Classification of light Yorkshire pigs at different production stages using ordinary least squares and machine learning methods

Pig homogeneity and growth are major concerns for the pig industry today. Variability in pigs' size has a strong impact on profitability as uniformity plays a key role in the overall economic value of pigs produced. This research focused on statistical methods to identify pigs at risk of growth retardation at different stages of production. Data from 125 083 Yorkshire pigs at weaning (18-28 d), 59 533 pigs at the end of the nursery period (70-82 d) and 48 862 pigs at slaughter (155-170 d) were analyzed under three different cut-points (lowest 10, 20 and 30%) to characterize light animals. Records were randomly split into 2:1 training:testing sets, and each training data set was analyzed through an ordinary least squares approach and four machine learning algorithms (decision tree, random forest, and two alternative boosting approaches). A wide range of weighting functions were applied to give increased relevance to lighter pigs. Each resulting classification norm was used to classify light pigs in the testing data set. Both sensitivity and specificity were retained to construct the receiver operating characteristic curve, and the statistical performance of each analytical approach was evaluated by the area under the curve (AUC). In all production stages and cut-points, the random forest machine learning algorithm provided the highest AUC, closely followed by boosting procedures. For weaning BW (WW), factors related to birth BW and litter size accounted for more than 75% of the important prediction factors for light pigs. BW at the end of the nursery period and slaughter BW analyses revealed a similar pattern where WW and BW at the end of the nursery period accounted for more than 40 and 50% of statistical importance among the prediction factors, respectively. Machine learning algorithms are useful tools to easily evaluate the risk factors affecting the efficiency and homogeneity in swine. Since the BW at birth and weaning are key factors, sow nutrition and feeding management during gestation and lactation, along with piglet management during lactation, are identified as important influences on pig weight variability.

The cancer stem-cell signaling network and resistance to therapy

The study of cancer stem cells (CSCs) has shown that tumors are driven by a subpopulation of self-renewing CSCs that retain the capacity to engender the various differentiated cell populations that form tumors. The characterization of CSCs has indicated that CSCs are remarkably resistant to conventional radio- and chemo-therapy. Clinically, the remaining populations of CSC are responsible for metastasis and recurrence in patients with cancer, which can lead to the disease becoming chronic and incurable. Therefore, the elimination of CSCs is an important goal of cancer treatments. Furthermore, CSCs are subject to strong regulation by the surrounding microenvironment, which also impacts tumor responses. In this review, we discuss the mechanisms by which pathways that are defective in CSCs influence ultimately therapeutic and clinical outcomes.

Effect of atmospheric mixing layer depth variations on urban air quality and daily mortality during Saharan dust outbreaks

Several epidemiological studies have shown that the outbreaks of Saharan dust over southern European countries can cause negative health effects. The reasons for the increased toxicity of airborne particles during dust storms remain to be understood although the presence of biogenic factors carried by dust particles and the interaction between dust and man-made air pollution have been hypothesized as possible causes. Intriguingly, recent findings have also demonstrated that during Saharan dust outbreaks the local man-made particulates can have stronger effects on health than during days without outbreaks. We show that the thinning of the mixing layer (ML) during Saharan dust outbreaks, systematically described here for the first time, can trigger the observed higher toxicity of ambient local air. The mixing layer height (MLH) progressively reduced with increasing intensity of dust outbreaks thus causing a progressive accumulation of anthropogenic pollutants and favouring the formation of new fine particles or specific relevant species likely from condensation of accumulated gaseous precursors on dust particles surface. Overall, statistically significant associations of MLH with all-cause daily mortality were observed. Moreover, as the MLH reduced, the risk of mortality associated with the same concentration of particulate matter increased due to the observed pollutant accumulation. The association of MLH with daily mortality and the effect of ML thinning on particle toxicity exacerbated when Saharan dust outbreaks occurred suggesting a synergic effect of atmospheric pollutants on health which was amplified during dust outbreaks. Moreover, the results may reflect higher toxicity of primary particles which predominate on low MLH days.

Clinical features and therapeutic management of subglottic stenosis in patients with Wegener's granulomatosis

The objective of the study was to evaluate the clinical features, response to treatment, and long-term outcome of subglottic stenosis (SGS) in a series of patients diagnosed as having Wegener's granulomatosis (WG) at a single institution. Subglottic stenosis developed in 6 out of 51 (11.7%) patients, in four of them in the absence of other features of active disease, and was the symptom that leads to WG diagnosis in three cases. In two cases, SGS began while the patients were receiving systemic immunosuppressive therapy for disease activity involving other sites. PR3-ANCAs were positive in four cases. An urgent tracheostomy was needed in two patients. Four patients achieved SGS clinical remission on standard treatment with glucocorticoids and cyclophosphamide, but three of them experienced repeated local relapses and required additional immunosuppressive therapy and mechanical dilations. In one case, a local relapse was successfully managed with endotracheal dilation of the stenotic segment and intralesional injection of a long-acting corticosteroid plus mechanical dilation of the stenotic segment (ILCD) without adding supplemental immunosuppressant drugs. Two patients with isolated SGS were also successfully managed with ILCD alone and did not require the institution of systemic immunosuppressive therapy. One patient underwent open surgical repair when the disease was under control. Our data suggest that Subglottic stenosis often occurs or progresses independently of other features of active WG, and that ILCD may be a safe alternative to conventional immunosuppressive therapy in patients who develop SGS in the absence of other features of active disease, allowing reducing the treatment-related toxicity.

Radioprotective-antimutagenic effects of rosemary phenolics against chromosomal damage induced in human lymphocytes by gamma-rays

The radioprotective effects of carnosic acid (CA), carnosol (COL), and rosmarinic acid (RO) against chromosomal damage induced by gamma-rays, compared with those of L-ascorbic acid (AA) and the S-containing compound dimethyl sulfoxide (DMSO), were determined by use of the micronucleus test for antimutagenic activity, evaluating the reduction in the frequency of micronuclei (MN) in cytokinesis-blocked cells of human lymphocytes before and after gamma-ray irradiation. With treatment before gamma-irradiation, the most effective compounds were, in order, CA > RO > or = COL > AA > DMSO. The radioprotective effects (antimutagenic) with treatment after gamma-irradiation were lower, and the most effective compounds were CA and COL. RO and AA presented small radioprotective activity, and the sulfur-containing compound DMSO lacked gamma-ray radioprotection capacity. Therefore, CA and COL are the only compounds that showed a significant antimutagenic activity both before and after gamma-irradiation treatments. These results are closely related to those reported by other authors on the antioxidant activity of the same compounds, and the degree of effectiveness depends on their structure. Furthermore, the results for treatments before and after gamma-ray irradiation suggest the existence of different radioprotective mechanisms in each case.

Colonización traqueal en cirugía oncológica de laringe y faringe

Surgical wound infection is one of the most frequent complications in pharyngo-laryngeal external surgery. They are usually polimicro with gram-positive, negative both aerobial and anaerobial microrganisms. The trachea is usually sterile and contamination is due to the intoduction during intubation of germs from the oropharyngeal area. A retrospective study was performed including 40 patients with pharyngo-laryngeal carcinoma. When the tracheostomy was done a culture from the internal trachea wall was obtained for micro study. Only one patient had an sterile culture from the trachea. There were 3 patients with just one microorganism and all the rest had at least two, being mixed aerobial and anaerobial flora the most frequent.

The UV Index on the Spanish Mediterranean coast

An analysis is made of measured ultraviolet erythemal solar radiation (UVER) data recorded during the year 2003 by the networks of the Catalan Weather Service and the Environment Department of Valencia (both on the Spanish Mediterranean coast). Results show a latitudinal variation at sea level, of 3-4% per degree and an increase with altitude of 10% per km. Based on these data the UV Index has been evaluated for the measuring stations. The maximum experimental value of the UV Index was around 9 during the summer, although higher values were recorded at two stations, one at the highest elevation and the other at the lowest latitude. The annual accumulated doses of irradiation on a horizontal plane have been presented as well as the evolution through the year in units of energy, Standard Erythemal Doses and Minimum Erythemal Doses according to different phototypes. Lastly, the UV Index forecast, determined with a multiple scattering radiative transfer model, has been analyzed. Total agreement or only one unit of difference between measured and modelled values was found in 94% of cloud-free cases.

[Hodgkin and Non-Hodgkin lymphomas in otorhinolaryngology]

Lymphomas of the head and neck arise in lymph nodes and extranodal areas as Waldeyer ring, nasal cavity, thyroid gland and salivary glands. Though anatomically in close proximity, lymphomas presenting at the ENT area have different clinical characteristics if they are Hodgkin or Non-Hodgkin. We included 31 patients with the diagnosis of lymphoma and diagnosed in our Department between 1999 and 2002. We studied all the different variables that differentiate Hodgkin and Non-Hodgkin's lymphoma. Both types of lymphoma usually present as a cervical mass. Non-Hodgkin lymphoma have extranodal involvement more frequently and also a more advance disease at diagnosis. It is important to include the lymphoma in the differential diagnosis of any cervical mass or ENT lesion.

Radioprotective Effects Against Chromosomal Damage Induced in Human Lymphocytes by gamma-Rays as a Function of Polymerization Grade of Grape Seed Extracts

The quantitative distribution of flavan-3-ols was determined using high-performance liquid chromatography in several grape seed extracts (GSEs). In all GSEs, polymers of four or more carbon units were the group of procyanidins present in the highest concentration, the real quantity ranging between 60% and 99.5%. In a previous paper we established a relation between antioxidant and anticlastogenic activity of GSEs. A higher grade of polymerization in GSEs allows the existence of a higher number of conjugated structures and higher antioxidant activity. The radioprotective effects of GSEs with various grades of polymerization were determined by use of the micronucleus test for anticlastogenic activity, evaluating the reduction in the frequency of micronuclei in cytokinesis-blocked cells of human lymphocytes exposed to gamma-rays. The radioprotective efficiency of GSEs was according to their grade of polymerization: GSE3 > GSE2 > GSE1 > dimethylsulfoxide. The higher antioxidant capacity and anticlastogenic activity of GSEs can be explained, structurally, by the high number of conjugated structures between the catechol groups in the B-rings and the 3-OH free groups of the polymeric polyphenolic skeleton and, in addition, by the stability of the aroxyl flavonoid radical generated in the processes.

Radioprotective effects in vivo of phenolics extracted from Olea europaea L. leaves against X-ray-induced chromosomal damage: comparative study versus several flavonoids and sulfur-containing compounds

The radioprotective effects of a polyphenolic extract of Olea europaea L. leaves (OL); the flavonoids diosmin and rutin, which are widely used as pharmaceuticals; and the sulfur-containing compounds dimethylsulfoxide (DMSO) and 6-n-propyl-2-thiouracil (PTU) were determined by using the micronucleus test for anticlastogenic activity, evaluating the reduction of the frequency of micronucleated polychromatic erythrocytes (MnPCEs) in bone marrow of mouse before and after X-ray irradiation. With treatment before X-irradiation, the most effective compounds were, in order, rutin > DMSO > OL > PTU > diosmin. These results showed, for the polyphenols studied, a linear correlation (r(2) = 0.965) between anticlastogenic activity and antioxidant capacity. The magnitude of protection with treatment after X-irradiation were lower, and the most effective compounds were, in order, OL > diosmin > rutin; DMSO and PTU lacked radioprotective activity. Therefore, OL is the only substance that showed a significant anticlastogenic activity both before and after X-ray irradiation treatments. Structurally, the free oxygen radicals and lipoperoxyradicals scavenging capacity and, consequently, the anticlastogenic activity of these polyphenolic compounds are based principally on the presence of specific functional groups, mainly catechol groups (rutin, oleuropein, hydroxytyrosol, verbascoside, luteolin), that also increase the stability of the aroxyl-polyphenol radical generated in the above processes.

Effects of several polyhydroxylated flavonoids on the growth of B16F10 melanoma and Melan-a melanocyte cell lines: influence of the sequential oxidation state of the flavonoid skeleton

The response of B16F10 melanoma and Melan-a melanocyte cell lines to treatment with five polyhydroxylated flavonoids and gallic acid, after 24 and 72 h of exposure, was determined, and the relationship between any antiproliferative effects observed and the chemical structure is discussed. After 24 h, none of the studied compounds showed significant cytotoxic activity in the B16F10 cell line, whereas compounds with an adjacent trihydroxylated substitution pattern did affect the viability of the Melan-a cell line. After 72 h of exposure, myricetin, baicalein and gallic acid significantly inhibited both B16F10 and Melan-a cell cultures, whereas luteolin and quercetin had only a moderate effect. Eriodictyol only had an effect on Melan-a cell viability, which was reduced slightly. These results suggest that the presence of a C2-C3 double bond and three adjacent hydroxyl groups in the flavonoid A- or B-rings confers greater antiproliferative activity to the flavonoid.

Globo faríngeo y reflujo faringo-laríngeo

The globus sensation is one of the most frequent complaints in a basic ENT clinic. The etiology is still unknown, although some hypotheses have been suggested such as: psychological abnormalities, esophageal and cricopharyngeal muscle disfunction and the laryngopharyngeal reflux. Laryngopharyngeal reflux is the most frequent pathology related to the globus feeling. We've tried in this study to determine the incidence of laryngopharyngeal reflux in a group of 30 patients with globus feeling. We found 26.7% of these patients with an abnormal pH monitoring test.

Effects of several flavonoids on the growth of B16F10 and SK-MEL-1 melanoma cell lines: relationship between structure and activity

Although flavonoids seem to be capable of acting at all stages of the carcinogenic process, little information is available on their action in melanoma cell lines. The aim of this study was to assess the response of B16F10 and SK-MEL-1 melanoma cell lines to treatment with six different flavonoids after 24 and 72 h of exposure and to relate the response to their structure. We then compared the findings with those for melphalan treatment. When cultures were treated for 24 h, only slight inhibition at the highest concentrations (25 and 50 microM) of tangeretin and luteolin were observed, whereas melphalan caused a dose-related inhibition of growth at all concentrations. Quercetin, hesperetin, 7,3'-dimethylhesperetin and eriodictyol did not produce any effect at 24 h on B16F10 or SK-MEL-1 cells, results which point to the low toxicity of flavonoids. After 72 h of exposure culture growth was inhibited by 7,3'-dimethylhesperetin at 50 microM, but lower concentrations had no effect. Tangeretin was the most effective of the flavonoids in inhibiting B16F10 and SK-MEL-1 cell growth, showing a clear dose-response curve after 72 h. These results suggest that the absence of the C2-C3 double bond on hydroxylated flavonoids results in a loss of effect on both the cell lines, while the higher activity of tangeretin compared with 7,3'-dimethylhesperetin suggests that the presence of at least three adjacent methoxyl groups confers a more potent antiproliferative effect.

[Usefulness of 201T1 gammagraphy in the diagnosis of carcinoma of the larynx]

For the evaluation of a patient with a laryngeal tumor we need the clinical exam and other exams as the CT scan or MRI. Those studies have a sensitivity of less than 80%. For that reason in the last years there has been a development of new techniques trying to increase the accuracy. The 201Tl SPECT is one of them although it was developed for cardiological purposes. We present our experience in 46 patients with laryngeal tumor in whom we did a 201Tl SPECT as part of the extension study. The sensitivity of the study was 81.6% in the diagnosis of the primary tumor and 46.1% for the neck adenopathies. The 201Tl SPECT can be a good method for the evaluation and detection of recurrences in patients with pharyngo-laryngeal tumor.

Partial epiglottectomy as a possible treatment for globus pharyngeus?

Globus pharyngeus is a relatively common complaint in an ear, nose, and throat consulting room and may account for 3-4% of outpatient referrals. The cause is still unknown, although a number of hypotheses have been suggested. Between 40% and 75% of the patients remain symptomatic despite any treatment regimen. Thirteen patients from a group of 124 with the diagnosis of globus pharyngeus and no response to medical treatment were treated with partial epiglottectomies. One year after the surgery all but one patient were free of symptoms. Our experience indicates that partial epiglottectomy can be a good treatment for those patients with globus pharyngeus in whom no cause is found after all studies are performed or when medical treatment fails.

[Antibiotic prophylaxis in oncologic pharyngolaryngeal surgery: ceftriaxone versus clindamycin and gentamycin]

There are many papers comparing two antibiotic protocols for the profilaxis of head and neck infections after laryngeal surgery. We present one prospective and randomised study in 60 patients comparing the efficacy of two protocols. The comparison was between ceftriaxone versus the association of clindamicyn and gentamicyn. In our database we included the risk factors for infection, the surgical approach, the duration of surgery and the patient characteristics. We observed an incidence of 28% of infection, with a 23.3% in the clindamicyn + gentamicyn group and a 33.3% in the ceftriaxone group. The differences between the two groups were not statistically significant. In this study we observed a small difference between the amount of alcohol comsuption, the effectiveness of the surgical drainage, the surgical approach and the presence of wound infection. The difference was not statistical significant due to the small group of patients. The profilaxis was adequate for the total laryngectomy and cordectomy group, with a higher incidence of wound infection in patients treated with a supraglottic laryngectomy.

Improved water solubility of neohesperidin dihydrochalcone in sweetener blends

Significant technological advantages in terms of sweetness synergy and hence cost-saving can be obtained if neohesperidin dihydrochalcone (NHDC) is used in sweetener blends with other intense or bulk sweeteners. The combination of NHDC with sodium saccharin or sodium cyclamate is an excellent method to improve the water solubility at room temperature of NHDC. In the case of NHDC-sodium saccharin, two different methods for blend preparation, a simple mixture and a cosolubilized mixture, can be used, with similar results obtained for solubility and solution stability properties. To improve temporally the water solubility of NHDC in combination with sodium cyclamate, it is absolutely necessary to prepare cosolubilized blends.

Antioxidant activity and radioprotective effects against chromosomal damage induced in vivo by X-rays of flavan-3-ols (Procyanidins) from grape seeds (Vitis vinifera): comparative study versus other phenolic and organic compounds

The quantitative distribution of several flavan-3-ols was determined using HPLC in a grape (Vitis vinifera) seed extract (GSE) of four cultivars grown in the region of Murcia. Polymer >/= C(4) units made up the largest group of procyanidins in the GSE (90.92%, expressed as HPLC % area). The antioxidant activity of GSE and other reference compounds was investigated by measuring their ability to scavenge the ABTS(*)(+) radical cation (TEAC). The most effective compounds were, in order: GSE > rutin > (+)-catechin > diosmin >/= ascorbic acid. The radioprotective effects of GSE and other reference compounds were determined by using the micronucleus test for anticlastogenic activity, any reduction of the frequency of micronucleated polychromatic erythrocytes (MnPCEs) being evaluated in the bone marrow of mouse exposed to X-rays. The most effective compounds were, in order: GSE > rutin > dimethyl sulfoxide (DMSO) > ascorbic acid > 6-n-propyl-2-thiouracil-6c (PTU) > diosmin. The higher ABTS(*)(+) scavenging capacity and anticlastogenic activity of GSE can be explained, structurally, by the high number of conjugated structures between the catechol groups in the B-rings and the 3-OH free groups of the polymeric polyphenolic skeleton and, in addition, by the stability of the aroxyl flavonoid radical generated in the above processes.

Constitutive nuclear factor-kappaB activity in human upper airway tissues and nasal epithelial cells

Respiratory epithelial cells are actively involved in the host defence and inflammatory reactions of the airways. Nuclear factor-kappaB (NF-kappaB) is a transcription factor that plays a pivotal role in many cellular responses to environmental changes. The inducible nitric oxide synthase (iNOS) isoform has been implicated in airway inflammation as well as in normal airway function. In this study, the hypothesis that NF-kappaB may be associated with iNOS expression in airway epithelium, not only in inflammatory processes but also under physiological conditions was examined. NF-kappaB deoxyribonucleic acid-binding activity was assayed by means of electrophoretic mobility shift assay (EMSA) and iNOS expression examined using immunohistochemical techniques in healthy nasal mucosa and chronically inflamed nasal polyps. Further NF-kappaB activity was assayed; by means of EMSA, in nasal epithelial cells isolated from both tissues. NF-kappaB was activated in nasal polyps, but also to the same extent in healthy nasal mucosa. Uniform iNOS expression was localized within the airway epithelium in both inflamed and noninflamed tissues. Along with iNOS expression, concomitant NF-kappaB activation was found in nasal epithelial cells obtained from both tissues and no differences were observed when nasal mucosa and nasal polyp were compared. These results suggest that constitutive nuclear factor-kappaB and concurrent inducible nitric oxide synthase expression in epithelial cells may play a physiological role in airway function.

[Nasal leishmaniasis in an HIV-positive patient]

Leishmania is currently one of the most clinically important protozoa in otorhinolaryngology. Mediterranean countries, including Spain, have endemic HIV and L. infantum. Dogs are the most important Leishmania reservoir. Leishmaniasis is transmitted basically by the bite of infected female Phlebotomus sandflies. Its clinical development depends mainly on the host's cellular immunity (TCD4+ lymphocyte count). About 400 cases of HIV-visceral leishmaniasis have been reported in Spain. However, exclusively cutaneous presentation of HIV-leishmaniasis coinfection has been observed in only 2-3% of cases. We report the case of a female HIV+ patient who developed cutaneous leishmaniasis of the nasal vestibule by L. infantum. The patient was treated satisfactorily with a combination of parenteral Pentostam (sodium stilbogluconate) and periodic intralesional injections of Pentostam. The patient was included in a secondary prophylaxis protocol for visceral leishmaniasis with a monthly dose of Glucantime (meglumine antimoniate) for life.

[Second primary tumors in patients with laryngeal neoplasms]

A cohort epidemiologic study of second primary tumours appeared in patients diagnosed of laryngeal neoplasms, between years 1988 and 1990, and a follow-up term of 5 years, is presented. An statistical analysis of several data to define a possible high risk group for developing primary tumours was performed for all patients.

[Nitric oxide synthase activity in nasal mucosa]

Nitric oxide (NO) plays an important regulatory role in airway function and seems to be implicated in the pathophysiology of several airway diseases. We studied the presence of NO synthase activity in human nasal mucosa and nasal polyp tissues obtained from patients undergoing septoplasty or polypectomy, respectively. NO synthase activity was quantified in tissue homogenates using citrulline release assay and was located in tissue sections using NADPH-diaphorase histochemistry. The results indicated that nasal polyps contain higher levels of total NO synthase activity than nasal mucosa tissue. In addition, nasal polyps contained mainly inducible NO synthase activity whereas all NO synthase activity detected in the nasal mucosa was in constitutive form. In both cases, NO synthase activity was localized in epithelial cells. In view of these results, we conclude that NO may be an important inflammatory mediator in the respiratory system and that the epithelium may be a source of NO production.

[Comparative study of 2 antibiotic prophylactic protocols in oncologic surgery of the pharynx and larynx]

The use of antibiotic prophylaxis in oncological pharyngeal and laryngeal surgery has reduced the risk of postoperative wound infection, which decreases morbidity and health-care costs. We report the results of a prospective randomized study in our hospital comparing the effectiveness of two antibiotic protocols, amoxicillin-clavulanate and clindamycin plus gentamicin, both given for 24 hours, in patients who underwent clean-contaminated oncological surgery of the pharynx or larynx.

Comparison of models used for UV index calculations

Eighteen radiative transfer models in use for calculation of UV index are compared with respect to their results for more that 100 cloud-free atmospheres, which describe present, possible future and extreme conditions. The comparison includes six multiple-scattering spectral models, eight fast spectral models and four empirical models. Averages of the results of the six participating multiple-scattering spectral models are taken as a basis for assessment. The agreement among the multiple-scattering models is within +/- 0.5 UV index values for more than 80% of chosen atmospheric parameters. The fast spectral models have very different agreement, between +/- 1 and up to 12 UV index values. The results of the empirical models agree reasonably well with the reference models but only for the atmospheres for which they have been developed. The data to describe the atmospheric conditions, which are used for the comparison, together with the individual results of all participating models and model descriptions are available on the Internet: http://www.meteo.physik.uni-muenchen.de/++ +strahlung/cost/.

[Omeprazole: a new treatment for paranasal sinus polyps in Widal syndrome. Preliminary study]

A preliminary report is made of the potential therapeutic effect of omeprazol in reducing nasosinusal polyps. This study is based on the empirical observation of nasal airflow improvement in patients suffering from nasosinusal polyposis after administering omeprazol. Different phases of the study suggested that patients with Widal's syndrome benefited the most. Based on the results of this study, we have undertaken a randomized, parallel, double-blind, placebo-controlled clinical trial.

[Mucoceles. Review of reported cases in the last 15 years]

The AA. present a retrospective study of all instances diagnosed as mucoceles in the last 15 years (1978-1993) at General University Hospital, Valle de Hebrón. Age of occurrence and sex, foregoing pathologic history, clinical picture, diagnostic tests, treatment and subsequent course of the condition are duly considered and appraised. Our attempt has been to stablish a diagnostic clinical pattern of these conditions, which generally are uncovered through its complications.

[Pulmonary and laryngeal tuberculosis. Study of 26 patients]

A description is reported of tuberculosis cases (TBC) with symptomatic laryngeal involvement diagnosed and treated from 1982 to 1994. Twenty-six out of 2,800 (0.9%) patients diagnosed with TBC had laryngeal symptoms. Twelve patients underwent laryngeal biopsy and the disease was diagnosed in 11; the remaining 15 patients were diagnosed on the basis of the typical lesions at laryngoscopy and resolution with specific therapy; in all of them there was a pulmonary TBC associated. The mean time of clinical laryngeal symptoms was five months and the most common symptom was dysphonia. There were factors which increased the risk for TBC in 16 patients (61.5%), alcoholism being the most common symptom in 10 (38%) patients. X-Ray examination revealed bilateral infiltrates or cavitation in 81% of patients. Sputum examination for acid-fast bacilli was positive in 15 (58%) and culture for Mycobacterium tuberculosis was positive in all of them. All patients adhered correctly to the therapeutic regimen and the clinical course was towards healing: no patient had laryngeal carcinoma after one year of follow-up. The incidence of symptomatic laryngeal TBC in our environment is low and usually presents in patients with risk factors, particularly alcoholism, with a long evolution of the disease and associated with extensive pulmonary TBC. The coexistence with laryngeal carcinoma is exceptional; therefore, when the association of laryngeal symptoms and active pulmonary TBC is present it is reasonable to reserve the laryngeal biopsy for those patients with lymph node enlargement, risk factors, or when symptoms persist after a correct therapeutic regime has been instituted.

Differential activity of nitric oxide synthase in human nasal mucosa and polyps

Nitric oxide (NO) plays an important regulatory role in airway function and seems to be implicated in the pathophysiology of several airway diseases. To better understand the involvement of NO in the upper airways, we examined the presence of nitric oxide synthase (NOS) activity in human nasal mucosa and nasal polyp tissues. Nasal mucosa was obtained from seven patients undergoing septoplasty, and nasal polyps came from nine patients following polypectomy. NOS activity was quantified in tissue homogenates using the citrulline release assay and localized in tissue sections using reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry. The results showed that nasal polyps (n = 9) contained higher levels of total NOS activity (mean +/- SD 5.94 +/- 5.71, range 1.29-18.0 pmol.min-1.mg protein) than nasal mucosa tissues (n = 7) (0.28 +/- 0.22, range 0.01-0.57 pmol.min-1.mg protein). In addition, nasal polyps mainly contained inducible NOS activity (4.67 +/- 4.57, range 1.23-15.5 pmol.min-1.mg protein) whereas in nasal mucosa all NOS activity detected was in constitutive form. In both cases, NOS activity was localized in the epithelial cells. Since NO synthase is induced in inflamed upper airways, we conclude that NO may be an important inflammatory mediator in the respiratory system and that the epithelium may be a source of NO production in the human upper airways.

Hearing and diabetes

The results of the audiological evaluation of 47 diabetics are presented. The patients were divided into two groups: A (17/47), type I early diabetics, and B (30/47), type I chronic diabetics. The evaluation included puretone audiometry, high-frequency audiometry and auditory brainstem response. There was a control group consisting of 30 healthy subjects. In group 1 the audiological assessment was normal in all cases. In group 2 hearing loss was found in 30% of cases (9/30). Hearing loss was significantly correlated with age (p = 0.0019) and duration of diabetes (p = 0.0143), but not with diabetic microangiopathy (p = 0.1506). The authors conclude that hearing loss is not a usual feature in diabetic patients. When present, hearing loss should be attributed to the effect of diabetes on the age-related physiological impairment of the inner ear. The pathogenic mechanisms remain obscure.