Solitary Pulmonary Lesion in Patients with History of Malignancy: Primary Lung Cancer or Metastatic Cancer?

BACKGROUND: Defining the status of solitary pulmonary lesion (SPL) in patients with history of malignancy is important because primary lung cancer (PLC) or intrapulmonary metastasis might indicate different surgical strategies. The aim of this study is to identify factors related to the status of these lesions and construct a clinical model to estimate the pretest probability of PLC. METHODS: From January 2005 to January 2016, 104 patients with previous malignancy and suitable for surgery were retrospectively studied. Univariate and multivariate analyses were performed to identify possible factors related to SPLs. A nomogram was constructed to differentiate PLC from intrapulmonary metastasis. RESULTS: Ninety-seven (93.3%) patients were diagnosed as malignant postoperatively, including 61 patients with intrapulmonary metastasis and 36 patients with PLC. Multivariate analysis showed that site of primary tumor [head and neck squamous cell cancer: odds ratio (OR) = 28.509, P = 0.006; genitourinary cancer: OR = 23.928, P = 0.012], negative lymph node status of primary tumor (OR = 3.154, P = 0.038), spiculation of SPL (OR = 3.972, P = 0.022), and central location of SPL (OR = 4.679, P = 0.026) were four independent factors differentiating PLC from intrapulmonary metastasis. All of these were included in the nomogram. The C-index of the nomogram for predicting probability was 0.82. CONCLUSIONS: Incidence of malignant SPLs was fairly high in patients with history of malignancy. A nomogram including site and lymph node status of primary tumor, and spiculation and location of SPL might be a good tool for differentiating PLC from intrapulmonary metastasis preoperatively and guiding treatment.

Chronic exposure to morphine decreases the expression of EAAT3 via opioid receptors in hippocampal neurons.

Alterations in glutamate transporter expression are closely related to opiate addition behavior, but the role of opioid receptors is unclear. In this study, we used primary cultures of hippocampal neurons from neonatal rats to study the effects of chronic exposure to morphine on excitatory amino acid transporter 3 (EAAT3) expression and the roles of µ opioid receptor (MOR), δ opioid receptor (DOR), and κ opioid receptor (KOR) in the morphine-dependent alterations in EAAT3 expression. The results showed that the EAAT3 protein and mRNA expression levels decreased significantly after chronic exposure to morphine (10µmol/L) for 48h, whereas the concentration of extracellular glutamate increased. In addition, we found that both the MOR inhibitor CTOP and the DOR inhibitor naltrindole could reverse the decreased expression of EAAT3 after exposure to morphine, whereas the MOR activator DAMGO and the DOR activator DPDPE significantly decreased EAAT3 expression. The KOR inhibitor had no effect on the expression of EAAT3, whereas its activator increased EAAT3 expression. These results suggest that the down-regulation of morphine-dependent EAAT3 expression in primary rat hippocampal cultures may be mediated by MOR and DOR and that KOR may not contribute significantly to this effect.

Both JNK and P38 MAPK pathways participate in the protection by dexmedetomidine against isoflurane-induced neuroapoptosis in the hippocampus of neonatal rats.

Dexmedetomidine, a highly selective α2-adrenergic agonist, has been reported to attenuate isoflurane-induced cognitive impairment and neuroapoptosis. However, the underlying molecular mechanisms remain poorly understood. The aim of this study was to investigate whether mitogen-activated protein kinase (MAPK) pathway was involved in dexmedetomidine-induced neuroprotection against isoflurane effects. Seven-day-old (P7) neonatal Sprague-Dawley rats were pretreated with various concentrations of dexmedetomidine, and then exposed to 0.75% isoflurane or air for 6h. Terminal deoxyribonucleotide transferase-mediated dUTP nick end labeling (TUNEL) was used to detect neuronal apoptosis in their hippocampus. Activated caspase-3, extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH2-terminal kinases (JNK), p38, phospho-ERK1/2, phospho-JNK and phospho-p38 proteins were detected by Western blotting in the hippocampus at the end of exposure. Also, P7 rats were pretreated with 75 µg/kg dexmedetomidine alone, or given the ERK inhibitor U0126 before dexmedetomidine pretreatment, or pretreated with the p38 MAPK inhibitor SB203580 or JNK inhibitor SP600125 alone, and then exposed to 0.75% isoflurane for 6h. Isoflurane induced significant neuroapoptosis, increased the protein expression of phospho-JNK, phospho-c-Jun, phospho-p38 and phospho-nuclear factor-κB (NF-κB), decreased the level of phospho-ERK1/2 protein and reduced the ratio of Bcl-2/Bax in the hippocampus. Dexmedetomidine pretreatment inhibited isoflurane-induced neuroapoptosis and restored proteins expression of MAPK pathways and the Bcl-2/Bax ratio after isoflurane exposure. Moreover, SB203580 and SP600125 also partly attenuated the isoflurane-induced protein changes. However, U0126 did not reverse dexmedetomidine-induced neuroprotection. Our results indicate that the JNK and p38 pathways, not the ERK pathway are involved in dexmedetomidine-induced neuroprotection against isoflurane effects.

Effects of the altered activity of δ-opioid receptor on the expression of glutamate transporter type 3 induced by chronic exposure to morphine.

Altered δ-opioid receptor (DOR) activity can affect the activity and function of excitatory amino acid transporter 3 (EAAT3), but the effects of DOR on EAAT3 expression in morphine relapse remain unknown. In this study, a C6δ cell line and SD rats in a conditioned place preference (CPP) reinstatement model were used. Here, we show that EAAT3 protein levels in C6δ cells decreased significantly after chronic exposure to morphine (10 µM) for 48 h and returned to normal 12 h after drug withdrawal. When C6δ cells were re-exposed to 5 µM morphine for 4 h, EAAT3 protein levels again decreased significantly. The selective µ opioid receptor (MOR) specific agonist DAMGO had a similar effect as morphine, and CTOP, a specific MOR blocker, reversed the declined expression of EAAT3 protein triggered by morphine exposure. The selective DOR agonist [d-pen2, 5] enkephalin (DPDPE) significantly increased EAAT3 expression in C6δ cells and even reversed the decreased EAAT3 expression caused by chronic morphine exposure. The non specific antagonist naloxone, but not the DOR inhibitor Naltrindole (NTI), reversed the decreased EAAT3 expression in C6δ cells caused by chronic morphine exposure. In vivo, EAAT3 levels in the prefrontal cortex of rats with morphine-induced CPP reinstatement significantly decreased. Naloxone completely suppressed reinstatement and reversed the decrease in EAAT3 expression induced by morphine re-exposure. In contrast, NTI only weakened CPP reinstatement and exerted no influence on EAAT3 expression. These findings suggest that DOR can affect the expression of EAAT3. However, the morphine-induced down-regulation of EAAT3 in C6δ cells and in the prefrontal cortex of rats may not be mediated by DOR.

[Remifentanil preconditioning lowers cardiac troponin I levels in patients undergoing off-pump coronary artery bypass graft surgery].

OBJECTIVE: To investigate the value of cardiac troponin I (cTnI) levels in assessing myocardial protection by remifentanil precondition against myocardial injury induced by off-pump coronary artery bypass (OPCAB). METHODS: Twenty-four patients undergoing OPCAB were randomized into control and remifentanil preconditioning group (n=12). All the patients received pretreatment with oral diazepam (10 mg), intramuscular morphine (10 mg) and hyosine (0.3 mg). General anesthesia was induced with midazolam (0.08 mg/kg), etomidate (0.1-0.3 mg/kg), fentanyl (5-10 microg/kg), and rocuronium (1 mg/kg), and maintained with isoflurane inhalation and propofol infusion. Intermittent fentanyl and pipecuronium were given intravenously. In remifentanil preconditioning group, remifentanil (5 microg/kg in 50 ml normal saline) was infused in 10 min after anesthesia induction, and only NS was administered in the control group. Blood samples were obtained before and at 0, 2, 6, 24, and 48 h after the operation to determine serum cTnI levels. RESULTS: In both of the two groups, the cTnI levels increased significantly at the postoperative time points (0, 2, 6, 24, and 48 h) as compared with those before the operation (P<0.05). The cTnI levels of remifentanil preconditioning group were markedly decreased after the operation in comparison with those of the control group (P<0.05). CONCLUSION: Remifentanil preconditioning decreases the cTnI levels and reduces myocardial injury induced by OPCAB.

[Effect of levosimendan on B-type natriuretic peptide levels in patients with advanced heart failure: a meta-analysis].

OBJECTIVE: To conduct a meta-analysis of the effect of levosimendan on B-type natriuretic peptide (BNP) levels and evaluate the therapeutic effect of levosimendan on advanced heart failure. METHODS: A meta-analysis was performed on the selected data to analyze the effect of levosimendan on BNP levels. RESULTS: Levosimendan decreased BNP by a mean of 337.66 [95%CI (-296.30, -379.02)] pg/ml 24 h after the administration, and by 259.92 [95%CI (-195.76, -324.08)] pg/ml at 48 h, and by 123.09 [95%CI(-53.32,-195.86)] pg/ml at 1 week. Levosimendan resulted in improvements of the cardiac function by about 29%, 22%, and 10% at 24 h, 48 h and 1 week after the administration. CONCLUSION: Levosimendan produces favorable effects on the cardiac functions and BNP levels.

Activation of PI3-K/Akt pathway for thermal preconditioning to protect cultured cerebellar granule neurons against low potassium-induced apoptosis.

AIM: This study was designed to investigate whether the activation of the phosphatidylinositol 3-kinase (PI3-K)/Akt pathway is required for thermal preconditioning to protect rat cerebellar granule neurons (CGN) against apoptosis induced by low potassium, and to explore the possibility of a link between the upregulated heat shock protein (HSP)70 expression and Akt activation in the acquisition of neuroprotection induced by thermal preconditioning. METHODS: CGN cultured for 8 d in vitro were switched to 5K medium for 24 h after thermal preconditioning (TP; 43.5 degree for 90 min, then 37 degree for 1 h). To study the role of the PI3-K/Akt pathway, a PI3-K inhibitor, LY294002 (20 micromol/L) was added into the cultures 1 h before TP. 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay and fluorescein diacetate staining were used to determine cell viability. Hoechst 33258 staining and agar gel electrophoresis were used to test the morphological and biological characters of CGN. Western blot analysis was employed to detect the levels of phospho-Akt, phospho-glycogen synthase kinase 3beta (GSK3beta) Akt, GSK3beta, and HSP70. RESULTS: TP protected CGN against apoptosis induced by low potassium. LY294002 inhibited the neuroprotective effect on CGN induced by TP. TP induced a robust activation of Akt and the inactivation of GSK3beta via PI3-K. Furthermore, the activation of the PI3-K/Akt pathway by TP persisted for 24 h in the 5K cultures. LY294002 (20 micromol/L) failed to inhibit the upregulated HSP70 expression induced by TP. CONCLUSION: The activation of the PI3-K/Akt pathway is required for TP to protect CGN against apoptosis induced by low potassium, but the neuroprotective effect by Akt activation is not mediated through the downstream induction of HSP70 expression.