CT-based sarcopenia and outcomes in patients undergoing VATS anatomical resection for NSCLC

Objective

Sarcopenia is defined by a progressive loss of skeletal muscle mass and strength, combined with muscle fatty infiltration. Lung cancer patients frequently suffer from sarcopenia which may be associated with poorer post-operative outcomes. The aim of this study is to evaluate whether preoperative CT-based sarcopenia was associated with postoperative outcomes and survival after VATS resections in patients with early-stage non-small cell lung cancer (NSCLC).

Methods

We retrospectively reviewed all consecutive patients that underwent anatomical resection for NSCLC between 2012 and 2019. The skeletal muscle index (SMI) and muscle quality (SMRA and IMAT) were measured at the L3 vertebral level on preoperative CT or PET/CT scans. We used the following SMI cut-off values for sarcopenia: 52.4 cm2 /m2 for men and 38.5 cm2 /m2 for women.

Results

In total, 401 patients (sex ratio F/M: 173/228, mean age: 67 +/- 9.3 years) underwent VATS lobectomies (n=304) and segmentectomies (n=97) for NSCLC. Overall morbidity and mortality were 42.4% and 0.2%, respectively. The median length of stay was 7 days (IQR: 4–10). Sarcopenia was identified in 92 patients (23%). Patients with sarcopenia were predominantly males (75% vs 25%, p<0.001) and had lower BMI (21.4 vs 26.5, p<0.001). Patients with sarcopenia presented significantly increased morbidity (53.2% vs 39.2%, p=0.017) and had longer lengths of stay (6 vs 8 days, p=0.032). However, only lower BMI and ASA score >2 remained associated with increased morbidity on multivariate analysis. The median overall survival was comparable between patients with sarcopenia and those without sarcopenia (41 vs. 46 months, p=0.240).

Conclusion

Based on CT assessment alone, preoperative sarcopenia appeared to have little impact on postoperative clinical outcomes or overall survival in patients undergoing VATS pulmonary resection. Further studies should also consider muscle strength and physical performance, in addition to CT imaging, for preoperative risk assessment.

Local control and short-term outcomes after VATS segmentectomy vs lobectomy for pT1c pN0 NSCLC (2–3 cm)

Objective

Pulmonary segmentectomy has shown comparable oncological results to lobectomy for non-small cell lung cancers (NSCLC) of less than 2 cm. However, controversy remains for tumors of larger size. The aim of this study was to compare short-term outcomes and local control in pT1c pN0 NSCLC that were intentionally treated by VATS segmentectomy or lobectomy.

Methods

Multicenter retrospective study from January 2014 to October 2021 of 162 consecutive patients undergoing complete (R0) anatomical resections for pT1c pN0 NSCLC. Two groups, VATS lobectomy (VL) or VATS segmentectomy (VS) were defined according to the extension of the resection. Patients’ characteristics, postoperative outcomes and survival were compared.

Results

In total, 162 patients underwent VL (n=81) or VS (n=81). Except for age (median of 68 vs 71 years, p=0.034) and past medical history of cancer (32% vs 48%, p=0.038), there was no difference between VL and VS in terms of demographics and comorbidities (table1). Segmentectomies were performed in upper lobes in 68% and single segments represented 46% of all cases. Conversion thoracotomy rate was 5% in both groups. Morbidity were similar in both groups (34% vs 30%, p=0.5). The median time for chest tube removal (3 vs 2 days, p=0.002) and median LOS (6 vs 5 days, p=0.039) were in favor of the VS group. Significantly larger tumor (25 mm vs 23.5 mm p=0.001) and an increased number of lymph nodes removal (median 14 vs 10, p<0.001) were found in the VL group. During the follow-up (median: 31 months), no statistical difference was found for local and distant recurrence in VL groups (12.3%) and VS group (6.2%) (p=0.414). Overall survival was comparable in-between both groups (p=0.166).

Conclusion

Despite a short follow-up, our preliminary data shows that local control is comparable for VATS lobectomy and VATS segmentectomy. Further prospective randomized trials are needed to corroborate these results.

Is faster better? Impact of operative time on postoperative outcomes after VATS anatomical pulmonary resection

Objective

Video-Assisted Thoracic Surgery (VATS) is now the preferred approach for standard anatomical pulmonary resections. However, operative time (OT) for this technique is correlated to many aspects, such as the surgical complexity or the surgeon’s experience and skills. The aim of this study was to identify the factors associated with prolonged OTs and to assess the impact of OT on the development of post-operative complications after VATS anatomical pulmonary resections.

Methods

Retrospective monocentric study including all consecutive patients undergoing a VATS anatomical pulmonary resection for benign or malignant lesions between January 2010 and December 2019. Postoperative outcomes were compared between short (<150 minutes) and long (≥150 minutes) OTs. A multivariate analysis was carried out to identify predictors of longer OTs and post-operative complications.

Results

A total of 836 patients underwent a VATS anatomical pulmonary resection for malignant (n = 767, 91.7%) or benign (n = 69, 8.3%) lesions. Lobectomies were performed in 555 (66.4%), segmentectomies in 250 (29.9%), sleeve lobectomies in 16 (1.9%), bilobectomies in 11 (1.3%) and pneumonectomy in 4 (0.5%) patients. The conversion rate to thoracotomy was 7.7%. Of those 836 patients, 495 (59.2%) were operated within 150 minutes. During the 30-postoperative day period, the overall morbidity was significantly lower in the short OT group (29.1% vs. 40.5%; p = 0.001). Both the duration of drainage (3 vs. 4 days; p < 0.00001) and the length of hospital stay (6 vs. 7 days; p < 0.00001) were significantly reduced in the short OT group. Two predictors of long OT were identified on multivariate analysis: male sex (OR 1.41, p = 0.04) and neoadjuvant chemotherapy (OR 3.46, p = 0.003). A long OT was identified as an individual predictor of postoperative complications (OR 1.84, p < 0.0001).

Conclusion

A prolonged OT is an individual risk factor for postoperative complications in patients undergoing VATS anatomical pulmonary resection.

Outcomes of multi-gestational pregnancies affected by esophageal atresia - tracheoesophageal fistula

BACKGROUND

Contemporary outcomes of infants with esophageal atresia with or without tracheoesophageal fistula (EA/TEF) from multi-gestational pregnancies compared to those of singleton pregnancies have not been reported.

METHODS

A single-center retrospective review of EA/TEF patients born from 1999 to 2013 was performed. Patient demographics, gestational age (GA), birth weight, associated anomalies, requirement for gastrostomy tube and mortality were reviewed.

RESULTS

Singleton EA/TEF patients outnumbered those from multi-gestational pregnancies nearly 10:1 (214 vs 22 patients). EA/TEF patients from multi-gestational pregnancies were more likely to be premature (77% vs. 32%), have lower birth weight (mean 1766 g vs. 2695 g), have associated duodenal atresia (18% vs. 6%) and require gastrostomy tube (41% vs. 33%) for feeding challenges compared to EA/TEF singletons. Mortality was also significantly greater for multi-gestational EA/TEF patients compared to singleton EA/TEF patients (18% vs. 6%).

CONCLUSION

EA/TEF infants from multi-gestational pregnancies have greater clinical complexity and mortality than singleton EA/TEF patients. Parents of EA/TEF multi-gestational infants should be appropriately counseled and supported.

Painful Tooth Stimulation Elevates Matrix Metalloproteinase-8 Levels Locally in Human Gingival Crevicular Fluid

Recent studies have demonstrated that pulpal pain can induce neurogenic inflammatory reactions in gingiva and the expression of pro-inflammatory neuropeptides in gingival crevicular fluid (GCF). Neuropeptides co-ordinate the activity of immuno-effector cells and may influence the secretion of matrix metalloproteinase (MMP)-8, the major tissue-destructive protease in GCF. With this background, we studied whether experimental pulpal pain can trigger changes in GCF MMP-8 levels. The molecular forms of MMP-8 in the GCF of stimulated and non-stimulated teeth were analyzed by Western immunoblot, and MMP-8 levels by quantitative immunofluorometric assay. Painful stimulation of the upper incisor provoked significant elevations in GCF MMP-8 levels of the stimulated tooth. Western immunoblot revealed elevations in both neutrophil- and mesenchymal-type MMP-8 isoforms. At the same time, the GCF MMP-8 levels of the non-stimulated teeth were not changed. Analysis of these data indicated that pulpal pain can induce local elevations in MMP-8 levels in GCF.

Tracking wind-dispersed seeds using (15)N-isotope enrichment

Seed dispersal influences a wide range of ecological processes. However, measuring dispersal patterns, particularly long-distance dispersal, has been a difficult task. Marking bird-dispersed seeds with stable (15)N isotopes has been shown to be a user-friendly method to trace seed dispersal. In this study, we determined whether (15)N urea solution could be used to enrich seeds of two common wind-dispersed plants, Eupatorium glaucescens (Asteraceae) and Sericocarpus tortifolius (Asteraceae). We further tested if the water type (distilled versus tap) in (15)N urea solutions influences the level and variability of enrichment of plant seeds, and if increasing spraying frequency per se increases enrichment. Because droughts may lower seed set or kill plants, we wanted to investigate if the additional use of an externally applied anti-transpirant affects the intake of externally applied (15)N into seeds. The results demonstrate that (15)N enrichment of seeds can facilitate dispersal experiments with wind-dispersed plants. The use of distilled water in (15)N urea solutions did not increase (15)N enrichment compared to tap water. Further, enrichment was more efficient at lower spray frequencies. Both the use of tap water and low frequencies could lower time, effort and project costs. The results suggest that species can be protected from drought using an anti-transpirant without decreasing the incorporation of (15)N into seeds.

Zoledronate and pamidronate depress neutrophil functions and survival in mice

BACKGROUND AND PURPOSE

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been identified as a severe complication of patients previously treated with i.v. bisphosphonates. It has been noted that necrotic bone from BRONJ sites display signs of bacterial infection suggesting that an immune defect may play a role in the pathophysiology of BRONJ. Here, we have examined the effect of two potent bisphosphonates, zoledronate and pamidronate, on neutrophil function, differentiation and survival.

EXPERIMENTAL APPROACH

The effect of bisphosphonates on chemotaxis, NADPH oxidase activity and neutrophil survival were assessed in vitro using bone marrow-derived primary neutrophils or in vitro differentiated haematopoetic progenitors from mice. The same parameters and the number of circulating neutrophils were quantified in neutrophils isolated from mice treated in vivo with zoledronate. In vivo recruitment of neutrophils was assessed by sodium periodate-induced peritonitis.

KEY RESULTS

Zoledronate and pamidronate inhibited in vitro neutrophil chemotaxis and NADPH oxidase activity in a dose-dependent manner. In vivo recruitment of neutrophils was also suppressed. Zoledronate did not affect in vitro differentiation of neutrophils but shortened their life span in a granulocyte-colony stimulating factor-dependent manner. fMLP-induced activation of RhoA activity was decreased by zoledronate treatment.

CONCLUSIONS AND IMPLICATIONS

Our results show that bisphosphonate exposure leads to impaired neutrophil chemotaxis, neutrophil NADPH oxidase activity and reduced circulating neutrophil counts. This work suggests that bisphosphonates have the potential to depress the innate immune system for a prolonged time, possibly contributing to the pathogenesis of BRONJ.

[Calciphylaxis. A less well-known, clinically relevant disease]

Calciphylaxis is a rare disease which has been increasingly reported in recent decades and has consequently shifted into the focus of clinical and scientific research. The clinical picture is characterized by extensive ischemic ulcerations of the skin and subcutis. Histologically, the small vessels in these lesions show prominent calcifications. Due to the extensive areas of ulceration and necrosis as well as frequently present comorbidities, patients with calciphylaxis are prone to infection and sepsis. In this work, we describe the case of a female kidney-transplant patient with vasculitis who, despite good graft function, developed a fulminant calciphylaxis of both thighs 4 years post transplantation and died of septic complications. The differential diagnoses as well as clinical procedures are described in detail in the case history. In the discussion, we give an overview of the current state of knowledge regarding the etiopathogenesis, risk factors, diagnostic measures and clinical management of calciphylaxis.

Postural and dynamic masseter and anterior temporalis muscle EMG repeatability in serial assessments

Electromyographic (EMG) assessment has been used as a non-invasive tool to objectively assess muscle function, although with controversial research and clinical potential. The aim of this study was to assess within-, inter-subject and between-day repeatability of serial EMG recordings. The study sample included 10 asymptomatic subjects with no history of temporomandibular disorders or muscle parafunctions. Bilateral masseter and anterior temporalis muscle EMG parameters were assessed in two standardized serial recordings (day 1 to day 2) using a portable EMG equipment (ME 6000 recorder, Mega Electronics, Kuopio, Finland). The functional tasks included postural/resting activities as pre- and post-recording series of 30 s each and jaw opening/closing, intercuspal and maximal voluntary clenching activities of 5 s, repeated three times. The assessed EMG parameters included the mean amplitude, s.d. and error. In addition, the power spectrum EMG parameter assessment included the median power frequencies and the averaged EMG spectrum data values. The results of the intraclass correlation coefficient analysis indicated reliability for nearly all of the intercuspal and all clenching EMG amplitude and power spectrum parameters. This was complemented by the repeated measures anova and post hoc analyses that indicated non-significant differences between day 1 and 2 in task- and muscle-related analyses. Most variability was noted in postural and some in opening/closing tasks. In conclusion this study assessed the reliability, repeatability and limitations of postural and various dynamic masseter and temporalis EMG recordings for serial assessment.

BOLD fMRI deactivation of limbic and temporal brain structures and mood enhancing effect by transcutaneous vagus nerve stimulation

Direct vagus nerve stimulation (VNS) has proved to be an effective treatment for seizure disorder and major depression. However, since this invasive technique implies surgery, with its side-effects and relatively high financial costs, a non-invasive method to stimulate vagal afferences would be a great step forward. We studied effects of non-invasive electrical stimulation of the nerves in the left outer auditory canal in healthy subjects (n = 22), aiming to activate vagal afferences transcutaneously (t-VNS). Short-term changes in brain activation and subjective well-being induced by t-VNS were investigated by functional magnetic resonance imaging (fMRI) and psychometric assessment using the Adjective Mood Scale (AMS), a self-rating scale for current subjective feeling. Stimulation of the ear lobe served as a sham control. fMRI showed that robust t-VNS induced BOLD-signal decreases in limbic brain areas, including the amygdala, hippocampus, parahippocampal gyrus and the middle and superior temporal gyrus. Increased activation was seen in the insula, precentral gyrus and the thalamus. Psychometric assessment revealed significant improvement of well-being after t-VNS. Ear lobe stimulation as a sham control intervention did not show similar effects in either fMRI or psychometric assessment. No significant effects on heart rate, blood pressure or peripheral microcirculation could be detected during the stimulation procedure.

CONCLUSIONS

Our study shows the feasibility and beneficial effects of transcutaneous nerve stimulation in the left auditory canal of healthy subjects. Brain activation patterns clearly share features with changes observed during invasive vagus nerve stimulation.

Cerebral representation of the anorectum using functional magnetic resonance imaging

BACKGROUND

Anorectal continence depends not only on the organs of continence but also on cerebral control. There are relatively few data regarding cerebral processing of anorectal continence.

METHODS

Thirteen healthy subjects underwent rectal distension to cause urge increasing to discomfort during functional magnetic resonance imaging (fMRI). In addition, a painful heat stimulus was applied to the skin of the anterior abdominal wall in the dermatome corresponding to the rectum. Voluntary contraction of the anal sphincter was also performed. Subjective rating of stimulus intensity was recorded. Evaluation of the data used a general linear model with Brain Voyager(trade mark).

RESULTS

Subjective sensation of discomfort increased during repeated rectal distension and caused activation in the anterior cingulate gyrus, insula, thalamus and secondary somatosensory cortex seen on fMRI. Perception of rectal urge and discomfort activated the same cerebral regions with differing intensity. Application of a painful thermal stimulus in the corresponding dermatome showed a modification of the response. Voluntary contraction of the anal sphincter led to activation of the motor cortex and increased activity in the supplementary motor cortex and the insula.

CONCLUSION

Cerebral representation of the anorectum as mapped by fMRI is intricate and reflects the complexity of the continence mechanism.

Capsaicin-induced local elevations in collagenase-2 (matrix metalloproteinase-8) levels in human gingival crevice fluid

BACKGROUND AND OBJECTIVES

Application of capsaicin on alveolar mucosa provokes pain and neurogenic vasodilatation in the adjacent gingiva. Pain-associated inflammatory reactions may initiate expression of several pro-inflammatory mediators. Collagenase-2 (matrix metalloproteinase-8: MMP-8) is the major destructive protease, especially in the periodontitis-affected gingival crevice fluid (GCF). With this background, we wished to study whether capsaicin stimulation of alveolar mucosa can induce changes in the GCF MMP-8 levels.

MATERIAL AND METHODS

For 10 generally and periodontally healthy human volunteers, capsaicin (3%)-moistened filter paper was applied unilaterally to the buccal alveolar mucosa on the anterior maxilla. GCF samples were collected from the tooth at the stimulation site and from several other incisors in the upper jaw. MMP-8 levels and molecular forms in GCF samples were determined by immunofluorometric assay (IFMA) and western immunoblotting, respectively.

RESULTS

Capsaicin stimulation of the alveolar mucosa induced significant local elevations in levels and activation of MMP-8 in GCF of the adjacent teeth. Western immunoblot revealed that both neutrophil- and mesenchymal-type MMP-8 isoforms were elevated and activated, together with 110 kDa high-molecular size MMP-8 species. This capsaicin-evoked MMP-8 elevation lasted several minutes after stimulation. During the experiments, no marked changes occurred in MMP-8 levels in the GCF of distantly located teeth.

CONCLUSIONS

These results suggest that capsaicin-evoked neurogenic gingival inflammation can trigger the expression and activation of MMP-8 in GCF of the adjacent teeth.

Cortical representation of experimental tooth pain in humans

Cortical processing of electrically induced pain from the tooth pulp was studied in healthy volunteers with fMRI. In a first experiment, cortical representation of tooth pain was compared with that of painful mechanical stimulation to the hand. The contralateral S1 cortex was activated during painful mechanical stimulation of the hand, whereas tooth pain lead to bilateral activation of S1. The S2 and insular region were bilaterally activated by both stimuli. In S2, the center of gravity of the activation during painful mechanical stimulation was more medial/posterior compared to tooth pain. In the insular region, tooth pain induced a stronger activation of the anterior and medial parts. The posterior part of the anterior cingulate gyrus was more strongly activated by painful stimulation of the hand. Differential activations were also found in motor and frontal areas including the orbital frontal cortex where tooth pain lead to greater activations. In a second experiment, we compared the effect of weak with strong tooth pain. A significantly greater activation by more painful tooth stimuli was found in most of those areas in which tooth pain had induced more activation than hand pain. In the medial frontal and right superior frontal gyri, we found an inverse relationship between pain intensity and BOLD contrast. We concluded that tooth pain activates a cortical network which is in several respects different from that activated by painful mechanical stimulation of the hand, not only in the somatotopically organized somatosensory areas but also in parts of the 'medial' pain projection system.

Tau suppression in a neurodegenerative mouse model improves memory function

Neurofibrillary tangles (NFTs) are the most common intraneuronal inclusion in the brains of patients with neurodegenerative diseases and have been implicated in mediating neuronal death and cognitive deficits. Here, we found that mice expressing a repressible human tau variant developed progressive age-related NFTs, neuronal loss, and behavioral impairments. After the suppression of transgenic tau, memory function recovered, and neuron numbers stabilized, but to our surprise, NFTs continued to accumulate. Thus, NFTs are not sufficient to cause cognitive decline or neuronal death in this model of tauopathy.

BOLD effects in different areas of the cerebral cortex during painful mechanical stimulation

The contribution of four cortical areas (S1, S2, insular cortex and gyrus cinguli) to pain processing was assessed by functional magnetic resonance imaging (fMRI). Phasic (mechanical impact) and tonic stimuli (squeezing) were applied to the back of a finger, both at two different strengths. Stimuli were adjusted to inflict weak and strong pain sensations. It had been shown before that stronger noxious mechanical stimuli induce a weaker input from myelinated mechanoreceptors, but a more vigorous input from nociceptive primary afferents, and vice versa. Sizes of activation clusters and percent increase of the blood oxygenation level dependent (BOLD) signal during activation were compared in the areas of interest. Phasic stimulus patterns were more closely reflected in the time course of the MR signal in S1, S2 and the cingulate than tonic patterns, since the tonic stimuli tended to induce slow MR signal increase also during the resting periods which is in parallel to the persisting character of the tonic pain sensations. In S1 only the contralateral side was activated in most cases, and the more painful stimuli did not induce greater BOLD responses compared to the less painful stimuli in this area. Paradoxically, more painful stimuli produced smaller activation clusters in S1, both in tonic and phasic stimulus trials. In contralateral S2 more painful phasic stimuli induced significantly stronger BOLD responses than the weaker stimuli. The responses to tonic stimuli did not differentiate painfulness and were significantly smaller than the phasic. Activation clusters in this area were also smaller for tonic stimuli. In the gyrus cinguli more painful phasic stimuli induced stronger BOLD responses, but no difference was seen between tonic stimulation of different strength. Though the insular cortex was often bilaterally activated, no significant differences between stimulus quality or intensity were found. Our results provide evidence for a contribution of the S2 projection area and of the cingulate cortex to the processing of the intensity dimension of phasic mechanical pain. Such evidence was not found for the S1 area, which probably receives dominant input from non-nociceptive mechanoreceptors.

Factors associated with coronary artery calcification in young female patients with SLE

BACKGROUND

With improved survival rates of patients with systemic lupus erythematosus (SLE), damage such as accelerated atherosclerosis gains increasing importance.

OBJECTIVE

To identify the prevalence of coronary artery calcifications (CAC) in asymptomatic patients.

METHODS

Electron beam tomography (EBT) was performed in 75 female patients with SLE aged <50. The results were correlated with traditional and SLE related factors associated with CAC. 49 women with symptomatic coronary heart disease (CHD) and 279 women without CHD were also analysed.

RESULTS

Overall, 21/75 (28%) patients had CAC. Low HDL cholesterol levels <1.40 mmol/l (p=0.03, OR=1.8, 67% v 39%) and cigarette smoking (p=0.01, OR=5.7, 76% v 44%) were identified as factors associated with CAC. Hypertension and high cholesterol were more common in women with CHD (p<0.01) than in those without CHD. SLE related factors were proteinuria (1331 v 465 mg/day, p=0.02), impaired renal function (p=0.02, OR=2.6, 26% v 6%), and high C3 levels (p=0.04, OR=1.8, 65% v 38%). High C3 levels were also more common in symptomatic CHD (p=0.02). The prevalence of Sm antibodies was lower in patients with CAC (15% v 42%, p=0.03). In a multivariate analysis, cigarette smoking, reduced renal function, high C3, and a cumulative steroid dose above 30 g were the most important CAC associated factors in the lupus cohort.

CONCLUSION

A subgroup of patients with SLE with CAC without any clinical symptoms of CHD was identified by EBT. Therefore, EBT is useful for assessing asymptomatic atherosclerosis in this group.

Laser capture microdissection and real-time PCR for analysis of glomerular endothelin-1 gene expression in mesangiolysis of rat anti-Thy 1.1 and murine Habu Snake Venom glomerulonephritis

Molecular analysis of pathologic changes in glomeruli requires methods allowing rapid and exact detection of alterations in gene expression. Here, we analyzed endothelin-1 (ET-1) mRNA expression in mesangiolytic glomeruli during the course of a rat and murine model of mesangioproliferative glomerulonephritis (GN). A novel method combining laser capture microdissection (LCM), which permits the precise removal of selected mesangiolytic glomeruli, with a highly sensitive real-time RT-PCR technique was used. Anti-Thy 1.1. GN was introduced in male Sprague-Dawley rats (1.0 mg/kg body weight of OX-7 IV) and Habu Snake Venom GN was introduced in C57BL6 mice (habu snake venom toxin 6 mg/kg body weight IV). The degree of mesangiolysis during both GNs was analyzed using a semiquantitative scoring system. Mesangiolytic glomeruli were microdissected at different days of the diseases (day 2, 6, and 12 in anti-Thy 1.1 GN and days 1, 3, 7, and 14 in Habu Snake Venom GN) and from normal control animals. After RNA extraction and cDNA synthesis, ET-1 gene expression was measured by real-time RT-PCR. In parallel, in anti-Thy 1.1. GN ET-1 mRNA expression was analyzed using semiquantitative nonradioactive in situ hybridization; ET-1 protein expression was investigated by immunohistochemistry. Mesangiolysis peaked at day 6 in anti-Thy1.1 GN and at day 1 in Habu Snake Venom GN. Mesangiolytic glomeruli were easily microdissected on cryostat sections in both models; quantification of mRNA with RT-PCR was reliable and reproducible. Glomerular ET-1 mRNA expression increased during the course of anti-Thy 1.1 GN and Habu Snake Venom GN peaked when mesangiolysis was most pronounced. This was seen by RT-PCR after glomerular LCM and by in situ hybridization; in parallel, glomerular ET-1 protein expression was increased. Combination of LCM and RT-PCR is a reliable method for quantification of localized gene expression in isolated renal structures. The above data argue for an important role of ET-1 in pathogenesis and/or repair of mesangiolysis in experimental mesangioproliferative GN.

Low-threshold heat receptor in chick sensory neurons is upregulated independently of nerve growth factor after nerve injury

In mammals, the cloned low-threshold heat receptor, vanilloid receptor subtype 1 (VR1), is involved in the genesis of thermal hyperalgesia after inflammation. However, there is evidence that VR1 is not involved in the thermal hyperalgesia that occurs after nerve injury. In search for other heat receptors which might be involved in this phenomenon, we previously demonstrated that chick dorsal root ganglion neurons, which are insensitive to capsaicin, respond to low-threshold heat. Here, we investigated whether expression of the low-threshold noxious heat receptor in chicks is regulated by nerve growth factor (NGF), as VR1 is in mammals. Heat (44 degrees C) responsiveness of isolated dorsal root ganglion neurons of chicks was investigated (i) under culture conditions for up to 4 days with and without NGF and (ii) after a tight ligation of the sciatic nerve for up to 6 days, using cobalt-uptake method. In every case, a significant upregulation in the proportion of heat-responsive neurons was observed. On the molecular level, there was an increase of chick VR1 mRNA level in dorsal root ganglion cells cultured for 3 days in medium lacking NGF. In rat dorsal root ganglion neurons cultured for 1-4 days without NGF, patch-clamp experiments revealed that after 1 day almost all neurons responding to heat also responded to capsaicin, whereas after 3-4 days, more than one-half of the heat-responsive neurons did not respond to capsaicin. These data suggest the existence of low-threshold heat receptors in chick dorsal root ganglion neurons, the expression of which is regulated independently of NGF.

Differences between tooth stimulation and capsaicin-induced neurogenic vasodilatation in human gingiva

Animal experiments have shown that the application of capsaicin to oral mucosa leads to a neurogenic inflammation associated with blood flow elevations in gingivomucosal tissues. In this investigation, we measured the tooth stimulation and capsaicin-evoked blood flow responses in maxillary gingiva in humans to study whether axon-reflex-mediated vasodilatation crosses the midline of the maxilla. The vasoactive reactions were mapped by laser Doppler imaging. Unilateral stimulation of alveolar mucosa and attached gingiva by capsaicin evoked a distinct neurogenic vasodilatation in ipsilateral gingiva, which rapidly attenuated at the midline. Capsaicin stimulation of alveolar mucosa provoked clear inflammatory reactions. In contrast to capsaicin stimuli, tooth stimulation produced symmetrical vasodilatations bilaterally in the gingiva. The ipsilateral responses were significantly smaller during tooth stimulation than during capsaicin stimuli. Analysis of these data suggests that capsaicin-induced inflammatory reactions in gingivomucosal tissues do not cross the midline in the anterior maxilla. The enhanced reaction found during stimulation of alveolar mucosa indicates that alveolar mucosa is more sensitive to chemical irritants than attached gingiva.

Blood flow increase in the human lip after high-intensity tooth stimulation is not based on cholinergic mechanisms

The purpose of this study was to investigate whether parasympathetic cholinergic pathways are involved in the regulation of orofacial blood flow. The effect of atropin (1 mg, iv.) on blood flow responses in the lower lip, nose and hand during painful tooth stimulation was studied in healthy human subjects (n=8). In all subjects, tooth stimulation caused a long lasting vasodilatation in the lower lip. During stimulation there was a transient elevation in heart rate (HR) and blood pressure (BP) concomitantly with a blood flow decrease in the finger and nose. With atropin, the pain-induced HR and BP elevations and blood flow reductions in the nose and finger were decreased. However, the pain-induced blood flow increase in the lip was not changed. This study indicates that the tooth stimulation-induced vasodilatation in the lip is not based on parasympathetic cholinergic mechanisms.

Cyclooxygenase-2 inhibitor ns-398 protects neuronal cultures from lipopolysaccharide-induced neurotoxicity

BACKGROUND AND PURPOSE

The prostanoid-synthesizing enzyme cyclooxygenase (COX)-2 is markedly upregulated after cerebral ischemia and may participate in the mechanisms by which postischemic inflammation contributes to the late stages of ischemic brain injury. In the present study, we sought to provide additional evidence for a role of COX-2 in the mechanisms of neurotoxicity associated with inflammation.

METHODS

Nine-day-old neuronal-glial cultures, prepared from the cerebral cortex of newborn C57BL/6J mice, were exposed to lipopolysaccharide (LPS), a potent proinflammatory agent. The contribution of COX-2 was investigated by using the COX-2 inhibitor NS-398.

RESULTS

LPS produced a dose-dependent (0.001 to 10 microg/mL) and selective neuronal death that was well developed 72 hours after treatment. The effect was associated with a marked increase in the concentration of the COX reaction product prostaglandin E(2) (PGE(2)) and of the cytokine tumor necrosis factor-alpha (TNF-alpha). NS-398 (10 micromol/L) blocked the PGE(2) increase, attenuated the TNF-alpha increase, and prevented the neuronal death produced by LPS. TNF-alpha-blocking antibodies attenuated LPS-induced neuronal death, but the protection was less pronounced than that afforded by NS-398. LPS failed to elevate PGE(2) or to produce cell death in neuron-enriched cultures, suggesting that glial cells are required for these effects.

CONCLUSIONS

COX-2, in part through TNF-alpha-related mechanisms, contributes to LPS-induced neuronal death. The data support the hypothesis that COX-2, in addition to its role in glutamate excitotoxicity, participates in the cytotoxicity associated with inflammation.

Structural alterations of adhesion mediating components in cells cultured on poly-beta-hydroxy butyric acid

Polymers may serve as a biodegradable material in tissue engineering. To assess the biocompatibility of poly-beta-hydroxy butyric acid (PHB), we studied the structural organization of cellular molecules involved in adhesion using osteoblastic and epithelial cell lines. On PHB, both cell lines revealed a rounded cell shape due to reduced spreading. The filamentous organization of the actin cytoskeleton was impaired. In double immunofluorescence analyses we demostrated that the colocalization of the fibronectin fibrils with the actin filaments was lost in cultures on PHB. Similarly, collagen II distribution was altered, whereas the organization of collagen I was not obviously affected. Further evidence for impaired structural organization was obtained for the beta1-integrin receptor and vinculin which mediate the interaction of the cytoskeleton with the extracellular matrix. In confluent epithelial cells, the tight junction protein ZO-1 showed a larger lateral extension in the cell-cell contacts when cells were grown on PHB. Because structural organization of components which mediate cell-matrix and cell-cell adhesion controls cell physiology these parameters could be a sensitive indicator for the biocompatibility of implant materials.

Seizure's outcome after cortical resections including the face and tongue rolandic areas in patients with refractory epilepsy and normal MRI submitted to subdural grids' implantation

PURPOSE

To study the seizure's outcome in patients with refractory epilepsy and normal MRI submitted to resections including the rolandic cortex.

METHODS

Four adult patients were studied. All patients had motor or somatosensory simple partial seizures and normal MRI and were submitted to subdural grids' implantation with extensive coverage of the cortical convexity (1 in the non-dominant and 3 in the dominant hemisphere).

RESULTS

ECoG was able to define focal areas of seizures' onset in every patient. All patients were submitted to resection of the face and tongue motor and sensitive cortex; two patients had resections including the perirolandic cortex and 2 had additional cortical removals. Three patients are seizures' free and one had a greater then 90% reduction in seizure frequency.

CONCLUSION

Resections including the face and tongue rolandic cortex can be safely performed even within the dominant hemisphere.

Results of surgery in patients with refractory extratemporal epilepsy with normal or nonlocalizing magnetic resonance findings investigated with subdural grids

PURPOSE

To study the efficacy of extensive coverage of the brain surface with subdural grids in defining extratemporal cortical areas amenable for resection in patients with refractory extratemporal epilepy (R-ExTE) and normal or nonlocalizing magnetic resonance imaging (MRI) scans.

METHODS

Sixteen patients with R-ExTE were studied. Eleven patients had simple partial, eight had complex partial, and three had supplementary motor area seizures. Seizure frequency ranged from three per month to daily episodes. Interictal EEG showed large focal spiking areas in 11 patients, secondary bilateral synchrony in four, and was normal in one patient. Surface ictal recordings were nonlocalizing in six patients, and in 10, they disclosed large ictal focal spiking areas. MRI was normal in 10 patients, and in six patients, focal nonlocalizing potentially epileptogenic lesions were found. All patients were given an extensive coverage of the cortical convexity with subdural electrodes through large unilateral (n = 13) or bilateral (n = 3) craniotomies. Bipolar cortical stimulation was carried out through the implanted electrodes.

RESULTS

Interictal invasive recording findings showed widespread spiking areas in 13 patients and secondary bilateral synchrony in three. Ictal invasive recordings showed focal seizure onset in all patients. There were six frontal, two parietal, one temporooccipital, four rolandic, and three posterior quadrant resections. Thirteen patients had been rendered seizure free after surgery, and three had > or =90% of seizure-frequency reduction. Pathologic findings included gliosis (n = 10), cortical dysplasia (n = 5), or no abnormalities (n = 1). Six patients had transient postoperative neurologic morbidity.

CONCLUSIONS

Extensive subdural electrodes coverage seems to be an effective way to investigate patients with R-ExTE and normal or nonlocalizing MRI findings.

The importance of stimulus site and intensity in differences of pain-induced vascular reflexes in human orofacial regions

Studies in anaesthetized animals have indicated that noxious stimulation may produce marked blood flow changes in various orofacial structures, but the influence of painful stimulation on the blood flow regulation of the orofacial area of humans has been studied only to a limited extent. The purpose of this investigation was to study whether there are differences in temporal and spatial patterns of pain-induced vasoactive reflexes between various orofacial regions and hand in healthy human volunteers. Dynamic changes in blood flow in various orofacial regions elicited by painful stimulation of the tooth and finger were measured by means of Laser Doppler imaging (LDI) and computer-assisted infrared thermography (IRT). Blood flow of the finger was recorded by laser Doppler flowmetry (LDF) and plethysmography (PLET). During both stimulus paradigms there was a transient elevation in heart rate (HR) and blood pressure (BP). At the same time there was a significant blood flow decrease in the finger (LDF, PLET) and in the nose (LDI, IRT). In contrast to tooth stimulation, finger stimulation caused a more marked blood flow reduction in the finger. Only high intensity tooth stimulation, but not finger stimulation, caused a long-lasting vasodilatation both in lower and upper lip. The blood flow changes in the lips were not correlated with changes in systemic blood pressure or heart rate. In the cheek, there were no marked flow changes during either finger or tooth stimulation. These data indicate that painful tooth (regional) stimulation, but not finger (remote) stimulation, can induce a long-lasting vasodilatation in parts of orofacial tissues which cannot be explained by changes in central cardiovascular parameters. This tooth-stimulation-induced blood flow increase supports the hypothesis of a special vasodilator reflex mechanism in the orofacial area. Furthermore, tooth-stimulation-induced vasoconstriction in the nose and dilatation in the lips indicate that separate vasoactive reflex mechanisms may exist for different orofacial regions.

Cytosolic Ca2+ homeostasis is a constitutive function of the V-ATPase in Saccharomyces cerevisiae

The vacuole is the major site of intracellular Ca(2+) storage in yeast and functions to maintain cytosolic Ca(2+) levels within a narrow physiological range via a Ca(2+) pump (Pmc1p) and a H(+)/Ca(2+) antiporter (Vcx1p) driven by the vacuolar H(+)-ATPase (V-ATPase). We examined the function of the V-ATPase in cytosolic Ca(2+) homeostasis by comparing responses to a brief Ca(2+) challenge of a V-ATPase mutant (vma2Delta) and wild-type cells treated with the V-ATPase inhibitor concanamycin A. The kinetics of the Ca(2+) response were determined using transgenic aequorin as an in vivo cytosolic Ca(2+) reporter system. In wild-type cells, the V-ATPase-driven Vcx1p was chiefly responsible for restoring cytosolic Ca(2+) concentrations after a brief pulse. In cells lacking V-ATPase activity, brief exposure to elevated Ca(2+) compromised viability, even when there was little change in the final cytosolic Ca(2+) concentration. vma2Delta cells were more efficient at restoring cytosolic [Ca(2+)] after a pulse than concanamycin-treated wild-type cells, suggesting long term loss of V-ATPase triggers compensatory mechanisms. This compensation was dependent on calcineurin, and was mediated primarily by Pmc1p.

Results of surgery in patients with bilateral independent temporal lobe spiking (BITLS) with normal MRI or bilateral mesial temporal sclerosis (MTS) investigated with bilateral subdural grids

PURPOSE

The introduction of new technologies in the clinical practice have greatly decreased the number of patients submitted to invasive recordings. On the other hand, some patients with refractory temporal lobe epilepsy have normal MR scans or bilateral potentially epileptogenic lesions. This paper reports the results of invasive neurophysiology and surgical outcome in such patients.

METHOD

Sixteen patients were studied. Eleven had normal MRI (Group I) and five had bilateral mesial temporal sclerosis (Group II). All patients had BITLS and non-localizatory seizures on video-EEG monitoring. All patients were implanted bilaterally with 32-contacts subdural grids. They were submitted to a cortico-amygdalo-total hippocampectomy at the side defined by chronic electrocorticography (ECoG).

RESULTS

In Group I, seizures came from a single side in nine patients. In nine patients, seizures started at one side, spread to the ipsolateral contacts and contralaterally afterwards. On the other hand, in two Group I patients seizures started in one mesial region and spread to the contralateral parahippocampus and neocortex before spreading to ipsolateral contacts. All patients in Group II had seizures starting unilaterally with focal EcoG onset in the mesial regions. Eight Group I patients are seizure-free and three are in Engel's class II. Eighty percent of Group II patients are seizure-free after surgery and one patient is in Engel's class II.

CONCLUSION

Good surgical results can be obtained in patients with BITLS. Patients with normal MRI seem to have a worse prognosis when compared to patients with unilateral or even bilateral MTS. Extensive subdural coverage is essential in patients with normal MRI.

Paradigms for subdural grids' implantation in patients with refractory epilepsy

RATIONALE

The need for invasive monitoring in patients with refractory epilepsy has been greatly reduced by the introduction of new technologies such as PET, SPECT and MRI in the clinical practice. On the other hand, 10 to 30% of the patients with refractory epilepsy have non-localizatory non-invasive preoperative work-up results. This paper reports on the paradigms for subdural electrodes implantation in patients with different refractory epileptic syndromes.

METHODS

Twenty-nine adult refractory epileptic patients were studied. Patients were divided into five different epileptic syndromes that represented the majority of the patients who needed invasive recordings: bitemporal (Group I; n=16 ), bi-frontal-mesial (Group II, n=5), hemispheric (Group III; n=2), anterior quadrant (Group IV; n=3) and posterior quadrant (Group V; n=3). All of them were submitted to extensive subdural electrodes' implantation (from 64 to 160 contacts) covering all the cortical surface potentially involved in epileptogenesis under general anesthesia.

RESULTS

All patients tolerated well the procedure. There was no sign or symptom of intracranial hypertension except for headache in 22 patients. In all except one Group II patient, prolonged electrocorticographic monitoring using the described subdural cortical coverage patterns was able to define a focal area amenable for resection. In all Groups II-V patients cortical stimulation was able to adequately map the rolandic and speach areas as necessary.

CONCLUSION

Despite recent technological advances invasive neurophysiological studies are still necessary in some patients with refractory epilepsy. The standardization of the paradigms for subdural implantation coupled to the study of homogeneous patients' populations as defined by MRI will certainly lead to a better understanding of the pathophysiology involved in such cases and an improved surgical outcome.

UVB-irradiated T-cells undergoing apoptosis lose L-selectin by metalloprotese-mediated shedding

PURPOSE

L-selectin (CD62L) is a prerequisite for leucocyte adhesion to endothelial cells of blood vessels and consequently for transmigration. Its expression on the cell surface therefore regulates the ability of lymphocytes to enter lymph nodes, to re-enter blood vessels or to invade tissues at sites of inflammation. The aim of this study was to determine the expression of CD62L on apoptotic lymphocytes after UVB irradiation.

MATERIALS AND METHODS

Peripheral blood mononuclear cells (PBMC) were isolated from peripheral blood of normal healthy volunteers. Cells were stimulated with phorbol myristate acetate (PMA) and ionomycin for activation. Apoptosis in peripheral T-cells and Jurkat cells was induced by irradiation with UVB (120 mJ/cm2). In addition, T-cells or Jurkat cells were cultured for the indicated time with anti-Fas antibody CH11. The CH11-induced apoptosis was inhibited by the pan-caspase inhibitor zVAD-fmk. For detection of apoptosis, cells were analysed by cytofluorometry for morphological changes typical for apoptosis. The reliability of the apoptotic cell gate was confirmed by staining with FITC-labelled annexin-V in the presence ofpropidium iodide (PI). For FACS analysis of CD62L expression on the cell-surface immunofluorescence was performed using FITC-conjugated anti-CD62L and PE-conjugated anti-CD3 antibodies. Soluble CD62L (sCD62L) in the cell supernatants was measured by standard ELISA technique. Assays were performed in the presence and absence of metalloprotease inhibitor KB8301.

RESULTS

PBMC from healthy volunteers undergoing apoptosis following UVB irradiation selectively shed CD62L, whereas the expression of the lineage-specific marker CD3 showed only minor changes. Shedding was blocked by the hydroxamic acid-based metalloprotease inhibitor KB8301. When Jurkat cells were treated with the caspase inhibitor zVAD-fmk, anti-CD95 antibodies did not induce apoptosis, and the expression of CD62L remained unaltered.

CONCLUSION

UVB or ionizing radiation induce apoptosis in lymphocytes. The loss of CD62L is associated with apoptosis and will influence lymphocyte trafficking and, by excluding them from CD62L-mediated adhesion and tissue invasion, might contribute to the regulation of inflammation.

Low-dose radiotherapy selectively reduces adhesion of peripheral blood mononuclear cells to endothelium in vitro

BACKGROUND AND PURPOSE

The anti-inflammatory effect of low-dose radiotherapy (LD-RT) still is not understood. The adhesion of leukocytes to endothelial cells (EC) of the vessel wall is the initial event of tissue invasion, and thus, crucially contributes to the regulation of inflammation. We investigated the influence of LD-RT on the adhesion process in vitro.

MATERIALS AND METHODS

Isolated peripheral-blood-mononuclear-cells (PBMC) were incubated with an activated murine endothelioma cell-line under shear conditions at 4 degrees C after irradiation with single doses between 0.1 and 10.0 Gy. Adherent cells were counted microscopically and compared to a non-irradiated control. In parallel, viability and expression of adhesion molecules, especially of L-selectin, and lineage-specific markers on the cell surface were determined by dye exclusion and cytofluorometry, respectively. Modulation of adhesion by soluble L-selectin was tested in the adhesion assay.

RESULTS

Radiation doses of 0.1-0.5 Gy reduced the adhesion of viable PBMC to EC in vitro by 70% of the control level 4 h after irradiation. Leukocytes showed a marked reduction of L-selectin expression after LD-RT. Soluble L-selectin can inhibit the adhesion of PBMC to EC.

CONCLUSION

The anti-inflammatory effect of LD-RT might, in part, be due to the reduction in the adhesion of PBMC to EC. This reduction in adhesion might be a consequence of the reduced expression of L-selectin on the surface of PBMC, and the inhibition of adherence by soluble L-selectin shed by PBMC in vitro.

The angiotensin II-receptor antagonist losartan does not prevent hemodynamic or vascular tolerance to nitroglycerin

Tolerance may involve increased production of angiotensin II. We tested the hypothesis that losartan would prevent the development of tolerance to continuous transdermal nitroglycerin (GTN). Twenty volunteers received losartan, 75 mg/day, or placebo in a randomized, double-blind, parallel fashion. After 1 week, continuous transdermal GTN, 0.6 mg/h, was given, in addition to losartan or placebo, to all volunteers for 1 week. Standing systolic blood pressure (SBP) and heart rate were measured, and forearm venous volume responses to sublingual GTN were evaluated. Measurements were made at baseline, after 1 week of losartan versus placebo, 3 h after initial therapy with transdermal GTN, and after 1 week of continuous transdermal GTN given in combination with losartan versus placebo. After sustained GTN therapy, SBP was unchanged from baseline in both groups, indicating that losartan did not prevent the development of tolerance. Tolerance also developed to the forearm venous volume responses and was not prevented by losartan. Therapy with an angiotensin II-receptor antagonist does not prevent the development of tolerance to continuous transdermal GTN.

Secondary bilateral synchrony due to fronto-mesial lesions. An invasive recording study

Frontal lobe epilepsies may present difficulties in focus localization in the pre-operative work-up for epilepsy surgery. This is specially true in patients with normal MRIs. We report on a 16 years-old girl that started with seizures by the age of 8 years. They were brief nocturnal episodes with automatisms such as bicycling and boxing. Seizure frequency ranged from 4-10 per night. Scalp EEG showed few right frontal convexity spiking and intense secondary bilateral synchrony (SBS). High resolution MRI directed to the frontal lobes was normal. Ictal SPECT suggested a right fronto-lateral focus. Ictal video-EEG showed no focal onset. She was submitted to invasive recordings after subdural plates implantation. Electrodes covered all the frontal convexity and mesial surface bilaterally. Ictal recordings disclosed stereotyped seizures starting from the right mesial frontal. Using a high-resolution tool to measure intra and interhemispheric latencies, the timing and direction of seizure spread from the right fronto-mesial region were studied. Motor strip mapping was performed by means of electrical stimulation. She was submitted to a right frontal lobe resection, 1.5 cm ahead of the motor strip and has been seizure free since surgery (8 months). Pathological examination found a 4 mm area of cortical dysplasia. Invasive studies are needed to allow adequate localization in patients with non-localizatory non-invasive work-up and may lead to excellent results in relation to seizures after surgery.

In vitro apoptosis in peripheral blood mononuclear cells induced by low-dose radiotherapy displays a discontinuous dose-dependence

PURPOSE

Cells undergoing apoptosis contribute to the regulation of activated mononuclear cells (Voll et al. 1997). Low-dose radiotherapy (LD-RT) is known to improve inflammatory symptoms, but the mechanism of action is still unclear. The aim of this study was to investigate the rate of apoptosis of peripheral blood mononuclear cells (PBMC) induced by LD-RT within the therapeutic dose range of anti-inflammatory RT.

MATERIALS AND METHODS

PBMC were isolated from venous blood of ten healthy volunteers and were irradiated with single doses between 0.1 and 3.0 Gy. Apoptotic nuclei were detected by flow cytometry after propidium iodide (PI) triton staining, and apoptotic cells were detected by annexin V/PI staining and cell scatter analysis. Since apoptotic cells display increased cytoplasmatic granularity and concomitant reduced cell size, they can be distinguished from viable cells in forward/side scatter (FSC/SSC) histograms. Apoptotic PBMC were further subtyped by double staining with annexin V and directly labelled monoclonal antibodies recognizing the lineage-specific surface markers CD4, CD8, and CD19, respectively. The apoptosis rate of irradiated cells was analysed in a time and dose dependent fashion and was compared to a sham-irradiated control.

RESULTS

After irradiation, a dose-dependent increase in apoptosis was observed, with a discontinuity (plateau or peak) between 0.3Gy and 0.7Gy in 9/10 donors (90%) and 59/80 samples (74%). 8/10 donors (80%) and 38/80 samples (47%) showed not only a discontinuous increase with a plateau but a relative maximum of apoptosis peaking within the dose range of 0.3 Gy and up to 0.7 Gy.

CONCLUSION

LD-RT induces a relative maximum of apoptosis in PBMC in the does range between 0.3 Gy and 0.7 Gy. This may contribute to its anti-inflammatory effect observed clinically.