Neumomediastino espontáneo en contexto de afectación por COVID-19 / Spontaneous pneumomediastinum in the context of covid-19 involvement

El neumomediastino espontáneo en contexto de COVID-19 es una afectación rara y producida por aumento de la presión intratorácica sobre daño alveolar difuso en los casos de afectación grave. En principio se considera un cuadro autolimitado que responde favorablemente a medidas terapéuticas conservadoras. No obstante, se recomienda su vigilancia estrecha debido a sus posibilidades de complicación cardiovascular y respiratoria (AU)

Spontaneous pneumomediastinum in the context of COVID-19 is a rare condition caused by increased intrathoracic pressure on diffuse alveolar damage in cases of severe disease. In principle, it is considered a self-limited condition that responds favorably to conservative therapeutic measures. However, close monitoring is recommended due to its potential for cardiovascular and respiratory complications (AU)

Respiratory disease in Niemann-Pick type C2 is caused by pulmonary alveolar proteinosis.

Niemann-Pick diseases are hereditary neurovisceral lysosomal lipid storage disorders, of which the rare type C2 almost uniformly presents with respiratory distress in early infancy. In the patient presented here, the NPC2 exon 4 frameshift mutation c.408_409delAA caused reduced NPC2 protein levels in serum and lung lavage fluid and the synthesis of an aberrant, larger sized protein of around 28 kDa. Protein expression was strongly reduced also in alveolar macrophages. The infant developed failure to thrive and tachypnea. Lung lavage, computer tomography, and histology showed typical signs of pulmonary alveolar proteinosis with an abnormal intraalveolar accumulation of surfactant as well as macrophages. An NPC2-hypomorph animal model also showed pulmonary alveolar proteinosis and accumulation of macrophages in the lung, liver, and spleen long before the mice died. Due to the elevation of cholesterol, the surfactant had an abnormal composition and function. Despite the removal of large amounts of surfactant from the lungs by therapeutic lung lavages, this treatment was only temporarily successful and the infant died of respiratory failure. Our data indicate that respiratory distress in NPC2 disease is associated with a loss of normal NPC2 protein expression in alveolar macrophages and the accumulation of functionally inactive surfactant rich in cholesterol.

Helicobacter pylori "test-and-scope" strategy for dyspeptic patients. Is it useful and safe?

AIM: To evaluate outcome of test-and-scope strategy using 13C-urea breath test, Helicobacter pylori IgG serology, and CagA serology. PATIENTS AND METHODS: A series of 100 dyspeptic patients were studied. Biopsies were obtained for histology and rapid urease test (gold standard). Serum samples were obtained for Helicobacter pylori IgG and CagA serology, and 13C-urea breath test was carried out. RESULTS: If endoscopy had not been performed in Helicobacter pylori patients based on 13C-urea breath test, <45 years, without alarm symptoms, and without non-steroidal anti-inflammatory drug use, 15% of endoscopies would have been saved, and one gastric ulcer and two oesophagitis would have been missed. Based on Helicobacter pylori IgG serology, 21% of endoscopies would have been saved. Finally, if endoscopy had been performed only in CagA+ patients, 31% of endoscopies would have been saved, missing one gastric ulcer and two cases of oesophagitis. CONCLUSIONS: In our geographical area, the test-and-scope strategy based on 13C-urea breath test or Helicobacter pylori IgG serology would have saved only 15-20% of endoscopies. Although some relevant pathology would have been missed, it is not of a malignant type. 13C-urea breath test is the preferred non-invasive method to be used in this strategy, while Helicobacter pylori IgG serology is of limited value due to its low accuracy. With the use of CagA serology a larger number of unnecessary endoscopic examinations can be avoided.

["Rapid" serology for the diagnosis of Helicobacter pylori infection. Evaluation of its accuracy compared with a gold-standard and its concordance with "classic" serology]. / Serología "rápida" para el diagnóstico de infección por H. pylori. Estudio de su validez frente a un patrón de referencia y de su concordancia con la serología "clásica".

AIM: To prospectively evaluate the validity of a rapid office-based diagnostic serological test (using capillary blood) in our population, taking as reference a combination of standard diagnostic methods, as well as to compare the results of this technique with those of "classic" serological tests (using venous blood). PATIENTS AND METHODS: We prospectively studied 39 consecutive patients with symptoms of the upper digestive tract who had undergone oral gastroscopy. Gastric biopsies were taken for histology and rapid urease testing, and a 13C-urea breath test was performed. An enzyme-linked immunoassay that detects IgG antibodies against Helicobacter pylori was used as a "classic" serological test and the commercial kit FlexPack HP was used as a "rapid" serological test. The endoscopist, the pathologist and those responsible for reading the rapid urease test, the 13C-urea breath test and both serological tests did not know the results of the other diagnostic methods. Patients were considered H. pylori positive when at least two of the three validated tests (rapid urease test, histology, and 13C-urea breath test) revealed infection and were considered free of infection when all tests were negative. RESULTS: Thirty-nine patients were studied. Thirty-eight per cent were male (mean age 48 +/- 15 years). The prevalence of H. pylori infection detected by the gold standard was 69.2%. The sensitivity and specificity of the "classic" serological test was 96% 95% (CI: 79-99) and 91% (59-100). "Rapid" serological testing was positive in nine patients, negative in 28 and indeterminate in two. A single digital puncture was sufficient in 80% of the patients, 15% needed two and 5% needed three. Most patients (77%) had no preference for either type of serological test while 20.5% preferred digital puncture and 2.5% venous puncture. The sensitivity, specificity, positive predictive value and negative predictive value were 31% (16-50), 91% (59-100), 89% (52-100) and 36% (19-56) respectively. Sensitivity was unaffected by age but specificity was lower in patients older than 40 years (89% vs. 100%; McNemar's test: 8; p < 0.01). Kappa's coefficient between the "classic" and the "rapid" serological tests was 0.16 (SE 0.1) and McNemar's test was 12.2 (p < 0.001), which indicates that the prevalence of infection diagnosed by both methods was not homogeneous. CONCLUSION: The "rapid" office-based serological test used in our study is of insufficient diagnostic accuracy to be used in clinical practice to identify H. pylori infection.

[Antibodies against Helicobacter pylori in saliva. Study of their validity versus breath test and its agreement with serology]. / Anticuerpos frente a Helicobacter pylori en saliva. Estudio de su validez frente a la prueba del aliento y de su concordancia con la serología.

OBJECTIVES: To evaluate prospectively the validity of a new diagnostic method based on a saliva sample, taking as reference the breath test with 13C-marked urea, and to compare the results of this technique with another indirect method based on the detection of antibodies, "classical" serology using venous blood. METHODS: 48 individuals, 24 healthy volunteers and 24 consecutive patients with gastro-duodenal ulcer disease, were studied prospectively. Treatment during the previous month with gastro-erosive medication, antibiotics, proton-pump inhibitors or bismuth-derived drugs, prior treatment to eradicate H. pylori, gastric surgery and the presence of linked illnesses, were all considered criteria of exclusion from the study. For the diagnostic test in saliva a commercial enzyme-linked immunosorbent assay (ELISA, trademark Helisal) was used; and for blood serology, another commercial ELISA (Helico-G). The staff responsible for reading the saliva, serology and breath tests did not know the result of the other diagnostic methods. The result of the breath test with 13C-urea (TAU-kit) was taken as the reference standard for H. pylori infection. RESULTS: The mean age of the healthy volunteers was 23 +/- 0.7 years; and of ulcer patients, 55 +/- 18. The prevalence of H. pylori infection, valued by the gold standard, was 79.2% in the ulcer patients and 54% in the volunteers. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of the saliva test in the ulcer patients were, respectively: 100% (95% CI, 79-99), 60% (17-93), 90% (68-98), 100% (31-97) and 92% (71-98). In the volunteers these figures were: 46% (20-74), 73% (39-93), 67% (31-91), 53% (27-78) and 58% (37-77). The serology results were better, with 100% sensitivity in both groups and outstanding diagnostic accuracy (92% and 96% for ulcer patients and volunteers, respectively). Concordance between serology and the saliva test in ulcer patients was perfect (kappa, 1). However, in asymptomatic individuals concordance was deficient (kappa, 0.28), and the prevalence of infection diagnosed with the two tests was not homogeneous (McNemar, 2.8; p < 0.05). CONCLUSION: The diagnostic test for H. pylori infection in saliva is lacking in diagnostic accuracy in healthy individuals, which indicates that it cannot be used for screening infection in the asymptomatic population. The technique is more valuable in ulcer patients, although it does not reach the specificity desirable. For these reasons, the saliva test evaluated in this study cannot be recommended for diagnosis of H. pylori infection.

The pheromonal restoration of cyclic activity in young estrogenized persistent estrus female rats is a vomeronasal effect.

Eight sham-operated (SO) and six vomeronasalectomized (VMNX) young adult female rats were used to demonstrate the participation of the vomeronasal organ (VNO) in the pheromonal restoration of cyclic activity (PRCA). All rats were normal four-day cycling before and after surgery and they received a single subcutaneous injection of 2 mg of estradiol benzoate (EB) to induce an anovulatory persistent vaginal estrus. Fifteen days after EB injection, they were treated by spraying in the nostrils, every 10 min for one hour on only one day, 50 muL of urine from young fertile males. SO rats showed PRCA in the following days, while VMNX did not. These results support the VNO as the receptor of the male urinary pheromone (or pheromones) responsible for PRCA, demonstrating that it is possible to improve the function of aging ovaries acting with an exteroceptive stimulus.

Hormonal pattern of the pheromonal restoration of cyclic activity in aging irregularly cycling and persistent-estrus female rats.

This study reports the hormonal pattern of pheromonal restoration of cyclic activity (PRCA) in irregularly cycling (IC) and in anovulatory persistent-estrus (PE) aging female middle-aged Wistar rats. Hypothalamic content of LHRH and plasma levels of LH, FSH, estradiol (E2), and progesterone (P) were measured by RIA methods, and prolactin (PRL) was examined by ELISA in 1) normal four-day cycling rats, 2) saline-treated IC and PE rats, and 3) IC and PE rats treated with sprays of male urine (50 microliters every 10 min for 1 h on only one day, at a distance of 1 cm from the nostrils). Group 1 showed low levels of LHRH and high levels of LH, FSH, E2, P, and PRL in the afternoon of proestrus (PR). In group 2, the pattern was not cyclical and the levels of the hormones were higher than basal for the cyclic rats, except for P, which was lower. Group 3 showed a depletion of the hypothalamic LHRH and an increase in plasma LH, FSH, E2, Pm, and PRL. FSH, E2, and P showed the strongest rise, leading to an elevated ratio of FSH to LH. Four-day estrous cycles reappeared in urine-treated rats on the succeeding days. The cyclic behavior of the PRCA hormones was, qualitatively, the same as in the normally cycling rats. According to the results, the origin of the PRCA effect is an olfactory input to the hypophysiotropic area of the hypothalamus.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of the postnatal administration of tumor necrosis factor plus interferon-alpha 2b on the development of ethyl-nitrosourea-induced brain tumors in rats.

Using the experimental model of brain tumors induced by ethyl-nitrosourea (ENU), interferon-alpha 2b and human recombinant tumor necrosis factor-alpha (TNF) have been administered to Wistar rats between 100 and 130 days of life (one injection each week, by intraperitoneal route, of 100 micrograms of TNF and 10(4) IU of interferon-alpha 2b, in a total volume of 1 ml per injection). The results obtained suggest, that at this time, this association achieves a reduction in the number of so-called 'malignant schwannomas', but it does not influence the time of appearance nor the number of so-called 'malignant schwannomas', but it does not influence the time of appearance nor the number of so-called 'oligodendroglioma-like tumors'. On the basis of previous observations about cytokine modulation of these ENU-induced neoplasms, a different course of time for obtaining a postnatal biomodulation of both type of tumors is suggested.

Pheromonal male-induced diestrus and cyclicity in aging intact and young estrogenized female rats.

Reproductive aging in female rats is characterized by irregular estrous cycles, repeated pseudopregnancies, persistent estrus, and a decline in fertility. The persistently estrous rats do not ovulate or show cyclic increases of LH despite continued ovarian follicular development. These rats ovulate after mating with fertile males. On the other hand, a single injection of estradiol to young female cyclic rats causes persistent anovulatory estrus similar to that of aging rats, which has suggested that young cyclic estrogen-primed females may be a model for the study of reproductive senescence. We attempted to determine whether the male factor that elicits ovulation in aging females is pheromonal in nature. The effect of such a pheromonal factor on the persistent estrus of young estrogenized females was also tested. We observed the estrous cycle of aging (7-13-mo-old) and young estrogenized female rats daily. Nasal spraying of urine obtained from young adult male rats induced diestrus and regular cyclicity in both aging intact and young estrogenized female rats, probably because of due to pheromones contained in male urine. This fact suggests an important role of chemosensory communication in prolongation of the period with normal estrous cycles in the female's reproductive life.

Determination of protein in polysaccharide-antibody complexes.

We describe a simple and sensitive method for determining antibody protein complexed with polysaccharide using binding of Amido-black to antigen-antibody complexes and bovine serum albumin as protein standard. The method, which is a modification of the method used for the determination of total nitrogen or the protein concentration in milk, has shown a consistent quantitative relationship with the Lowry procedure and has been developed for its particular application to serological precipitates.