New mouse models with hypomorphic SUMF1 variants mimic attenuated forms of multiple sulfatase deficiency

Multiple sulfatase deficiency (MSD) is an ultrarare lysosomal storage disorder due to deficiency of all known sulfatases. MSD is caused by mutations in the Sulfatase Modifying Factor 1 (SUMF1) gene encoding the enzyme responsible for the post-translational modification and activation of all sulfatases. Most MSD patients carry hypomorph SUMF1 variants resulting in variable degrees of residual sulfatase activities. In contrast, Sumf1 null mice with complete deficiency in all sulfatase enzyme activities, have very short lifespan with significant pre-wean lethality, owing to a challenging preclinical model. To overcome this limitation, we genetically engineered and characterized in mice two commonly identified patient-based SUMF1 pathogenic variants, namely p.Ser153Pro and p.Ala277Val. These pathogenic missense variants correspond to variants detected in patients with attenuated MSD presenting with partial-enzyme deficiency and relatively less severe disease. These novel MSD mouse models have a longer lifespan and show biochemical and pathological abnormalities observed in humans. In conclusion, mice harboring the p.Ser153Pro or the p.Ala277Val variant mimic the attenuated MSD and are attractive preclinical models for investigation of pathogenesis and treatments for MSD.

Effectiveness of Game-Based Learning on Anxiety and Postoperative Self-Efficacy among Children Undergoing Surgery

Background Play is an integral part of a child's life that could be effectively implemented for hospitalized children as well. It plays an important role in alleviating the psychological burden and enhancing self-efficacy of children undergoing surgery. Children benefit from play or games because they enjoy learning through them. The present study aims to assess the effectiveness of game-based learning on anxiety and postoperative self-efficacy among children undergoing surgery.

Materials and Methods Using nonprobability purposive sampling technique, 80 school-age children undergoing surgery were selected. Children in the interventional group received game-based learning, whereas those in the control group received routine care. A numeric 0 to 10 state anxiety scale and a self-efficacy scale were used for assessing anxiety and postoperative self-efficacy of children. The obtained data was analyzed using descriptive and inferential statistics.

Results Mann–Whitney U test showed significant difference (p < 0.05) between the mean pre- and posttests scores of anxiety in intervention group. Comparison of posttests anxiety scores between the groups also showed a statistical significance (p < 0.05). When compared self-efficacy scores within intervention and control groups, Wilcoxon signed-rank test value was significant (p < 0.05). Whereas between groups comparison the Mann–Whitney U test value was significant (p < 0.05) at 24 and 48 hours after surgery.

Conclusion The study concluded that game-based learning is effective in maintaining adequate postoperative self-efficacy and reducing the anxiety among the children undergoing surgery.

Acute acalculous cholecystitis on a COVID-19 patient: a case report

INTRODUCTION

We report an extremely rare case of acute acalculous cholecystitis on a COVID-19 patient. In our knowledge, this is the first report of laparoscopic cholecystectomy performed on a COVID-19 patient.

PRESENTATION OF CASE

A COVID-19 patient was diagnosed with acute acalculous cholecystitis and a multidisciplinary team decided to perform a percutaneous transhepatic biliary drainage (PTBD) as the first treatment. SARS-CoV-2 RNA was not found in the bile fluid. Because of deterioration of the patient's clinical conditions, laparoscopic cholecystectomy had to be performed and since the gallbladder was gangrenous, the severe inflammation made surgery difficult to perform.

DISCUSSION

Acalculous cholecystitis was related with mechanical ventilation and prolonged total parenteral nutrition, in this case the gangrenous histopathology pattern and the gallbladder wall ischemia was probably caused by vascular insufficiency secondary to severe acute respiratory distress syndrome of COVID-19 pneumonia. The percutaneous transhepatic gallbladder drainage (PTBD) was performed according to Tokyo Guidelines because of high surgical risk. Laparoscopic cholecystectomy was next performed due to no clinical improvement. The absence of viral RNA in the bile highlights that SARS-CoV-2 is not eliminated with the bile while it probably infects small intestinal enterocytes which is responsible of gastrointestinal symptoms such as anorexia, nausea, vomiting, and diarrhoea.

CONCLUSIONS

Although the lack of evidence and guidelines about the management of patient with acute cholecystitis during COVID-19 pandemic, laparoscopic cholecystectomy, at most preceded by PTGBD on high surgical risk patients, remains the gold standard for the treatment of acute cholecystitis on COVID-19 patients.

Targeting and silencing of rhodopsin by ectopic expression of the transcription factor KLF15

The genome-wide activity of transcription factors (TFs) on multiple regulatory elements precludes their use as gene-specific regulators. Here we show that ectopic expression of a TF in a cell-specific context can be used to silence the expression of a specific gene as a therapeutic approach to regulate gene expression in human disease. We selected the TF Krüppel-like factor 15 (KLF15) based on its putative ability to recognize a specific DNA sequence motif present in the rhodopsin (RHO) promoter and its lack of expression in terminally differentiated rod photoreceptors (the RHO-expressing cells). Adeno-associated virus (AAV) vector-mediated ectopic expression of KLF15 in rod photoreceptors of pigs enables Rho silencing with limited genome-wide transcriptional perturbations. Suppression of a RHO mutant allele by KLF15 corrects the phenotype of a mouse model of retinitis pigmentosa with no observed toxicity. Cell-specific-context conditioning of TF activity may prove a novel mode for somatic gene-targeted manipulation.

Rhodopsin targeted transcriptional silencing by DNA-binding

Transcription factors (TFs) operate by the combined activity of their DNA-binding domains (DBDs) and effector domains (EDs) enabling the coordination of gene expression on a genomic scale. Here we show that in vivo delivery of an engineered DNA-binding protein uncoupled from the repressor domain can produce efficient and gene-specific transcriptional silencing. To interfere with RHODOPSIN (RHO) gain-of-function mutations we engineered the ZF6-DNA-binding protein (ZF6-DB) that targets 20 base pairs (bp) of a RHOcis-regulatory element (CRE) and demonstrate Rho specific transcriptional silencing upon adeno-associated viral (AAV) vector-mediated expression in photoreceptors. The data show that the 20 bp-long genomic DNA sequence is necessary for RHO expression and that photoreceptor delivery of the corresponding cognate synthetic trans-acting factor ZF6-DB without the intrinsic transcriptional repression properties of the canonical ED blocks Rho expression with negligible genome-wide transcript perturbations. The data support DNA-binding-mediated silencing as a novel mode to treat gain-of-function mutations.

DOI:http://dx.doi.org/10.7554/eLife.12242.001

Proteins called transcription factors bind to sections of DNA known as regulatory elements to activate or deactivate nearby genes. In animals, transcription factors typically have two sections: a “DNA-binding domain” that attaches to DNA, and an “effector domain” that is responsible for interacting with other proteins to regulate the gene’s expression.

Rhodopsin is a gene that encodes the instructions needed to make a light-sensitive protein in the eyes of humans and other animals. Botta et al. have now used this gene as an example to investigate whether proteins that contain a DNA-binding domain – but not an effector domain – can repress gene expression.

The experiments show that only a small section of the regulatory elements in the human Rhodopsin gene is actually required for the gene to be expressed. Botta et al. designed an artificial protein – referred to as ZF6-DB – that is able to bind to this section of DNA. The binding of ZF6-DB to this short DNA section was sufficient to switch off a Rhodopsin gene in living pig cells, and, unlike conventional transcription factors, seemed to have minimal impact other genes.

Next, Botta et al. used a virus to insert both the gene that encodes ZF6-DB and a normal copy of Rhodopsin into pigs. In these animals, ZF6-DB switched off the existing copy of Rhodopsin, but not the inserted copy so the cells produced a working form of the light-sensitive protein. Further experiments were carried out in mice that have both a faulty version and a normal copy of the Rhodopsin gene. ZF6-DB switched off the faulty Rhodopsin gene, which allowed the normal Rhodopsin gene to work without any interference from the faulty copy.

Mutations in Rhodopsin can cause an eye disease that leads to severe loss of vision in humans. These new findings could now guide future efforts to develop treatments for people with this condition. It will also be important to investigate how ZF6-DB binds to the regulatory elements in the Rhodopsin gene and whether a similar strategy could be used to alter the expression of other genes.

DOI:http://dx.doi.org/10.7554/eLife.12242.002

Interval-value Based Particle Swarm Optimization algorithm for cancer-type specific gene selection and sample classification

Microarray technology allows simultaneous measurement of the expression levels of thousands of genes within a biological tissue sample. The fundamental power of microarrays lies within the ability to conduct parallel surveys of gene expression using microarray data. The classification of tissue samples based on gene expression data is an important problem in medical diagnosis of diseases such as cancer. In gene expression data, the number of genes is usually very high compared to the number of data samples. Thus the difficulty that lies with data are of high dimensionality and the sample size is small. This research work addresses the problem by classifying resultant dataset using the existing algorithms such as Support Vector Machine (SVM), K-nearest neighbor (KNN), Interval Valued Classification (IVC) and the improvised Interval Value based Particle Swarm Optimization (IVPSO) algorithm. Thus the results show that the IVPSO algorithm outperformed compared with other algorithms under several performance evaluation functions.

Sensitization to rodents (mouse/rat) in an urban atopic population without occupational exposure living in Naples, Italy

BACKGROUND

Until now no data on allergic sensitization to rodents allergens in Western Europe and Italy are available. The aim of this report was to investigate clinical significance and characteristics of IgE-mediated sensitization to mouse/rat (M/Rt) allergens in atopic subjects not occupationally exposed to these animals and living in urban area of Naples.

METHODS

In 1765 consecutive outpatients, we selected all subjects with an immediate skin reaction to M/WRt dander clinical history including a carefijul evaluation ofthe modality of exposure, the results of skin-prick tests (SPTs) and specific IgE antibodies were recorded.

RESULTS

Among 1185 SPT-positive patients, 22 were sensitized to M/Rt dander (respectively 1.60% and 0.59%). No patient was mono-sensitized Only three of 22 patients reported indoor conditions suggesting presence of rodents allergens at home. All patients exhibited low degree of SPT positivity and low levels of circulating IgE antibodies to M/WRt. Highfrequency of concomitant allergic sensitization to pet (and other animal) dander has been found.

CONCLUSIONS

Our results suggest that role of allergic sensitization to rodents is negligible in atopic subjects without occupational exposure living in urban area of Naples. However, highly atopic individuals especially those already sensitized to common pet dander should be tested by SPTs/evaluation of serum specific IgE to rodents in the case they could begin an occupational exposure to M/Rt or keeping these animals as pets.

Social networks: a new source of psychological stress or a way to enhance self-esteem? Negative and positive implications in bronchial asthma

The Internet and, in particular, social networks are an increasingly important part of daily life for both adolescents and adults who maintain a virtual relationship with others sharing interests and goals. Very often, they disclose more about themselves online than they do in person. However, cyberbullying and cyberostracism can be problematic for adolescents and sensitive individuals, who might be negatively affected by social networks. Some studies have shown an increased risk of depression, whereas others suggest beneficial effects through enhanced communication, social connection, and self-esteem. Bronchial asthma is an increasingly frequent disease in the industrialized world, and psychological implications play a role in increasing or in reducing its severity. One year after the case report of an asthma exacerbation that may have been triggered by Facebook, it seems reasonable to analyze the effects of social networks on bronchial asthma.

Exhaled breath condensate as matrix for toluene detection: A preliminary study

The study was designed to investigate whether exhaled breath condensate, obtained by cooling exhaled air in spontaneous breathing, could be a suitable matrix for toluene quantitative analyses. Nine healthy subjects were exposed for a short period (20 min) to a known concentration of toluene. Exhaled breath condensate samples were collected before and at the end of the exposure, while the environmental concentration of toluene was continuously monitored. Toluene was analysed by head-space gas-chromatography mass spectrometry, and assay repeatability was also estimated in vitro. Baseline and post-exposure measurement of hippuric acid, the urinary toluene metabolite, was performed to assess current toluene exposure. Before the exposure toluene concentrations in the exhaled breath condensate were lower than the detectable limit in all subjects, while after the exposure toluene was detectable with a median value 0.35 microg l-1 (range 0.15-0.55 microg l-1) in all the exhaled breath condensate samples. As compared with the standard calibration in distilled water, the curves obtained by exhaled breath condensate were linear and comparable with the range examined in vivo for toluene. A significant correlation was found between the environmental toluene levels and toluene in the exhaled breath condensate at the end of exposure. Furthermore, a significant relationship between increased exhaled breath condensate toluene levels and urinary hippuric acid after the exposure was found. In conclusion, exhaled breath condensate is a promising matrix for toluene assessment, although its application in humans requires further investigations.

Selectivity of compounds isolated from the leaves of Nerium indicum Mill. on various human cancer cell lines

The leaves of Nerium indicum Mill. have been utilized traditionally to cure cancer. By Bioassay (BST) guided isolation method, six compounds were isolated from the CHCl3 extract of the leaves. Selectivity of these compounds (in 0.6-12,500 ng/ml) was tested on various human cancer (MCF7, EVSA-T, T47D, H226, IGROV, A498, WIDR, M19, HeLa) and normal (Vero) cells in vitro. Doxorubicin and cysplatin were used as positive controls. The result indicated that NiO2D (5alpha-oleandrin) possessed the best cytotoxic effect on HeLa cells (IC50, 8.38 x10(-6) mM) and NiO2C (16, 17-dehidrodeasetil-5alpha-oleandrin) on A498 cells (IC50, 1.43 x 10(-6) mM). Those two compounds were not cytotoxic to normal cell.

Validation study of nasal nitric oxide measurements using a hand-held electrochemical analyser

BACKGROUND

Exhaled nitric oxide (NO) measurement is a simple and non-invasive method for monitoring airway inflammation. Similarly, nasal NO has been proposed as a surrogate marker in inflammatory diseases of the upper airways, e.g. allergic rhinitis. A new portable analyser using an electrochemical sensor has been developed for measurements of exhaled NO, and its reproducibility and comparison with other analysers has been tested recently in healthy subjects and in patients with lower airways disease. The application of this hand-held analyser in nasal NO analysis was tested and compared to the gold standard represented by a chemiluminescence analyser.

MATERIALS AND METHODS

Thirty subjects including 15 patients with allergic rhinitis (AR) and 15 healthy subjects (HS) were studied. The intraindividual variability, calculated as the difference in nasal NO levels between two measurements from a single nasally exhaled breath manoeuvre, and the comparison between the electrochemical analyser (NIOX MINO, Aerocrine) and a chemiluminescence analyser (NOA, Sievers) were performed.

RESULTS

In AR patients mean nasal NO was 59.0 +/- 16.3 p.p.b. with the MINO and 58.3 +/- 15.6 p.p.b. with the NOA. In HS nasal NO was 49.1 +/- 10.8 p.p.b. with the MINO and 49.8 +/- 8.2 p.p.b. with the NOA. The Bland-Altman analysis showed bias values of 0.005 +/- 3.6 with the 95% limits of agreement from -6.97 to 6.98 p.p.b.

CONCLUSION

Measurements of nasal NO levels with a hand-held electrochemical analyser are reproducible and the results are comparable to a stationary chemiluminescence analyser.

Nitric oxide in upper airways inflammatory diseases

In the human respiratory tract, the main production sites of exhaled nitric oxide (NO) are the nose and paranasal sinuses. In the upper airways, NO has been suggested to be involved at different levels with regulatory, protective, defensive or deleterious effects. Therefore, we review some aspects of the origin, metabolism, and functions of NO in the upper airways, together with the role of NO in some upper airways inflammatory diseases. Furthermore, we discuss the recent improvements in nasal NO measurements, which may be useful to better characterize the involvement of the NO produced by nose and paranasal sinuses in upper airways inflammatory diseases such as allergic rhinitis, nasal polyposis, sinusitis, primary ciliary dyskinesia, and cystic fibrosis.

CD8+ T-cell alveolitis in familial pulmonary alveolar microlithiasis

Pulmonary alveolar microlithiasis (PAM) is a rare diffuse lung disease characterised by the accumulation of calcium phosphate microliths within the alveoli. The causative mechanism of PAM has only recently been discovered, and involves a gene mutation of sodium phosphate co-transporter, which is expressed by alveolar epithelial cells. This mutation may have variable consequences on the clinical phenotype. However, pulmonary cell immune phenotyping in familial PAM has not previously been assessed. In the present article, the analysis of bronchoalveolar lavage fluid of two siblings with PAM diagnosis revealed a pattern of lymphocytic alveolitis with accumulation of CD8+ T-cells. The clonal complexity of this lymphocyte's population was assayed by spectratyping, which showed an oligoclonal accumulation of T-cells with a restricted variable beta T-cell receptor (TCR) gene usage. TCR analysis in peripheral blood lymphocytes revealed no abnormal patterns of T-lymphocytes. In the pulmonary alveolar microlithiasis familial cases reported, CD8-mediated maladaptive immune response may have taken place in the bronchoalveolar compartment. The relationship between this immune dysregulation and genetic background in pulmonary alveolar microlithiasis warrants further investigation.

A Clinical Case of Chicken Infectious Anemia Disease and Virus DNA Detection in Naturally Infected Broilers in Greece

In this study, chicken infectious anemia virus (CIAV) DNA was detected from 12-day-old broilers. Clinical history showed that the clinical features were diarrhea, blue wing disease, depression, and death. Necropsy findings were pale liver, severe atrophy of bursa of Fabricius and thymus, and discoloration of the bone marrow as well as hemorrhages subcutaneously and a few in skeletal muscles. The majority of the necropsied broilers had developed gangrenous dermatitis. Histopathology showed hypoplasia of bone marrow and depletion of lymphocytes in spleen, bursa, and subcapsular thymic cortex. Karyorrhexis of lymphocytes was scattered in the thymic cortex and most pronounced in the bursal follicles. Eosinophilic intranuclear inclusion bodies were mainly located in lymphocytes of thymus, with a few in hemopoietic cells of bone marrow. CIAV DNA was detected by polymerase chain reaction from bursa, thymus, and bone marrow. A virus strain was detected and genetically characterized in 639 base pairs of VP1 gene. Phylogenetic analysis revealed that the Greek isolate was clustered together with isolates from Alabama, China, Slovenia, and Bangladesh.

Right ventricular performance in severe obesity. Effect of weight loss

BACKGROUND

The effects of severe obesity on right ventricular function in the absence of associated cardiopulmonary disease are not well known. Right myocardial performance index (R-MPI) is an echocardiographic index to non-invasively assess the right ventricular function. The aim of our study was to assess R-MPI in individuals with severe but uncomplicated obesity before and after a significant weight loss induced by bariatric surgery.

PATIENTS AND METHODS

Fifteen obese females (OB) without cardiovascular and pulmonary diseases were examined. In all subjects, R-MPI was calculated by Doppler echocardiography as the sum of isovolumetric contraction time and isovolumetric relaxation time divided by ejection time. Furthermore, pulmonary function test (PFT) and 6-min walking test (6mWT) were performed. Ten healthy subjects with normal weight (HS) were also evaluated as controls. R-MPI, PFT and 6mWT were also re-evaluated one year later in 12 obese subjects treated with gastric banding after a consistent weight loss (> 20%).

RESULTS

A prolongation of R-MPI was found in OB before bariatric surgery in comparison to the HS (0.47 +/- 0.04 and 0.29 +/- 0.05, respectively; P < 0.001). R-MPI significantly improved in OB 12 months after surgery (0.32 +/- 0.03) and was no longer different from HS. R-MPI positively correlated to body mass index (BMI). A significant association was found between the reduction of BMI after bariatric surgery and the distance walked during the 6mWT.

CONCLUSIONS

These results show a right ventricular dysfunction in severe uncomplicated obesity, associated with an impaired functional capacity which recovers after consistent weight loss.

Sounding airflow enhances aerosol delivery into the paranasal sinuses

BACKGROUND

The use of aerosol therapy is commonly suggested in the treatment of paranasal disorders but it is difficult to achieve an effective penetration of drugs into the sinuses. The authors have recently shown that an oscillating airflow produced by phonation (nasal humming) causes a large increase in the gas exchange between the nose and the paranasal sinuses. This is reflected by a high peak in nasally exhaled nitric oxide (NO) levels because NO accumulated in the sinuses is rapidly washed-out via the sinus ostia.

OBJECTIVE

This study was designed to test whether the increase in sinus gas exchange caused by an oscillating airflow could be used to enhance penetration of a drug into the sinuses.

MATERIALS AND METHODS

In six healthy subjects a nitric oxide-synthase inhibitor L-NAME was administrated into the nostrils by a jet nebulizer connected to a duck call, which could be modified to generate either a sounding airflow or a non-sounding airflow. The degree of L-NAME penetration into the sinuses was judged from the reduction in nasal NO during humming exhalations. Sinus drug deposition was also studied in a model of the nose and sinus.

RESULTS

In humans the delivery of L-NAME with the non-sounding airflow had no effect on the NO levels achieved during humming, whereas L-NAME administration with sound caused a significant 22-35% reduction in nasal NO. In the model the aerosol delivery with the sounding airflow caused a fourfold increase in sinus drug deposition as compared with an aerosol without sound.

CONCLUSION

A sounding airflow increases the delivery of an aerosolized drug into the paranasal sinuses.

Bayesian estimation of sensitivity and specificity of serum ELISA and faecal culture for diagnosis of paratuberculosis in Greek dairy sheep and goats

Latent class models were used to estimate the sensitivity (Se) and the specificity (Sp) of a serum ELISA and a faecal culture (FC) method for the diagnosis of paratuberculosis separately, in sheep and goats. The estimates were obtained by a Bayesian method. Possible dependence of diagnostic errors was investigated by comparing models where independence was assumed to models allowing for conditional dependence given the true disease status. ROC analysis for the serum ELISA was also performed and optimized cut-off values based on the misclassification cost term were determined. No evidence of conditional dependence was found. Assuming independence, posterior medians and 95% credible intervals for the Se(ELISA), Sp(ELISA), Se(FC) and Sp(FC), were 63% (42, 93%), 95% (90, 98%), 8% (2, 17%) and 98% (95, 100%) in goats and 37% (10, 80%), 97% (93, 99%), 16% (2, 48%) and 97% (95, 99%) in sheep. AUC was calculated 0.702 for sheep and 0.847 for goats. For the serum ELISA, there is need of species- and purpose-specific cut-off selection. For instance, with 20% prevalence situation and assuming equal and five-fold cost of a false negative to a false positive test result, the optimal cut-off is 0.3 and 0.05 in sheep, respectively, while it is 0.6 and 0.1 in goats, respectively. Serum ELISA performed better in goats than in sheep. Lowering the cut-off, in relation to the one recommended by the manufacturer, improved Se(ELISA) without seriously compromising Sp(ELISA), in either species.

Prevalence of BVDV infection in Greek dairy herds

Thirty-nine Greek dairy herds, totalling 6333 cattle, enrolled in a voluntary bovine viral diarrhoea virus (BVDV) eradication programme based on the identification and removal of persistently infected (PI) animals. The aim of this study was to estimate the prevalences of BVD antigen-positive and PI animals, and investigate the significance of the associations between the prevalence estimates and herd size. Initially, all animals were bled and examined for BVDV, using an antigen ELISA. A second sample was collected from the positive animals, after a period of at least three weeks. Animals retested positive were classified as PI. Antigen positive and PI animals were detected in all herds. The respective mean prevalences, adjusted for the test's accuracy and the herd-clustering effect, were 14% (95%CI: 11-18%) and 1.3% (0.8-1.8%), respectively. Herd size was not associated with the prevalence of antigen-positive or PI animals.

[Use of the Floating Ball for hepatic resection in cirrhotic patients affected by hepatocellular carcinoma]

Done to the improvement of knowledges in hepatic surgery and postoperative care, hepatocellular carcinoma (HCC) have been treated more and more frequently by hepatic resection. Aim of this study is to report an initial series of patients affected by HCC treated by hepatic resection utilizing a new water-cooled, high-density, monopolar device, the Tissuelink Monopolar Floating Ball (Tissuelink Medical Inc., Dover, NH, U.S.A.), in order to avoid bleeding during hepatic surgery. Sex, age, kind of disease, viral and Child status, type of surgical procedure, in association to lenght of surgical procedure, blood loss, utilization of the vascular clamping of the liver, hospital stay, morbidity and mortality have been analized. Six liver resections have been performed utilizing this new device. No vascular clamping was established except one. No mortality was recorded. Morbidity was ascites in one case and pleural effusion in a second one. In conclusion the Floating Ball reduces the intraoperative bleeding during hepatic resection in patients with HCC.

[Assessment of patient's comfort and functioning of a totally implantable venous system placed in the safenous vein]

BACKGROUND

When venous system of superior vena cava is not useful or when chest wall is not utilizable to place a reservoir, saphenous vein can be utilized for totally implantable venous access device (TIVAD) placement. Aim of this work is to establish the best location of the reservoir for the function and the comfort of the patient.

PATIENTS AND METHODS

All the patients submitted to TIVAD placement from January 1995 to October 2004 at the Department of Surgical Science, Organs Transplantations and Advanced Technologies of University of Catania have been considered to the present study. Age, sex, kind of disease, surgical procedure, early and late complications, function of the system and comfort to the patients in relation to the different site of reservoir placement have been studied.

RESULTS

447 TIVAD have been implanted in 258 males and 189 females aged from 31 to 79 years in the period considered for the study. Solid tumors represent the majority of the indications and all the TIVAD have been implanted by surgical cutdown to avoid all the early complications related to the percutaneous approach. Two patients received their TIVAD using saphenous vein by surgical cut-down, and no early complications have been recorded. The reservoirs have been placed respectively: in the chest wall in the first patient; and in the anterior wall of the abdomen, close to the anterosuperior iliac crest, firstly and later in the anterolateral face of the thigh in the second one. The first patient had non complications instead the second one referred discomfort with both reservoir locations.

CONCLUSIONS

For the comfort of the patient related to the reservoir position in case of saphenous vein utilization chest wall should represent the best studies are required to validate the appropriate reservoir location.

[Colorectal liver metastases resected with safe margin achieved by tissuelink monopolar floating ball]

BACKGROUND

Nowadays many technological devices are present in hepatic surgery to permit safer liver resections. Main purpose is decrease the intraoperative blood loss. The aim of this study is to analyze our initial experience in hepatic resections for liver metastasis using the new water-cooled, high-density, monopolar device, the Tissuelink Monopolar Floating Ball and Dissecting Sealer (Tissuelink Medical, Inc., Dover, NH).

MATERIALS AND METHODS

We analyzed patients who underwent hepatic surgery for metastases from colorectal cancer between January 2003 and December 2004. Sex, age, type of surgical procedure, duration of the surgical procedure, blood loss, use of vascular clamping of the liver, length of hospital stay, morbidity, and mortality were analyzed.

RESULTS

Three liver resection, one segmentectomy and two limited resections were performed with the use of these new devices. In one case the devices was used to increase safe free margin of hepatic resection. Average blood loss was 150 ml (range, 50 to 300 ml). No mortality or morbidity were recorder.

CONCLUSIONS

In conclusion, this new device permits a bloodless liver resection avoiding vascular clamping. In plus the effect of radiofrequency waves can be useful to enlarge free resection border in patients submitted to hepatic resection without macroscopically safe margins. Prospective randomized studies are needed in order to establish the effective usefulness.

[Peritonectomy and hyperthermic chemoperfusion in peritoneal carcinomatosis. Preliminary results]

BACKGROUND

Peritoneal carcinomatosis can be actually treated by new surgical and oncological techniques. Aim of this work is to report preliminary results of a group of patients with peritoneal carcinomatosis, submitted to peritonectomy and intraperitoneal hypertermic chemoperfusion (IPHC).

METHODS

Age, sex, type of neoplasm, peritoneal carcinomatosis index (PCI), completeness of cytoreduction (CC), operative time, morbidity and mortality of patients submitted to IPHC have been considered.

RESULTS

From May 2001 to December 2004, 10 patients were submitted to peritonectomy and IPHC: 9 (90%) females and 1 (10%) male, aged from 49 to 72 years. Seven patients (70%) were affected of peritoneal carcinomatosis from ovarian tumor, three patients (30%) from colon cancer. The PCI was ranged from 8 to 25. The operative time was ranged from 6 to 14 hours. Two patients with a CC of 2 developed relaps and died respectively after 2 and 4 months. The remaining patients had a CC between 0 and 1. Of these last patients, 1 affected by ovarian cancer died 24 months after, 1 patient died 3 days after surgery for septic shock; the other patients are still alive with a period ranged from 1 to 30 months.

CONCLUSIONS

Our preliminary results suggest that the peritonectomy and IPHC can be effective only in patients with CC of 0 or 1, in the remaining cases these therapeutical methods should be avoided.

[Rule of early diagnosis for sigmoid volvulus. Case report]

The sigmoid colon is the most frequent site for a volvulus due to anatomical and pathological reasons. When the rotation of the loop occurs slowly, the sigma can greatly blow up and stretch. We report the clinical case of an 80-year-old woman admitted to our Department for an enormous volvulus of sigmoid colon. Physical examination, abdominal X-ray and CT-scan were performed to diagnose the disease. At the surgical procedure the sigma was about 50 centimetres in length and 15 centimetres in diameter, with a gangrenous necrosis of the loop; the treatment was a sigmoidectomy by Hartmann procedure. Surgical resection is the only therapeutical option for volvulus in advanced stage due to a late diagnosis.

Humming-induced release of nasal nitric oxide for assessment of sinus obstruction in allergic rhinitis: pilot study

BACKGROUND

Humming greatly increases nasal nitric oxide (NO) in healthy people by causing a rapid washout of NO from the sinuses. This increase is abolished in patients with complete sinus ostial obstruction.

OBJECTIVE

Allergic rhinitis is a risk factor for development of sinusitis and we wanted to study whether nasal NO measurement during humming could be used to detect sinus abnormalities in this disorder.

METHODS

Fifty-nine consecutive subjects with mild to moderate allergic rhinitis were studied. Their present nasal symptoms were recorded. Then NO levels were measured by chemiluminescence during quiet single-breath nasal exhalations and humming exhalations at a fixed exhalation flow of 0.2 L s(-1). Based on the NO results the patients were divided into two groups: those with a great increase in nasal NO during humming (humming responders, n = 46) and those without a significant increase (humming nonresponders, n = 13). In 11 of the nonresponders and in 22 of the responders the passage to the osteomeatal complex area was assessed and scored by nasal endoscopy. This was carried out by an oto-rhino-laryngologist unaware of the NO results.

RESULTS

Among the nonresponders nine of 11 patients (80%) had endoscopic signs of bilateral sinus obstruction, compared with one of the 22 (< 5%) humming responders. Baseline nasal symptom score and NO levels during quiet exhalation were not significantly different between the groups

CONCLUSION

Absence of a nasal NO peak during humming is associated with endoscopic findings suggestive of sinus ostial obstruction in subjects with allergic rhinitis. Measurement of nasal NO during humming may be a simple method to detect sinus abnormalities in these patients.

[Learning curve and early complications of totally implantable venous access devices: is tutoring the solution for the problem?]

During the last years operators implanting totally implantable venous access devices (TIVADs), type of access, and kind of complications are changed. Aim of this work is to evaluate the incidence of early complications during the learning curve of residents in surgery or inexperienced surgeons, besides considering the tutoring to evaluate its rule to prevent early complications. TIVADs, implanted by residents in surgery or by inexperienced surgeons in the Department of Surgical Science Organ Transplantation and Advanced Technologies of University of Catania from January 1995 to October 2003, have been considered for the present study. Age and sex of the patients, indication, type of surgical access and early complications of the TIVADs have been considered. Early complications are those complications that occur within 30 day after the implant. Ninety-five TIVADs were implanted by surgical approach in 95 patients: 58 males (61%) and 37 females (39%), with a mean age of 55 years (range 31-79). Inexperienced surgeons performed 40 implants (42%) instead resident in surgery implanted 55 TIVADs (58%). The migration out of the vein of a catheter 20 days after the operation was the only complication recorded. TIVADs implant by cut-down technique represent the way to avoid early complications. The learning curve is short and the tutoring is limited at the first phase.

Nasal nitric oxide measurements before and after repeated humming maneuvers

BACKGROUND

It has been recently shown that humming greatly increases nasal nitric oxide (NO). This is most likely owing to a rapid washout of sinus NO caused by the oscillating sound waves. During repeated humming manoeuvres nasal NO gradually decreases, likely because NO accumulated in the sinuses is washed out.

AIM

We studied whether humming before measurements would affect nasally exhaled NO.

MATERIALS AND METHODS

NO output was measured by the chemiluminescence technique in orally and nasally exhaled air in 38 subjects: 18 healthy subjects (HS), 15 subjects with allergic rhinitis (AR) and five subjects with allergic nasal polyposis (AP). Each subject performed a NO measurement during quiet nasal exhalation either preceded by a period of silence/free speaking or immediately after five consecutive humming manoeuvres (posthumming).

RESULTS

Mean nasal NO output (95% CI) after a period of silence/free speaking was 231 nL min-1 (178-284) in HS, 434 nL min-1 (347-522) in AR (P < 0.001) and 262 nL min-1 (163-361) in AP. Post-humming nasal NO output was 16% (5 to 50%) lower in HS and 14% (1 to 49%) lower in AR, while it remained unchanged in AP subjects. Intra-subject coefficient of variation of quiet nasal exhalation was 12% in HS, 13% in AR and 5% in AP. Post humming intraindividual coefficient of variation significantly decreased in both HS and AR, but it did not change in AP.

CONCLUSIONS

Nasal NO levels measured immediately after repeated humming manoeuvres are consistently lower and more reproducible than nasal NO levels measured after a period of silence or free speaking. Repeated humming effectively empties the sinuses, thereby probably minimizing the normal contribution from the sinuses to nasal NO. This may be useful to better estimate NO output from the nasal cavity mucosa in health and disease.

Assessment of nasal and sinus nitric oxide output using single-breath humming exhalations

Nasal nitric oxide (NO) levels increase greatly during humming compared to silent exhalation. In this study, the physiological and anatomical factors that regulate NO release during humming have been characterised in 10 healthy subjects and in a model of the sinus and the nose. Single-breath humming caused a large initial peak in nasal NO output, followed by a progressive decline. The NO peak decreased in a step-wise manner during repeated consecutive humming manoeuvres but recovered completely after a silent period of 3 min. Topical nasal application of an NO synthase inhibitor reduced nasal NO by >50% but had no effect on the increase evoked by humming. Silently exhaled nasal NO measured immediately after repeated humming manoeuvres was between 5-50% lower than basal silent NO exhalation, suggesting variable continuous contribution from the sinuses to nasal NO. Among the factors known to influence normal sinus ventilation, ostium size was the most critical during humming, but humming frequency was also of importance. In conclusion, humming results in a large increase in nasal nitric oxide, which is caused by a rapid gas exchange in the paranasal sinuses. Combined nasal nitric oxide measurement with and without humming could be of use to estimate sinus ventilation and to better separate nasal mucosal nitric oxide output from sinus nitric oxide in health and disease.

Inhaled ultrasonically nebulized distilled water decreases exhaled nitric oxide in asthma

Exhaled nitric oxide (eNO) is increasingly used as a marker of disease activity in asthma. Inhaled hypertonic saline has been shown to induce bronchoconstriction and to decrease eNO in asthmatic subjects, whereas the effects of hypotonic solutions on eNO in these patients have not been studied. To evaluate the effect of ultrasonically nebulized distilled water (UNDW), an indirect hypotonic stimulus, on eNO, 17 asthmatic patients were enrolled and eNO from lower airways was measured by chemiluminescence. UNDW significantly reduced FEV(1) >or= 20% in 9 subjects (UNDW+), but had no effect in eight patients (UNDW-). Baseline eNO concentration were found to be 51.3 +/- 11.1 ppb in UNDW+ and 32.9 +/- 7.5 ppb in UNDW- patients, respectively ( p = 0.199, NS). UNDW inhalation significantly decreased eNO (from 51.3 +/- 11.1 ppb to 31.0 +/- 7.1 ppb in UNDW+ ( p < 0.020, n = 9) and from 32.9 +/- 7.5 ppb to 26.2 +/- 7.3 ppb in UNDW- subjects ( p < 0.024, n = 8), respectively). eNO percentage reduction in UNDW+ patients was significantly higher compared with UNDW- subjects (-37 +/- 4% vs -23 +/- 3%, p = 0.021). There was no correlation between FEV(1) changes and eNO percentage decreases in both UNDW+ and UNDW- subjects. In UNDW+ patients, acute bronchodilation induced by salbutamol caused a recovery in both FEV(1) and eNO, though eNO levels remained lower than baseline values. We concluded that UNDW inhalation can significantly decrease eNO in asthmatic patients, either responders or nonresponders to this indirect osmotic challenge; the reduction in eNO levels was only partly dependent on acute changes in airway caliber.

Nitric oxide attenuates platelet-activating factor induced nasal airway plasma extravasation in healthy subjects

BACKGROUND

Paranasal sinuses and the nose are important sources of nitric oxide (NO) in humans but the relevance of NO production to the control of nasal airway plasma exudation and its response to inflammatory mediators such as platelet-activating factor (PAF) in healthy subjects is not well known.

DESIGN

In this study we aimed to evaluate the effect of the nitric oxide synthase (NOS) inhibitor NG L-arginine methyl ester (L-NAME) on nasal airway plasma extravasation at baseline and after an acute challenge with PAF that induces most symptoms of rhinitis. Eleven healthy subjects were enrolled in the study. Plasma extravasation in the nasal airway was assessed by measuring the albumin content of nasal lavage.

RESULTS

PAF challenge caused a significant increase in concentrations of albumin in the nasal lavage fluid (from 0.59 +/- 0.13 mg dL(-1) to 2.46 +/- 0.45 mg dL(-1)) after placebo. Pretreatment with L-NAME significantly prevented the increase of albumin in the nasal lavage fluid induced by PAF as compared to placebo (from 0.53 +/- 0.11 mg dL(-1) to 1.70 +/- 0.28 mg dL(-1); P < 0.005).

CONCLUSION

Topical administration of a NO inhibitor is able to attenuate the nasal airway plasma extravasation induced by PAF, suggesting that NO release in vivo is involved in the nasal response to PAF.

Exhaled nitric oxide as a marker of adverse respiratory health effect in environmental disease

The presence of, and the possibility to assay, nitric oxide (NO) in exhaled breath of humans caused a great deal of interest in relation to understanding the physiological and pathophysiological role of this molecule. Most studies have measured exhaled NO by chemiluminescence and detection depends on the photochemical reaction between NO and ozone generated in the analyzer. Here we discuss the role of exhaled NO as a physiological method to evaluate the effect of environmental changes on lower and upper airways in healthy subjects; particularly, its potential application as non invasive marker of the effect of outdoor and indoor air pollution on the respiratory tract.

Exhaled nitric oxide after inhalation of isotonic and hypotonic solutions in healthy subjects

Airway nitric oxide (NO) homoeostasis is influenced by chemical and mechanical stimuli in humans; airway epithelium, which is an important site of NO production, is sensitive to osmotic challenge. The effect of inhaled hypotonic solutions on exhaled NO (eNO) is not known. In this study we evaluated the effect of ultrasonically nebulized distilled water (UNDW), a hypotonic indirect stimulus, on eNO levels. A total of 10 non-smoking healthy subjects were enrolled in the study. eNO was detected by chemiluminescence, and specific airway conductance (sGaw) was measured by plethysmography. Bronchial challenges with UNDW and with an isotonic solution were performed according to a double-blind experimental design. Baseline levels of eNO were 28.1+/-14.7 p.p.b. UNDW did not cause any significant change in sGaw (from 0.190+/-0.029 to 0.181+/-0.036 cm H(2)O x s(-1)). With respect to baseline values, the eNO concentration decreased significantly after inhalation of 8 or 16 ml of UNDW (from 26.0+/-13.1 to 17.2+/-8.5 and 16.6+/-7.7 p.p.b. respectively; P<0.001, n=10). After bronchial challenge with UNDW, eNO was significantly reduced in comparison with after inhalation of the isotonic solution. In five subjects, pretreatment with N(G)-nitro-L-arginine methyl ester (L-NAME), an inhibitor NO synthesis, decreased NO levels from 21.7+/-8.5 to 10.0+/-3.3 p.p.b. Subsequent inhalation of 16 ml of UNDW did not cause any further decrease in NO levels (10.1+/-3.7 p.p.b.; not significant compared with L-NAME). We conclude that inhalation of aqueous solutions decreases eNO levels in healthy subjects, and that this effect is not associated with any significant change in airway calibre. The UNDW-induced decrease in eNO is not enhanced by pretreatment with the NO synthase inhibitor L-NAME, suggesting that inhaled solutions may interfere with the airway NO pathway in humans.

Abnormalities of renal endothelin during acute exacerbation in chronic obstructive pulmonary disease

Circulating and urinary levels of endothelin (ET), an endothelium-derived vasoconstrictive and mitogenic peptide have been reported to increase in patients with chronic obstructive pulmonary disease (COPD), but the mechanisms of these abnormalities are not fully understood. Our study objectives were to evaluate pulmonary and renal ET clearance in COPD patients during an acute exacerbation. Our participants included nine consecutive patients with moderate to severe COPD without signs of right heart failure admitted for acute exacerbation and ten healthy volunteers (HV) as controls. ET was detected by radioimmunoassay in venous and arterial blood as well as in a timed urine specimen. For each subject, arterial/venous immunoreactive ET ratio (ir-ETart/ir-ETven) was evaluated as an index of its pulmonary clearance. Creatinine clearance was employed in each case to obtain a corrected renal ir-ET clearance. Glomerular filtration rate (GFR) was also assessed by dynamic(99m)Tc-diethylenetriamine pentaacetic acid renal scintigraphy in six COPD patients during acute exacerbation and at recovery. The ratio ir-ETart/ir-ETven was comparable in COPD patients (0.75+/-0.12) and in HV (0.82+/-0.09). A significant difference was found with respect to 24 h ir-ET urinary excretion between COPD patients during exacerbation as well as at recovery (respectively 142.1+/-12.8 ng/24 h and 89.0+/-15.1 ng/24 h) and HV (65.1+/-10.1 ng/24 h). ET renal clearance was higher in COPD patients than in HV (29.2+/-5.2 ml min(-1)in COPD during exacerbation; 17.5+/-3.9 ml min(-1)at recovery and 13.6+/-2.4 ml min(-1)in HV, P<0.001). GFR was 69.4+/-10.0 ml min(-1)in COPD patients during exacerbation and it significantly increased at the recovery (95.5+/-20.9 ml min(-1)P<0.001). Corrected renal clearance of the peptide was significantly correlated to GFR values during the exacerbation (r=-0.81, P<0.05). Furthermore change in renal ET production resulted associated with changes in paCO(2)(r=0.83, P<0.001) and in paO(2)(r=-0.73, P<0.05). Acute exacerbation in COPD patients causes an increase in renal ET production which is partially reversible at the recovery, in the absence of significant changes in ET-1 circulating levels. ET might contribute to the renal response to hypoxaemia and hypercapnia in COPD.

Familial outbreak of disseminated multidrug-resistant tuberculosis and meningitis

Rapidly progressive multidrug-resistant tuberculosis (MDR-TB) is well documented in human immunodeficiency virus (HIV) positive subjects, but it is not fully recognised in HIV-negative subjects in the familial environment. We report three cases of MDR-TB in three young HIV-negative subjects from the same family. All the patients showed signs of meningitis during the course of their disease, and in two cases a resistant strain of Mycobacterium tuberculosis was isolated in cerebrospinal fluid. Two of the three subjects died from neurological complications; the other was successful treated utilising both systemic and intrathecal therapy for tuberculous meningitis. By a retrospective analysis of DNA obtained from Lowenstein-Jensen cultures, the strains were confirmed as M. tuberculosis resistant to rifampicin and isoniazid, and were closely related in the two cases where specimens were available for analysis. The resistance was acquired in two patients initially infected with a susceptible strain; in the other patient, the resistance was present on the first sensitivity test for which results were available. This report demonstrates the high risk of fatality from MDR-TB for HIV-negative subjects in the absence of reliable early diagnostic and preventive tools. It also reinforces the concept that genetic susceptibility to M. tuberculosis may be an important factor in the clinical presentation and outcome of MDR-TB.

Effect of nitric oxide inhibition on nasal airway resistance after nasal allergen challenge in allergic rhinitis

BACKGROUND

Nitric oxide has been detected by chemiluminescence in the lumen of nasal airway, which is increased in nasal breathing in patients with seasonal rhinitis during a chronic exposure. The purpose of this study was to determinate the effect of a NO-synthase inhibitor NGL-arginine methyl ester (L-NAME) on nasal airway resistance (NAR) in patients with seasonal allergic rhinitis after an acute challenge to the allergen.

METHODS

Nitric oxide levels in the nose were measured by the chemiluminescence method in nine non-atopic volunteers and in seven patients with seasonal rhinitis at rest and after an acute challenge with the allergen. NAR were measured by active anterior rhinomanometry.

RESULTS

Basal nasal NO concentration in allergic rhinitis was 496.5 +/- 151.4 parts per billion (ppb). (n = 7) and it was not significantly different from levels found in the control group: 458.4 +/- 105.9 ppb (n = 9). The topical administration of L-NAME in allergic rhinitis reduced the NO concentration (338.6 +/- 99.3 ppb, P < 0.001; n = 7). In the rhinitic patients the challenge with the allergen did not modify the nasal NO levels (504.5 +/- 138.5 ppb). The application of the allergen after the pretreatment with placebo caused a significant increase in NAR (from 0.32 +/- 0.11 Pa s cm-3 to 1.01 +/- 0.12 Pa s cm-3, P < 0.001; n = 7). Pre-treatment with L-NAME did not prevent the increase in NAR induced by allergen challenge (from 0.36 +/- 0.15 Pa s cm-3 to 1.06 +/- 0.26 Pa s cm-3).

CONCLUSIONS

The results indicate that nasal administration of a NOS inhibitor L-NAME, at doses capable of decreasing nasal NO levels, has no effect on NAR and it does not prevent the NAR increase induced by an acute challenge with allergen in subjects with seasonal rhinitis.

The effect of platelet-activating factor (PAF) on nasal airway resistance in healthy subjects is not mediated by nitric oxide

BACKGROUND

The nose is an important source of nitric oxide (NO) in man, but the relevance of NO production to the response to inflammatory mediators is not clear.

METHODS

In this study, we evaluated the effect of NO inhibition on nasal airway resistance (NAR) at baseline, after an acute challenge with platelet-activating factor (PAF), a potent proinflammatory factor, and after an acute challenge with bradykinin (BK), both of which are mediators of allergic rhinitis in man. Eight healthy subjects were enrolled in the study. Nasal NO production was measured by the chemiluminescence method, and NAR was measured by active anterior rhinomanometry.

RESULTS

Basal nasal NO concentration was 500.6+/-115.6 ppb; it significantly decreased after topical administration of the NO-synthase inhibitor L-NAME, and the NO-synthase substrate L-arginine caused a recovery in NO production. The administration of L-NAME did not cause any change in basal NAR. In a double-blind fashion, we performed nasal challenge with PAF and BK after topical pretreatment with either placebo or L-NAME. After placebo pretreatment, both PAF and BK caused a significant increase in NAR (respectively, from 0.29+/-0.11 Pa s cm(-3) to 0.75+/-0.21 Pa s cm(-3), and from 0.36+/-0.18 Pa s cm(-3) to 0.71+/-0.25 Pa s cm(-3); P<0.001, n=8). Pretreatment with L-NAME did not prevent the PAF-induced increase in NAR (from 0.31+/-0.10 Pa s cm(-3) to 0.71+/-0.27 Pa s cm(-3)), whereas it prevented the BK-induced increase in NAR (from 0.33+/-0.15 Pa s cm(-3) to 0.43+/-0.16 Pa s cm(-3)).

CONCLUSIONS

Topical administration of the NO-synthase inhibitor L-NAME at doses sufficient to decrease NO nasal production does not prevent the PAF-induced increase in NAR, indicating that NO generation in vivo is not involved in the nasal response to PAF.

Detection of IgG and IgA against the mycobacterial antigen A60 in patients with extrapulmonary tuberculosis

BACKGROUND

Diagnosis of extrapulmonary tuberculosis is often difficult to establish using standard methods. Serological techniques based on detection of antibodies against mycobacterial antigen A60 have shown good sensitivity and specificity in pulmonary tuberculosis. The present study was undertaken to define the diagnostic accuracy of testing for IgG and IgA against A60 in extrapulmonary tuberculosis.

METHODS

One hundred and ninety eight subjects were studied: 42 patients with extrapulmonary tuberculosis confirmed by microbiology and/or histology, 24 subjects with healed pulmonary or extrapulmonary tuberculosis, 44 patients with a defined non-tuberculous disease, and 88 healthy volunteers (44 PPD negative and 44 PPD positive). Detection of IgG and IgA against A60 antigen was carried out by enzyme-linked immunosorbent assay. Cut off values were determined by receiver operating characteristic curves.

RESULTS

Sensitivity of the IgG test was 73.8% in extrapulmonary tuberculosis, while the specificity was 96.1%. The IgA test showed a sensitivity of 69.0% with a specificity of 93.6%. Combination of the IgG and IgA tests showed a sensitivity of 80.9% and a specificity of 92.3%. Patients with extrapulmonary tuberculosis showed significantly higher titres of both IgG and IgA against A60 than other groups.

CONCLUSIONS

Anti-A60 IgG or IgA tests are characterised by good sensitivity and specificity. The combined use of both tests allows an increase in diagnostic accuracy of extrapulmonary tuberculosis.

Characterization of platelet-activating factor acetylhydrolase in human bronchoalveolar lavage

Platelet-activating factor (PAF) is a mediator produced in human airways during acute and chronic inflammatory lung diseases. The levels of PAF are regulated by acetylhydrolase (AH), the enzyme that converts PAF to lyso-PAF. To determine whether AH was present in human bronchoalveolar lavage (BAL) fluid, BAL was obtained from normal donors (n = 18) and from adult patients with mild bronchial asthma (n = 15) or with lung fibrosis (n = 15). AH activity was consistently found in the cell-free BAL fluid. BAL-AH is an enzyme different from secretory phospholipase A2 and from plasma AH and erythrocyte AH. Furthermore, BAL-AH is inhibited as much as 95% by exposure to an oxygen radical-generating system (xanthine/xanthine oxidase). BAL-AH is significantly correlated with the number of BAL macrophages (rs = 0.63; p < 0.02). In addition, BAL macrophages release AH both spontaneously and after stimulation with tumor necrosis factor-alpha (TNF-alpha) (100 ng/ml). BAL-AH activity in patients with bronchial asthma (1.32 +/- 0.18 pmol of PAF converted to lyso-PAF/min) is significantly lower than that in normal donors (2.25 +/- 0.26 pmol/min; p < 0.001). In contrast, BAL-AH activity in patients with lung fibrosis (6.13 +/- 0.81 pmol/min) is higher than that found in normal donors (p < 0.01). The variations in BAL-AH activity in patients with bronchial asthma or lung fibrosis are due to a reduction and to an increase, respectively, in the number of active molecules rather than to changes in enzyme affinity. These data demonstrate that human BAL fluid contains an extracellular AH activity that inactivates PAF released in the airways. BAL-AH is secreted by alveolar macrophages and is highly sensitive to oxygen radical-induced damage. The secretion and inactivation of BAL-AH may influence the levels of this enzyme in BAL fluid during acute and chronic inflammatory lung diseases and, ultimately, regulate the proinflammatory activities of PAF in these disorders.

Lack of effect of nitric oxide inhibition on bronchial tone and methacholine-induced bronchoconstriction in man

The role of nitric oxide (NO) as a bronchodilator has been studied in humans with controversial results. The aim of the present study was to investigate the role of endogenous NO on bronchial tone by studying whether nitric oxide synthase (NOS) inhibition with NGnitro-L-arginine-methyl-ester (L-NAME) influences basal bronchial tone, or potentiates methacholine-induced bronchoconstriction. In a preliminary experiment in five subjects, a significant reduction in exhaled NO was found after delivering L-NAME (15 mg in saline) (from 3.9 +/- 1.2 to 2.4 +/- 1.1 nmol min-1, P < 0.05). In nine healthy non-smokers, specific airway conductance (SGAW), as a measure of airway calibre, was recorded after delivering, in a double-blind, controlled vs. placebo fashion, both nebulized L-NAME and saline, at baseline and after methacholine-induced bronchoconstriction. There was no significant difference between the baseline SGAW values before and after delivering L-NAME (0.264 +/- 0.04 and 0.267 +/- 0.05 cm H2O-1 s-1, respectively). After pre-treatment with L-NAME, SGAW values during methacholine-induced bronchoconstriction were not different in comparison to values obtained after saline inhalation. It is concluded that decreased endogenous NO does not influence bronchial tone in healthy people, nor does it modify methacholine-induced bronchoconstriction.

Urinary endothelin excretion in patients with acute lung injury

Increase in circulating levels of endothelin (ET), a potent vasoconstrictive and mitogenic endothelium-derived peptide, has been proposed as a marker of endothelium dysfunction in acute lung injury (ALI). In the present study, we have measured levels of immunoreactive ET (irET) by radioimmunoassay, in arterial (irETart), venous (irETven) and urine (irETur) samples obtained from 10 patients with ALI and 10 healthy volunteers. Arterovenous ratio, 24 h urine excretion and renal clearance of the peptide were calculated, to obtain indices of endogenous ET metabolism. The arterovenous ratio of irET was significantly higher in patients with ALI than in healthy volunteers (1.20 +/- 0.20 and 0.85 +/- 0.06, respectively; p < 0.05)). Twenty four hour urinary excretion of the peptide was increased in patients with ALI as compared to healthy volunteers (134.10 +/- 21.0 and 71.70 +/- 9.30 ng.24 h-1, respectively; p < 0.001). Renal clearance of irET was similar in patients with ALI and healthy volunteers, indicating that the increase in excretion as well as in arterovenous gradient observed in patients with ALI was related mainly to pulmonary abnormalities of peptide handling. Urinary excretion of endothelin might be a useful marker of endothelial dysfunction occurring in acute lung injury.

Endothelin abnormalities in patients with pulmonary embolism

BACKGROUND

Endothelin (ET) is an endothelium-derived multifunctional peptide involved in the local regulation of the vascular tone.

STUDY OBJECTIVES

To assess changes of endogenous ET production/excretion in the acute phase (36 h from the event) of pulmonary embolism (PE).

PARTICIPANTS

Ten patients with acute PE, nine patients with acute lung injury (ALI), and 12 healthy volunteers (HVs).

MEASUREMENTS AND RESULTS

ET was detected by radioimmunoassay in venous and arterial blood as well as in 24-h urine specimens. For each subject, arterial/venous immunoreactive ET (ir-ET) ratio was evaluated as an index of its pulmonary extraction/synthesis. Creatinine clearance was employed in each case to obtain a corrected renal ir-ET clearance. Renal ir-ET clearance was comparable in all three groups. Arterial/venous ir-ET ratio was comparable in PE and in ALI patients (1.31 +/- 0.25 vs 1.24 +/- 0.20; p = 0.7), while it was significantly higher in PE patients than in HV subjects (0.85 +/- 0.07; p = 0.0001). Accordingly, 24-h urine ir-ET excretion was higher in PE (120.50 +/- 27.36 ng/24 h) and ALI patients (135.80 +/- 21.60 ng/24 h) than in HV subjects (68.33 +/- 9.31 ng/24 h; p = 0.0001).

CONCLUSIONS

Abnormalities of ET metabolism-mainly related to increased synthesis and/or defective pulmonary handling-occur in the acute phase of PE. The relevance of this finding with respect to the pathogenesis and/or management of pulmonary thromboembolism remains to be elucidated.

Evaluation of IgA-mediated humoral immune response against the mycobacterial antigen P-90 in diagnosis of pulmonary tuberculosis

BACKGROUND

Serologic methods for diagnosis of tuberculosis have been widely investigated owing to their low cost and rapid technical execution. Sensitivity and specificity of different tests have been reported to be largely variable.

STUDY OBJECTIVES

To evaluate the IgA-mediated humoral immune response against the mycobacterial antigen P-90 as a tool for diagnosis of pulmonary tuberculosis.

PARTICIPANTS

Eighty-eight patients with microbiologically confirmed diagnosis of pulmonary tuberculosis (32 with positive sputum smears and 56 with negative sputum smears), 28 patients with a definite nontuberculous lung disease, 12 subjects with healed tuberculosis, and 47 healthy volunteers (24 purified protein derivative negative and 23 positive).

MEASUREMENTS AND RESULTS

Detection of anti-P-90 IgA was performed by enzyme-immunoassay. At a cutoff of 0.221 optical density, determined by a receiver operating characteristic curve, the overall sensitivity and specificity of the test were 70.4% and 91.9%, respectively. Patients with active tuberculosis showed significantly higher titers of anti-P-90 IgA compared with other groups (p < 0.05).

CONCLUSIONS

The evaluation of IgA-mediated humoral immune response against the antigen P-90 might constitute a useful tool for presumptive diagnosis of pulmonary tuberculosis.

Lung volumes and respiratory muscle strength in adult patients with childhood- or adult-onset growth hormone deficiency: effect of 12 months' growth hormone replacement therapy

We have described impairment of the respiratory function in adult patients with childhood-onset growth hormone (GH) deficiency. The aim of the present study was to evaluate lung volumes and respiratory muscle strength in patients diagnosed as GH deficient before and after 6 and 12 months of recombinant GH treatment. Ten adults diagnosed as GH deficient in childhood, ten adults diagnosed as GH deficient in adulthood and ten healthy subjects entered the study. For each subject, evaluation of respiratory function followed the same standard approach, consisting of respiratory muscle strength assessment, record of flow-volume curves, measurement of static lung volumes and lung diffusing capacity. Childhood-onset GH-deficient patients had a significant reduction of maximal inspiratory (p < 0.01) and maximal expiratory (p < 0.05) mouth pressures. Total lung capacity, vital capacity and functional residual capacity were significantly reduced compared to healthy subjects (p < 0.05). Conversely, residual volume and diffusing lung capacity did not show any significant change. No significant change of the ratio between the percentage forced expiratory volume in 1 s and the forced vital capacity was observed. The decrease of respiratory mouth pressures was not correlated to the decrease of lung volumes. Adult-onset GH-deficient patients had only a significant reduction of maximal expiratory pressure compared to healthy subjects (p < 0.05). After 6 months of treatment no significant differences in any of the evaluated parameters were found. After 12 months of treatment patients with childhood-onset GH deficiency show a significant improvement of lung volumes (p < 0.01) and maximal respiratory mouth pressures (p < 0.005), whereas adult-onset GH-deficient patients show a significant improvement of maximal expiratory pressure (p < 0.05). In conclusion, the results of this study showed that adult patients affected with childhood-onset GH deficiency suffer from an impairment of the ventilatory function due to a reduction of lung volumes and a decrease of respiratory pressures probably due to a reduction of respiratory muscle strength. This impairment was reversed after 12 months of treatment with recombinant GH. Conversely, adult-onset GH-deficient patients had only an impairment of the maximal expiratory pressure, probably due to respiratory muscle weakness re-established after 12 months of GH therapy.