Morphologic and biochemical changes in male rat lung after surgical and pharmacological castration

The morphology of the rat lung was studied by light microscopy in different situations: after surgical and pharmacological castration and after administration of testosterone to the castrated rat to determine if the androgen is required to maintain the normal morphology of the lung. We also determined the effect of flutamide on the phospholipid composition of both the surfactant and microsomes of the lung. Rats were separated into five groups: I - control non-castrated rats, II - castrated rats sacrificed 21 days after castration, III - castrated rats that received testosterone daily from day 2 to day 21 after castration, IV - castrated rats that received testosterone from day 15 to day 21 after castration, and V - control rats injected with flutamide for 7 days. The amount of different phospholipids in the surfactant and microsomes of the lung was measured in group I and V rats. At the light microscopy level, the surgical and pharmacological castration provoked alterations in the morphology of the lung, similar to that observed in human lung emphysema. The compositions of surfactant and microsomes of the lung were similar to those previously reported by us for the surgically castrated rats. These results indicate that androgens are necessary for the normal morphology as well as for some metabolic aspects of the lung.

Nonsmall cell lung cancer: evaluation of 737 consecutive patients in a single institution

OBJECTIVE: To analyze surgical and pathological parameters and outcome and prognostic factors of patients with nonsmall cell lung cancer (NSCLC) who were admitted to a single institution, as well as to correlate these findings to the current staging system. METHOD: Seven hundred and thirty seven patients were diagnosed with NSCLC and admitted to Hospital do Cancer A. C. Camargo from 1990 to 2000. All patients were included in a continuous prospective database, and their data was analyzed. Following staging, a multidisciplinary team decision on adequate management was established. Variables included in this analysis were age, gender, histology, Karnofsky index, weight loss, clinical stage, surgical stage, chemotherapy, radiotherapy, and survival rates. RESULTS: 75.5% of patients were males. The distribution of histologic type was squamous cell carcinoma 51.8%, adenocarcinoma 43.1%, and undifferentiated large cell carcinoma 5.1%. Most patients (73%) presented significant weight loss and a Karnofsky index of 80%. Clinical staging was IA 3.8%, IB 9.2%, IIA 1.4%, IIB 8.1%, IIIA 20.9%, IIIB 22.4%, IV 30.9%. Complete tumor resection was performed in 24.6% of all patients. Surgical stage distribution was IA 25.3%, IB 1.4%, IIB 17.1%, IIIA 16.1%, IIIB 20.3%, IV 11.5%. Chemotherapy and radiotherapy were considered therapeutic options in 43% and 72%, respectively. The overall 5-year survival rate of nonsmall cell lung cancer patients in our study was 28%. Median survival was 18.9 months. CONCLUSIONS: Patients with NSCLC who were admitted to our institution presented with histopathologic and clinical characteristics that were similar to previously published series in cancer hospitals. The best prognosis was associated with complete tumor resection with lymph node dissection, which is only achievable in earlier clinical stages.

Application of control measures for infections caused by multi-resistant gram-negative bacteria in intensive care unit patients

Multi-resistant gram-negative rods are important pathogens in intensive care units (ICU), cause high rates of mortality, and need infection control measures to avoid spread to another patients. This study was undertaken prospectively with all of the patients hospitalized at ICU, Anesthesiology of the Hospital São Paulo, using the ICU component of the National Nosocomial Infection Surveillance System (NNIS) methodology, between March 1, 1997 and June 30, 1998. Hospital infections occurring during the first three months after the establishment of prevention and control measures (3/1/97 to 5/31/97) were compared to those of the last three months (3/1/98 to 5/31/98). In this period, 933 NNIS patients were studied, with 139 during the first period and 211 in the second period. The overall rates of infection by multi-resistant microorganisms in the first and second periods were, respectively, urinary tract infection: 3.28/1000 patients/day; 2.5/1000 patients/day; pneumonia: 2.10/1000 patients/day; 5.0/1000 patients/day; bloodstream infection: 1.09/1000 patients/day; 2.5/1000 patients/day. A comparison between overall infection rates of both periods (Wilcoxon test) showed no statistical significance (p = 0.067). The use of intervention measures effectively decreased the hospital bloodstream infection rate (p < 0.001), which shows that control measures in ICU can contribute to preventing hospital infections.

Gene expression profiling analysis of lung adenocarcinoma

The present study screened potential genes related to lung adenocarcinoma, with the aim of further understanding disease pathogenesis. The GSE2514 dataset including 20 lung adenocarcinoma and 19 adjacent normal tissue samples from 10 patients with lung adenocarcinoma aged 45-73 years was downloaded from Gene Expression Omnibus. Differentially expressed genes (DEGs) between the two groups were screened using the t-test. Potential gene functions were predicted using functional and pathway enrichment analysis, and protein-protein interaction (PPI) networks obtained from the STRING database were constructed with Cytoscape. Module analysis of PPI networks was performed through MCODE in Cytoscape. In total, 535 upregulated and 465 downregulated DEGs were identified. These included ATP5D, UQCRC2, UQCR11 and genes encoding nicotinamide adenine dinucleotide (NADH), which are mainly associated with mitochondrial ATP synthesis coupled electron transport, and which were enriched in the oxidative phosphorylation pathway. Other DEGs were associated with DNA replication (PRIM1, MCM3, and RNASEH2A), cell surface receptor-linked signal transduction and the enzyme-linked receptor protein signaling pathway (MAPK1, STAT3, RAF1, and JAK1), and regulation of the cytoskeleton and phosphatidylinositol signaling system (PIP5K1B, PIP5K1C, and PIP4K2B). Our findings suggest that DEGs encoding subunits of NADH, PRIM1, MCM3, MAPK1, STAT3, RAF1, and JAK1 might be associated with the development of lung adenocarcinoma.

Prevalence rates of infection in intensive care units of a tertiary teaching hospital

OBJECTIVE: To determine the prevalence rates of infections among intensive care unit patients, the predominant infecting organisms, and their resistance patterns. To identify the related factors for intensive care unit-acquired infection and mortality rates. DESIGN: A 1-day point-prevalence study. SETTING:A total of 19 intensive care units at the Hospital das Clínicas - University of São Paulo, School of Medicine (HC-FMUSP), a teaching and tertiary hospital, were eligible to participate in the study. PATIENTS: All patients over 16 years old occupying an intensive care unit bed over a 24-hour period. The 19 intensive care unit s provided 126 patient case reports. MAIN OUTCOME MEASURES: Rates of infection, antimicrobial use, microbiological isolates resistance patterns, potential related factors for intensive care unit-acquired infection, and death rates. RESULTS: A total of 126 patients were studied. Eighty-seven patients (69%) received antimicrobials on the day of study, 72 (57%) for treatment, and 15 (12%) for prophylaxis. Community-acquired infection occurred in 15 patients (20.8%), non- intensive care unit nosocomial infection in 24 (33.3%), and intensive care unit-acquired infection in 22 patients (30.6%). Eleven patients (15.3%) had no defined type. The most frequently reported infections were respiratory (58.5%). The most frequently isolated bacteria were Enterobacteriaceae (33.8%), Pseudomonas aeruginosa (26.4%), and Staphylococcus aureus (16.9%; [100% resistant to methicillin]). Multivariate regression analysis revealed 3 risk factors for intensive care unit-acquired infection: age > 60 years (p = 0.007), use of a nasogastric tube (p = 0.017), and postoperative status (p = 0.017). At the end of 4 weeks, overall mortality was 28.8%. Patients with infection had a mortality rate of 34.7%. There was no difference between mortality rates for infected and noninfected patients (p=0.088). CONCLUSION: The rate of nosocomial infection is high in intensive care unit patients, especially for respiratory infections. The predominant bacteria were Enterobacteriaceae, Pseudomonas aeruginosa, and Staphylococcus aureus (resistant organisms). Factors such as nasogastric intubation, postoperative status, and age ³60 years were significantly associated with infection. This study documents the clinical impression that prevalence rates of intensive care unit-acquired infections are high and suggests that preventive measures are important for reducing the occurrence of infection in critically ill patients.

Deletion, insertion and translocation of DNA sequences contribute to chromosome size polimorphism in Plasmodium berghei

Extensive chromosome size polymorphism in Plasmodium berghei in vivo mitotic multiplication. Size differences between homologous chromosomes mainly involve rearrangements in the subtelomeric regions while internal chromosomal regions are more conserved. Size differences are almost exclusively due to differences in the copy number of a 2.3 kb subtelomeric repeat unit. Not only deletion of 2.3 kb repeats occurs, but addition of new copies of this repeat sometimes results in the formation of enlarged chromosomes. Even chromosomes which originally lack 2.3 kb repeats, can acquire these during mitotic multiplication. In one karyotype mutant, 2.3 kb repeats were inserted within one of the original telomeres of chromosome 4, creating an internal stretch oftelomeric repeats. Chromosome translocation can contribute to chromosome size polymorphism as well We found a karyotype mutant in which chromosome 7 with a size of about 1.4 Mb is translocated to chromosome 13/14 with a size of about 3 Mb, resulting in a rearranged chromosome, which was shown to contain a junction between internal DNA sequences of chromosome 13/14 and subtelomeric 2.3 kb repeats of chromosome 7. In this mutant a new chromosome of 1.4 Mb is present which consists of part of chromosome 13/14.

Effects of diazepam on Mycobacterium bovis-induced infection in hamsters

The in utero exposure of hamsters to low doses of diazepam results in impaired host defense against Mycobacterium bovis during adulthood. Delayed developmental immunotoxicity, however, represents a specific situation that might not be general. The present experiment was undertaken to investigate the effects of diazepam on hamster resistance to M. bovis using adult animals. The effects of diazepam treatment on serum cortisol levels were also studied. Adult hamsters (N = 10 for each group) were treated with diazepam (E1 = 1.0, E2 = 2.0 or E3 = 3.0 mg kg-1 day-1 subcutaneously) or with control solution (C) for 30 days. Seven days after the beginning of the treatment, the animals received identical inoculum concentrations of M. bovis. Hamsters treated with the higher (2.0 and 3.0 mg kg-1 day-1) doses of diazepam exhibited: 1) increased granuloma areas in the liver (C = 1.81 ± 1.39, E2 = 10.29 ± 4.64 and E3 = 15.80 ± 4.82) and lung (C = 0.54 ± 0.55, E2 = 6.28 ± 3.85 and E3 = 6.31 ± 3.56) and 2) increased scores of M. bovis colony-forming units isolated from liver (C = 2.0, E2 = 3.0 and E3 = 3.5), lung (C = 1.0, E2 = 3.0 and E3 = 3.5) and spleen (C = 1.0, E2 = 2.5 and E3 = 4.0). These effects were dose dependent, and were not detected or were less severe in animals treated with the lowest (1.0 mg/kg) dose of diazepam as well as in those of the control group. Furthermore, diazepam treatment (3.0 mg kg-1 day-1 for 30 days) increased (E3 = 71.32 ± 2.99; N = 10) the serum levels of cortisol compared to control hamsters (C = 22.61 ± 2.75; N = 10). The present data, that demonstrate an impaired defense against M. bovis in adult hamsters treated with diazepam, were tentatively explained on the basis of a direct and/or indirect action of diazepam on the cytokine network. The effects may be related to stimulation of peripheral benzodiazepine receptor binding sites (PBR) by macrophages and/or lymphocytes, or they may be mediated by PBR stimulation of the adrenals.

Lung clearance of 99mTc-DTPA in systemic lupus erythematosus

The early demonstration of lung involvement in systemic lupus erythematosus (SLE) patients is a difficult but important task. In the present study we attempted to identify abnormalities in pulmonary clearance of 99mTc-DTPA in SLE, correlating their clearance data with clinical findings and disease activity. Forty-six consecutive SLE patients with and without active disease (LACC score) and 30 normal volunteers were studied. All subjects were submitted to pulmonary scintigraphy with 99mTc-DTPA to evaluate the pulmonary clearance, and to a chest X-ray, and SLE patients were submitted to tests of disease activity, spirometry, arterial blood gases and tests to assess acute-phase proteins. Pulmonary clearance was faster in SLE patients with active disease when compared to normal controls [half-life of 67.04 min (51.52-82.55 min) in active SLE versus 85.87 min (78.85-92.87 min) in controls, P<0.05] and there was a higher frequency of abnormal clearance rates in patients with active disease (11 of 26 patients, 42.3%) when compared with SLE patients without disease activity (2 of 20 patients, 10%) (P = 0.04). A significant correlation was observed between the clearance rates and cough (P<0.05), but not between the clearance rates and dyspnea symptoms or radiological findings, duration of SLE disease, antinuclear antibody titers and patterns, C-reactive protein or anti-double stranded DNA antibodies. We conclude that the pulmonary clearance of 99mTc-DTPA is increased in SLE patients with active disease.

One-year follow-up of the effects of sildenafil on pulmonary arterial hypertension and veno-occlusive disease

We hypothesized that chronic oral administration of the phosphodiesterase-5 inhibitor sildenafil could improve the exercise capacity and pulmonary hemodynamics in patients with pulmonary arterial hypertension (PAH) on the basis of previous short-term studies. We tested this hypothesis in 14 subjects with PAH, including seven patients with the idiopathic form and seven patients with atrial septal defects, but no other congenital heart abnormalities. Patients were subjected to a 6-min walk test and dyspnea was graded according to the Borg scale. Pulmonary flow and pressures were measured by Doppler echocardiography. Patients were given sildenafil, 75 mg orally three times a day, and followed up for 1 year. Sildenafil therapy resulted in the following changes: increase in the 6-min walk distance from a median value of 387 m (range 0 to 484 m) to 462 m (range 408 to 588 m; P < 0.01), improvement of the Borg dyspnea score from 4.0 (median value) to 3.0 (P < 0.01), and increased pulmonary flow (velocity-time integral) from a median value of 0.12 (range 0.08 to 0.25) to 0.23 (range 0.11 to 0.40; P < 0.01) with no changes in pulmonary pressures. In one patient with pulmonary veno-occlusive disease diagnosed by a lung biopsy, sildenafil had a better effect on the pulmonary wedge pressure than inhaled nitric oxide (15 and 29 mmHg, respectively, acute test). He walked 112 m at baseline and 408 m at one year. One patient died at 11 months of treatment. No other relevant events occurred. Thus, chronic administration of sildenafil improves the physical capacity of PAH patients and may be beneficial in selected cases of veno-occlusive disease.

Effect of melatonin administration on subjective sleep quality in chronic obstructive pulmonary disease

Disturbed sleep is common in chronic obstructive pulmonary disease (COPD). Conventional hypnotics worsen nocturnal hypoxemia and, in severe cases, can lead to respiratory failure. Exogenous melatonin has somnogenic properties in normal subjects and can improve sleep in several clinical conditions. This randomized, double-blind, placebo-controlled study was carried out to determine the effects of melatonin on sleep in COPD. Thirty consecutive patients with moderate to very severe COPD were initially recruited for the study. None of the participants had a history of disease exacerbation 4 weeks prior to the study, obstructive sleep apnea, mental disorders, current use of oral steroids, methylxanthines or hypnotic-sedative medication, nocturnal oxygen therapy, and shift work. Patients received 3 mg melatonin (N = 12) or placebo (N = 13), orally in a single dose, 1 h before bedtime for 21 consecutive days. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness was measured by the Epworth Sleepiness Scale. Pulmonary function and functional exercise level were assessed by spirometry and the 6-min walk test, respectively. Twenty-five patients completed the study protocol and were included in the final analysis. Melatonin treatment significantly improved global PSQI scores (P = 0.012), particularly sleep latency (P = 0.008) and sleep duration (P = 0.046). No differences in daytime sleepiness, lung function and functional exercise level were observed. We conclude that melatonin can improve sleep in COPD. Further long-term studies involving larger number of patients are needed before melatonin can be safely recommended for the management of sleep disturbances in these patients.

High mobility group box 1 as a mediator of endotoxin administration after hemorrhagic shock-primed lung injury

High mobility group box 1 (HMGB1) was discovered as a novel late-acting cytokine that contributes to acute lung injury (ALI). However, the contribution of HMGB1 to two-hit-induced ALI has not been investigated. To examine the participation of HMGB1 in the pathogenesis of ALI caused by the two-hit hypothesis, endotoxin was injected intratracheally in a hemorrhagic shock-primed ALI mouse model. Concentrations of HMGB1 in the lung of the shock group were markedly increased at 16 h (1.63 ± 0.05, compared to the control group: 1.02 ± 0.03; P < 0.05), with the highest concentration being observed at 24 h. In the sham/lipopolysaccharide group, lung HMGB1 concentrations were found to be markedly increased at 24 h (1.98 ± 0.08, compared to the control group: 1.07 ± 0.03; P < 0.05). Administration of lipopolysaccharide to the hemorrhagic shock group resulted in a notable HMGB1 increase by 4 h, with a further increase by 16 h. Intratracheal lipopolysaccharide injection after hemorrhagic shock resulted in the highest lung leak at 16 h (2.68 ± 0.08, compared to the control group: 1.05 ± 0.04; P < 0.05). Compared to the hemorrhagic shock/lipopolysaccharide mice, blockade of HMGB1 at the same time as lipopolysaccharide injection prevented significantly pulmonary tumor necrosis factor-alpha, interleukin-1beta and myeloperoxidase. Lung leak was also markedly reduced at 16 h; blockade of HMGB1 24 h after lipopolysaccharide injection failed to alter lung leak or myeloperoxidase at 48 h. Our observations suggest that HMGB1 plays a key role as a late mediator when lipopolysaccharide is injected after hemorrhagic shock-primed ALI and the kinetics of its release differs from that of one-hit ALI. The therapeutic window to suppress HMGB1 activity should not be delayed to 24 h after the disease onset.

Computed tomography assessment of lung structure in patients undergoing cardiac surgery with cardiopulmonary bypass

Hypoxemia is a frequent complication after coronary artery bypass graft (CABG) with cardiopulmonary bypass (CPB), usually attributed to atelectasis. Using computed tomography (CT), we investigated postoperative pulmonary alterations and their impact on blood oxygenation. Eighteen non-hypoxemic patients (15 men and 3 women) with normal cardiac function scheduled for CABG under CPB were studied. Hemodynamic measurements and blood samples were obtained before surgery, after intubation, after CPB, at admission to the intensive care unit, and 12, 24, and 48 h after surgery. Pre- and postoperative volumetric thoracic CT scans were acquired under apnea conditions after a spontaneous expiration. Data were analyzed by the paired Student t-test and one-way repeated measures analysis of variance. Mean age was 63 ± 9 years. The PaO2/FiO2 ratio was significantly reduced after anesthesia induction, reaching its nadir after CPB and partially improving 12 h after surgery. Compared to preoperative CT, there was a 31% postoperative reduction in pulmonary gas volume (P < 0.001) while tissue volume increased by 19% (P < 0.001). Non-aerated lung increased by 253 ± 97 g (P < 0.001), from 3 to 27%, after surgery and poorly aerated lung by 72 ± 68 g (P < 0.001), from 24 to 27%, while normally aerated lung was reduced by 147 ± 119 g (P < 0.001), from 72 to 46%. No correlations (Pearson) were observed between PaO2/FiO2 ratio or shunt fraction at 24 h postoperatively and postoperative lung alterations. The data show that lung structure is profoundly modified after CABG with CPB. Taken together, multiple changes occurring in the lungs contribute to postoperative hypoxemia rather than atelectasis alone.

Sildenafil prevents the increase of extravascular lung water and pulmonary hypertension after meconium aspiration in newborn piglets

Meconium aspiration syndrome causes respiratory failure after birth and in vivo monitoring of pulmonary edema is difficult. The objective of the present study was to assess hemodynamic changes and edema measured by transcardiopulmonary thermodilution in low weight newborn piglets. Additionally, the effect of early administration of sildenafil (2 mg/kg vo, 30 min after meconium aspiration) on this critical parameter was determined in the meconium aspiration syndrome model. Thirty-eight mechanically ventilated anesthetized male piglets (Sus scrofa domestica) aged 12 to 72 h (1660 ± 192 g) received diluted fresh human meconium in the airway in order to evoke pulmonary hypertension (PHT). Extravascular lung water was measured in vivo with a PiCCO monitor and ex vivo by the gravimetric method, resulting in an overestimate of 3.5 ± 2.3 mL compared to the first measurement. A significant PHT of 15 Torr above basal pressure was observed, similar to that of severely affected humans, leading to an increase in ventilatory support. The vascular permeability index increased 57%, suggesting altered alveolocapillary membrane permeability. Histology revealed tissue vessel congestion and nonspecific chemical pneumonitis. A group of animals received sildenafil, which prevented the development of PHT and lung edema, as evaluated by in vivo monitoring. In summary, the transcardiopulmonary thermodilution method is a reliable tool for monitoring critical newborn changes, offering the opportunity to experimentally explore putative therapeutics in vivo. Sildenafil could be employed to prevent PHT and edema if used in the first stages of development of the disease.

Propofol exerts anti-inflammatory effects in rats with lipopolysaccharide-induced acute lung injury by inhibition of CD14 and TLR4 expression

We investigated the effect of propofol (Prop) administration (10 mg kg-1 h-1, intravenously) on lipopolysaccharide (LPS)-induced acute lung injury and its effect on cluster of differentiation (CD) 14 and Toll-like receptor (TLR) 4 expression in lung tissue of anesthetized, ventilated rats. Twenty-four male Wistar rats were randomly divided into three groups of 8 rats each: control, LPS, and LPS+Prop. Lung injury was assayed via blood gas analysis and lung histology, and tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels were determined in bronchoalveolar lavage fluid using ELISA. Real-time polymerase chain reaction was used to detect CD14 and TLR4 mRNA levels, and CD14 and TLR4 protein expression was determined by Western blot. The pathological scores were 1.2 ± 0.9, 3.3 ± 1.1, and 1.9 ± 1.0 for the control, LPS, and LPS+Prop groups, respectively, with statistically significant differences between control and LPS groups (P < 0.05) and between LPS and LPS+Prop groups (P < 0.05). The administration of LPS resulted in a significant increase in TNF-α and IL-1β levels, 7- and 3.5-fold, respectively (P < 0.05), while treatment with propofol partially blunted the secretion of both cytokines (P < 0.05). CD14 and TLR4 mRNA levels were increased in the LPS group (1.48 ± 0.05 and 1.26 ± 0.03, respectively) compared to the control group (1.00 ± 0.20 and 1.00 ± 0.02, respectively; P < 0.05), while propofol treatment blunted this effect (1.16 ± 0.05 and 1.12 ± 0.05, respectively; P < 0.05). Both CD14 and TLR4 protein levels were elevated in the LPS group compared to the control group (P < 0.05), while propofol treatment partially decreased the expression of CD14 and TLR4 protein versus LPS alone (P < 0.05). Our study indicates that propofol prevents lung injury, most likely by inhibition of CD14 and TLR4 expression.

Propofol pretreatment attenuates lipopolysaccharide-induced acute lung injury in rats by activating the phosphoinositide-3-kinase/Akt pathway

The aim of this study was to investigate the effect of propofol pretreatment on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and the role of the phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) pathway in this procedure. Survival was determined 48 h after LPS injection. At 1 h after LPS challenge, the lung wet- to dry-weight ratio was examined, and concentrations of protein, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in bronchoalveolar lavage fluid (BALF) were determined using the bicinchoninic acid method or ELISA. Lung injury was assayed via lung histological examination. PI3K and p-Akt expression levels in the lung tissue were determined by Western blotting. Propofol pretreatment prolonged survival, decreased the concentrations of protein, TNF-α, and IL-6 in BALF, attenuated ALI, and increased PI3K and p-Akt expression in the lung tissue of LPS-challenged rats, whereas treatment with wortmannin, a PI3K/Akt pathway specific inhibitor, blunted this effect. Our study indicates that propofol pretreatment attenuated LPS-induced ALI, partly by activation of the PI3K/Akt pathway.