investigated the impact of human herpesvirus type 6 (HHV6) reactivation within 100 days of allogeneic stem cell transplantation (allo-SCT) on patient outcomes. HHV6 plasma loads were monitored weekly by quantitative PCR. Of 235 consecutive patients, 112 (48%) had an early positive HHV6 PCR test (group A) and 123 (52%) did not (group B). HHV6 reactivation was less frequent in patients who received reduced-intensity conditioning (P = .028). In group A, only 6 patients (5%) were asymptomatic; the most common clinical manifestations were fever (n = 60), skin rash (n = 57), diarrhea (n = 51), pulmonary complications (n = 19), and neurologic disorders (n = 12). Compared with the patients in group B, those in group A experienced delayed platelet engraftment (P = .003) and more frequent grade II-IV acute graft-versus-host disease (GVHD) (47% versus 30% in group B; P = .009). In multivariate analysis, the most important factors influencing the development of grade II-IV acute GVHD development were early HHV6 reactivation (P = .03) and unrelated donor status (P < .001). HHV6 reactivation adversely influenced 6-month survival (P = .04). Of?the 38 evaluable patients receiving antiviral treatment, 34 had a significantly decreased HHV6 load. Our findings indicate that HHV6 reactivation after allo-SCT is associated with delayed platelet engraftment, early posttransplantation mortality, and the development of acute GVHD. Careful monitoring of HHV6 by PCR is warranted during the early posttransplantation period.     

Sex differences on emotional processing are modulated by subclinical levels of alexithymia and depression: a preliminary assessment using event-related potentials

Several studies have suggested that women are more sensitive than men to emotions in general. Event-related potential (ERP) studies have demonstrated N2 and P3b modulations, suggesting that women allocate more attentional resources to emotions than men do. However, the exact origin of this emotional modulation by sex is still a matter of debate. We wondered whether these sex differences might be due to some specific personality traits of women and men. Thirty participants (15 males and 15 females) were selected so that there were no sex differences on alexithymia, or depression and anxiety scales. The participants were asked to complete a "modified emotional" oddball task, in which they had to detect deviant stimuli among frequent neutral ones as quickly as possible. Behavioral performance, N2 and P3b ERP data were analyzed. When personality factors were controlled for, the sex differences on N2 and P3b components of the ERPs disappeared. Moreover, linear regression analyses showed that alexithymia was much better than sex at predicting the N2 latencies, while depression was the best factor for predicting the P3b latency. These results suggest that personality factors should be taken into account when sex differences on emotional processing are investigated.     

Electromyographic investigation of unstable patella before and after its realignment operation

Background:

Patellar dislocations are either due to superolateral contracture of the soft tissue or imbalance of the power between the vastus medialis (VM) and the vastus lateralis (VL). The imbalance of muscle power as an etiology of patellar dislocation has not been studied. Hence, we studied the recurrent, habitual and permanent dislocations of the patella with an electromyogram (EMG) of the vastus medialis, vastus lateralis, and pes anserinus, before and after realignment operations, to document the muscle imbalance and effectiveness of the realignment operation.

Materials and Methods:

An electromyographic investigation was carried out on the vastus medialis and vastus lateralis in nine recurrent, 20 habitual, and 13 permanent dislocations of the patella, before and after their realignment operations. Pes anserinus transposition, which acted as a medial stabilizer of the patella, was also investigated with an EMG study, to understand its role on patellar stability at 0°, 30°, 60°, 90°, 120°, 150°, and full flexion of the knee. The age of the patients varied from nine to 30 (mean 15) years. There were 24 males and 18 females. Twenty-six patellar dislocations were on the right and 16 were on the left side.

Results:

Electromyographic pictures reveal subnormal activity of the vastus medialis in all types of dislocations and similar activities of the vastus lateralis in permanent and habitual dislocations recorded pre operatively, which recovered to almost normal values postoperatively, at the mean one-year follow-up. Pes anserinus, which was used for medial stabilization of the patella after its realignment, maintained normal EMG activity before and after the operation.

Conclusion:

This study is significant for understanding the imbalance of muscle activities in patients with an unstable patella, which can be rectified without recurrence after pes anserinus transposition.     

Tear film,contact lenses and tear biomarkers

This article summarises research undertaken since 1993 in the Willcox laboratory at the University of New South Wales, Sydney on the tear film, its interactions with contact lenses, and the use of tears as a source of biomarkers for ocular and non‐ocular diseases. The proteome, lipidome and glycome of tears all contribute to important aspects of the tear film, including its structure, its ability to defend the ocular surface against microbes and to help heal ocular surface injuries. The tear film interacts with contact lenses in vivo and interactions between tears and lenses can affect the biocompatibility of lenses, and may be important in mediating discomfort responses during lens wear. Suggestions are made for follow‐up research.     

Low baseline and subsequent higher aortic abdominal aneurysm FDG uptake are associated with poor sac shrinkage post endovascular repair

Purpose

The growth phases of medically treated abdominal aortic aneurysms (AAA) are frequently associated with an ¹⁸F–fluorodesoxyglucose positron emission tomography (FDG-PET) pattern involving low baseline and subsequent higher FDG uptake. However, the FDG-PET patterns associated with the endovascular aneurysm repair (EVAR) of larger AAA are presently unknown. This study aimed to investigate the relationship between serial AAA FDG uptake measurements, obtained before EVAR and 1 and 6 months post-intervention and subsequent sac shrinkage at 6 months, a well-recognized indicator of successful repair.

Methods

Thirty-three AAA patients referred for EVAR (maximal diameter: 55.4?±?6.0 mm, total volume: 205.7?±?63.0 mL) underwent FDG-PET/computed tomography (CT) before EVAR and at 1 and 6 months thereafter, with the monitoring of AAA volume and of a maximal standardized FDG uptake [SUVmax] averaged between the axial slices encompassing the AAA.

Results

Sac shrinkage was highly variable and could be stratified into three terciles: a first tercile in which shrinkage was absent or very limited (0–29 mL) and a third tercile with pronounced shrinkage (56–165 mL). SUVmax values were relatively low at baseline in the 1st tercile (SUVmax: 1.69?±?0.33), but markedly increased at 6 months (2.42?±?0.69, p?=?0.02 vs. baseline). These SUV max values were by contrast much higher at baseline in the 3rd tercile (SUVmax: 2.53?±?0.83 p?=?0.009 vs. 1st tercile) and stable at 6 months (2.49?±?0.80), while intermediate results were documented in the 2nd tercile. Lastly, the amount of sac shrinkage, expressed in absolute values or in percentages of baseline AAA volumes, was positively correlated with baseline SUVmax (p?=?0.001 for both).

Conclusion

A low pre-EVAR FDG uptake and increased AAA FDG uptake at 6 months are associated with reduced sac shrinkage. This sequential FDG-PET pattern is similar to that already shown to accompany growth phases of medically treated AAA.

     

Effects of procaine on the oxidative phosphorylation of brain mitochondria from senescent rats

Senescence affects cerebral metabolic functions. Various drugs have been tested to counteract the effects of aging on the brain. In this paper, we studied the influence of treatment using procaine, 1 mg per 100 g body weight, injected over a period of 3 days, to both young and old rats, on the phosphorylative oxidation properties of cerebral mitochondria. Respiratory activity decreased significantly in the brain of old rats. This reduction of oxygen consumption measured in the presence of glutamate, reached 31% in state 4, 25% in state 3 and, in the presence of succinate, 23% in state 4 without significant changes in state 3. The injection of procaine into young rats induced a significant increase of oxygen consumption rate with both glutamate and succinate as substrates. The same treatment administered to old rats was followed by a rise in respiratory activity, with values close to those observed in young control rats. Although the mechanism of action of procaine is not yet clear, there is some evidence that it interacts with membrane phospholipid sites. Therefore, it may be concluded that procaine facilitates oxygen transport towards the mitochondrial matrix by modifying the membrane structure in both old and young rats, although, in the latter case, this increase is not intended to improve the energetic properties of the mitochondrion.