Intravenous glutamine decreases lung and distal organ injury in an experimental model of abdominal sepsis

Introduction

The protective effect of glutamine, as a pharmacological agent against lung injury, has been reported in experimental sepsis; however, its efficacy at improving oxygenation and lung mechanics, attenuating diaphragm and distal organ injury has to be better elucidated. In the present study, we tested the hypothesis that a single early intravenous dose of glutamine was associated not only with the improvement of lung morpho-function, but also the reduction of the inflammatory process and epithelial cell apoptosis in kidney, liver, and intestine villi.

Methods

Seventy-two Wistar rats were randomly assigned into four groups. Sepsis was induced by cecal ligation and puncture surgery (CLP), while a sham operated group was used as control (C). One hour after surgery, C and CLP groups were further randomized into subgroups receiving intravenous saline (1 ml, SAL) or glutamine (0.75 g/kg, Gln). At 48 hours, animals were anesthetized, and the following parameters were measured: arterial oxygenation, pulmonary mechanics, and diaphragm, lung, kidney, liver, and small intestine villi histology. At 18 and 48 hours, Cytokine-Induced Neutrophil Chemoattractant (CINC)-1, interleukin (IL)-6 and 10 were quantified in bronchoalveolar and peritoneal lavage fluids (BALF and PLF, respectively).

Results

CLP induced: a) deterioration of lung mechanics and gas exchange; b) ultrastructural changes of lung parenchyma and diaphragm; and c) lung and distal organ epithelial cell apoptosis. Glutamine improved survival rate, oxygenation and lung mechanics, minimized pulmonary and diaphragmatic changes, attenuating lung and distal organ epithelial cell apoptosis. Glutamine increased IL-10 in peritoneal lavage fluid at 18 hours and bronchoalveolar lavage fluid at 48 hours, but decreased CINC-1 and IL-6 in BALF and PLF only at 18 hours.

Conclusions

In an experimental model of abdominal sepsis, a single intravenous dose of glutamine administered after sepsis induction may modulate the inflammatory process reducing not only the risk of lung injury, but also distal organ impairment. These results suggest that intravenous glutamine may be a potentially beneficial therapy for abdominal sepsis.     

Prediction of school-age IQ,academic achievement,and motor skills in children with positional plagiocephaly

IntroductionChildren with positional plagiocephaly and/or brachycephaly (PPB) are at risk of early developmental delay, but little is known about early life factors associated with school-age neurodevelopment. This study examined associations of demographic characteristics, prenatal risk factors and early neurodevelopment assessment with school-age IQ, academic performance, and motor development in children with PPB.MethodsThe study sample consisted of 235 school-age children with PPB followed since infancy. Outcome measures included IQ using the Differential Ability Scales-Second Edition, academic achievement as measured by the Wechsler Individualized Achievement Tests-Third Edition), and motor function using the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition. Linear regression was used to examine the incremental improvement of model fit of demographics, prenatal and early life characteristics, severity of PPB, and neurodevelopment at ages 7, 18, and 36 months as measured by the Bayley-3 on school-age scores.ResultsMean age at school-age assessment was 9.0 years. Adjusted r² for demographic, prenatal, and early life risk factors ranged from 0.10 to 0.22. Addition of PPB severity and Bayley-3 measures at ages 7 and 18 months did not meaningfully change model fit. Adjusted r² after inclusion of Bayley-3 at 36 months ranged from 0.35 to 0.41.ConclusionThis study suggests that PPB severity and very early life neurodevelopment have little association with school-age neurodevelopment above and beyond demographic and early life risk factors. However, preschool-age neurodevelopmental assessment may still be useful in identifying children with PPB at risk for delay and who may benefit from early intervention.     

Use of bone biochemical markers with dual-energy x-ray absorptiometry for early determination of bone loss in persons with spinal cord injury

Our cross-sectional study aimed at the early determination of changes in bone metabolism in terms of bone mineral density (BMD) and bone turnover in persons with complete spinal cord injury (SCI) during the acute phase of paraplegia. Combined dual-energy x-ray absorptiometry (DXA) and specific biochemical markers of bone turnover were used to determine bone metabolism. Seven persons with SCI (age, 31.3 +/- 9.5 years) who had sustained injury an average of 3 months earlier (103 +/- 10.8 days) were compared with 10 able-bodied controls (27.5 +/- 4.3 years). Four paraplegics and 3 quadriplegics composed the SCI group. BMD was measured by DXA, while bone turnover was evaluated by serum osteocalcin (OC), bone alkaline phosphatase (B-ALP), and serum and urinary type I collagen C-telopeptide (CTXs and CTXu). Regional BMD (proximal femur, lumbar spine, radius, lower limb) was similar in the 2 groups except in the upper limb (P <.05). CTXs and CTXu were significantly higher in SCI (P <.01 and P <.001, respectively), whereas among the bone formation markers used, only serum OC was affected by immobilization (P <.05). The SCI group developed hypercalciuria (0.76 +/- 0.37 v 0.35 +/- 0.14), whereas calcemia was normal (2.42 +/- 0.09 v 2.31 +/- 0.10). Intact parathyroid hormone (iPTH) and 1.25 (OH)(2) vitamin D levels were suppressed in persons with SCI (P <.001) by 80.6% and 66%, respectively. In conclusion, it was not possible to detect any variation in BMD from the DXA technique at this early stage of demineralization, but the sensitivity and early response of the biochemical markers strongly suggested their usefulness for the early identification of persons with SCI at risk of severe osteoporosis.     

Is snoring intensity responsible for the sleep partner’s poor quality of sleep?

Purpose

This study aimed to determine if the intensity of breathing noise (including snoring) and/or the presence of abnormal breathing events (ABE) are factors that trigger arousal/awakening of a snorer??s bed partner.

Methods

We conducted a prospective multicenter study investigating couples where the male had a chronic disturbing snoring. We simultaneously recorded the male??s respiration and snoring and the female?? sleep. We counted the number of arousals and awakenings during N2 sleep and randomly took nine of each. Then, for periods before, during, and after each arousal and awakening, we observed on the respiratory tracings what was happening in terms of breathing noise intensity and presence/absence of snoring and/or ABE.

Results

Thirteen couples were analyzed. The intensity of breathing noise and the presence/absence of snoring and/or ABE were comparable before and at initiation of arousal/awakening and between arousal and awakening. However, breathing volume intensity was lower and the presence of snoring and/or ABE was less frequent when the bed partner returned back to sleep from awakening compared to the other periods (p always <0.001).

Conclusions

The intensity of breathing noise or the presence of ABE does not seem to be essential to trigger an arousal or an awakening. However, the persistence of noise or events may prolong the duration of wakefulness during the sleep period and could be one factor that explains the bothersome snoring.     

Poikilocytic hereditary elliptocytosis associated with spectrin Alexandria: an alpha I/50b Kd variant that is caused by a single amino acid deletion

Hereditary elliptocytosis (HE) is a heterogeneous disorder of red blood cells frequently associated with abnormal limited tryptic digestion of the alpha I domain of spectrin and impaired spectrin dimer self- association. We studied two related individuals with poikilocytic hereditary elliptocytosis (HE) of different severity. Limited tryptic digestion of spectrin from these individuals showed the presence of a variant alpha I/50b Kd peptide at the expense of the normal alpha I/80 Kd peptide. Amino acid sequence analysis of the abnormal peptide showed that the proteolytic cleavage occurred after the arginine at position 470 of the alpha spectrin chain. Spectrin from these patients had an impaired ability to undergo self-association, as evidenced by increased amounts of spectrin dimers in 4 degrees C extracts of erythrocyte membrane from affected individuals. The polymerase chain reaction was used to study the DNA sequence of the alpha spectrin gene encoding the region of the alpha spectrin chain surrounding the abnormal proteolytic cleavage site. We detected the in-frame deletion of the trinucleotide CAT, encoding histidine 469, two amino acid residues to the N-terminal side of the abnormal proteolytic cleavage site between residues 470 and 471. Similar to many other defects of spectrin associated with HE, this deletion occurs in helix three of repeat 5 of the proposed triple helical model of spectrin repeats.     

Regulation of lymphangiogenesis in the diaphragm by macrophages and VEGFR-3 signaling

Lymphatic vessels play important roles in fluid drainage and in immune responses, as well as in pathological processes including cancer progression and inflammation. While the molecular regulation of the earliest lymphatic vessel differentiation and development has been investigated in much detail, less is known about the control and timing of lymphatic vessel maturation in different organs, which often occurs postnatally. We investigated the time course of lymphatic vessel development on the pleural side of the diaphragmatic muscle in mice, the so-called submesothelial initial diaphragmatic lymphatic plexus. We found that this lymphatic network develops largely after birth and that it can serve as a reliable and easily quantifiable model to study physiological lymphangiogenesis in vivo. Lymphangiogenic growth in this tissue was highly dependent on vascular endothelial growth factor receptor (VEGFR)-3 signaling, whereas VEGFR-1 and -2 signaling was dispensable. During diaphragm development, macrophages appeared first in a linearly arranged pattern, followed by ingrowth of lymphatic vessels along these patterned lines. Surprisingly, ablation of macrophages in colony-stimulating factor-1 receptor (Csf1r)-deficient mice and by treatment with a CSF-1R-blocking antibody did not inhibit the general lymphatic vessel development in the diaphragm but specifically promoted branch formation of lymphatic sprouts. In agreement with these findings, incubation of cultured lymphatic endothelial cells with conditioned medium from P7 diaphragmatic macrophages significantly reduced LEC sprouting. These results indicate that the postnatal diaphragm provides a suitable model for studies of physiological lymphangiogenic growth and maturation, and for the identification of modulators of lymphatic vessel growth.     

Development of autologous cytotoxic CD4+ T clones in a human model of B-cell non-Hodgkin follicular lymphoma

Immunotherapy for cancer aims to generate cytotoxic cells that are capable of eradicating tumour cells. It has been well demonstrated that helper, non-cytotoxic CD4(+) T cells are important for the induction and maintenance of anti-tumour immunity exerted by cytotoxic CD8(+) T cells. In contrast, the existence of direct anti-tumour, effector cytotoxic CD4(+) T cells remains elusive, mainly due to the paucity of reliable experimental data, especially in human B-cell non-Hodgkin lymphomas. This study developed an appropriate, autologous follicular B-cell non-Hodgkin follicular lymphoma model, including the in vitro establishment of a malignant, human leucocyte antigen class I (HLA-I) deficient B-cell line, and the generation of three autologous anti-tumour cytotoxic CD4(+) T-cell clones originating from the peripheral blood of the same patient. These three clones were considered as tumour specific, because they were capable of killing the malignant, HLA-I-deficient B-cell line through a classical HLA-II restricted perforin-mediated pathway, but did not lyse the Epstein-Barr virus-infected autologous normal B lymphocytes. All three CD4(+)clones were T-cell receptor Vbeta17-Dbeta1-Jbeta1.2 and exhibited an identical complementarity-determining region 3, suggesting the immunodominance of a single peptide antigen presented by tumour cells. Such lymphoma models would provide a useful tool for in vivo expansion and the adoptive transfer of selected CD4(+) cytotoxic cells in immunotherapeutic strategies.     

Drug-metabolizing enzyme expression in human normal, peritumoral and tumoral colorectal tissue samples

In the present study, we investigated Phase I (cytochrome P450; DT-diaphorase, DTD) and Phase II (epoxide hydrolase, EH; glutathione-S-transferases, GSTs) enzymes in normal colon from patients without colorectal adenocarcinoma and in peritumoral and tumoral tissues from patients with colorectal adenocarcinoma. No significant changes in levels of cytochrome P450IIIA4 (the only P450 detectable in this tissue), EH, GSTs and DTD activity were found between normal and peritumoral tissues. In tumoral tissue, compared with peritumoral tissues, we observed significant decreases in cytochrome P450IIIA4 (-50%, P less than 0.002) and EH (-60%, P less than 0.03), no change in DTD activity and significant increases in GST pi (+40%, P less than 0.03) and total GST activity (+30%, P less than 0.01). The numerous changes observed in tumoral tissues suggest that variations in drug-metabolizing enzyme expression in colorectal adenomatous polyps could represent pretumoral markers. Moreover, a better understanding of the expression of these enzymes in tumoral tissues would help us to choose the most appropriate colon tumor cell lines for the testing of new anti-cancer drugs.