Characteristics of pollinosis caused by Betula in patients from Ourense (Galicia, Spain).

A retrospective study was performed to describe the features of the pollinosis caused by Betula in the area of Ourense, Spain. The pollen count was carried out with a Lanzoni volumetric Hirts spore trap (1993-2000). The Betula pollen represented 5% over the annual total (annual mean quantity: 965 grains). It was present in the air from March to mid-May. The highest peaks took place in April (maximum values mean: 131 grains/m3). The medical records of 222 patients (mean age 25.66 years) diagnosed with pollinosis (1998-2000), who lived at less than 30 km. from the spore trap, were reviewed. In all of them, the skin-prick test (SPT) was carried out with pollen allergens. The percentages of positive SPT were: Lolium perenne, 91.89% (16.6% monosensitized); Plantago lanceolata, 71.17% (1.26% monosensitized); Betula alba, 41.89% (10.75% monosensitized); Platanus hybrida, 34.95%; Olea europea, 10.36%; and Parietaria judaica, 6.3%. The mean age of Betula monosensitized patients was 44.7 years. The majority of them had symptoms in March-April, 40% had asthma symptoms, 80% had lived in Central Europe, and 30% of them presented an oral allergy syndrome to fruits. There were 41.93% of the patients with positive SPT to Betula pollen who had asthma symptoms, in comparison with 23.25% of the patients with negative SPT to Betula (p = 0.0034). There were 20.28% of the patients with positive SPT to Betula pollen, who had lived in Central Europe, in comparison with 4.27% of the patients with negative SPT to Betula, p: 0.00049. The relative risk of sensitization was 2.05. CONCLUSIONS: Betula pollen was the second cause of clinical pollinosis in our patients, after grass, being responsible of the symptoms in the early spring, in a small number of the patients in their forties. The presence of asthma was higher in Betula sensitized patients, and the residence in Central Europe was a sensitization risk factor.     

Photochromic intensification of diaminobenzidine reaction product in the presence of tetrazolium salts: applications for intracellular labelling and immunohistochemistry.

The diaminobenzidine (DAB) reaction product can be greatly intensified by incubating the reacted tissue in either nitro blue tetrazolium or tetranitro blue tetrazolium and then exposing the tissue to strong light. Epi-illumination through a microscope objective enables the photochromic intensification to be carried out under direct visual control, with optimal intensification taking only 10-30 s through a 20x objective. Alternatively, the whole preparation can be intensified in a few minutes by passing it back and forth under a fibre light guide. The method can be used to intensify cells that have been labelled either by immunoperoxidase techniques or with intracellular tracers such as horseradish peroxidase and neurobiotin.     

The usefulness of transesophageal echocardiography in the diagnosis of pulmonary thromboembolism]

Three cases with suspected pulmonary artery embolism are presented, in which transesophageal echocardiography showed a mass in the right pulmonary artery consistent with thrombus. The relevant diagnostic contributions of transesophageal echocardiography are discussed.     

Carcinoma of the body and tail of the pancreas.

Recently, several institutions have reported improved results in the treatment of patients with carcinoma of the head of the pancreas. In an attempt to determine whether similar trends could be demonstrated for patients with carcinoma of the body and tail of the pancreas, the records of all 113 patients with an adenocarcinoma of the body or tail of the pancreas treated at The Johns Hopkins Hospital between 1972 and 1989 were reviewed. The patients were divided into two groups: those diagnosed between 1972 and 1982 (41 patients) and those between 1983 and 1989 (72 patients). No significant differences in tumor stage were observed between the two groups. The proportion of patients who underwent surgery decreased from 68% to 47% (p = 0.02). The number of patients who had bypass operations (15% versus 17%) or pancreatic resection (5% versus 10%) was similar in the two groups, but the proportion of patients who underwent exploratory laparotomy with biopsy only decreased from 49% to 21% (p = 0.002). The postoperative 30-day mortality (7% versus 3%), postoperative morbidity (18% versus 21%), median survival (4 months versus 3 months), and the 1-year survival (8% versus 9%) did not differ significantly between the two groups. One patient survived for 6 years after resection, and another patient is still alive 3 years after resection. Thus, unlike adenocarcinoma of the head of the pancreas, it appears that treatment results for patients with adenocarcinoma of the body or tail of the pancreas have not improved in recent years, the only change being a decreased need for exploratory laparotomy with biopsy only.     

Microtubule-associated protein tau is required for axonal neurite elaboration by neuroblastoma cells.

NB2a/d1 neuroblastoma cells constitutively express multiple isoforms of the microtubule-associated protein tau and incorporate this protein into the axonal neurites elaborated during serum deprivation. To examine whether or not tau played an essential role in axonal outgrowth, cells cultured in serum-free medium were treated at 24 h intervals with antisense- and sense-oriented cDNA oligonucleotides (25 or 36 mers that span or are upstream of tau initiation codon) and were simultaneously serum deprived. Oligonucleotide uptake was confirmed by determination of intracellular levels of radiolabeled oligonucleotides. Treatment for 48 h with tau antisense oligonucleotides reversibly inhibited the expression of tau and the number of neurite-bearing cells compared with treatment with sense oligonucleotides. By contrast, tubulin expression was not affected. When cells were treated with antisense oligonucleotide simultaneously with serum deprivation, the initial outgrowth of neurites was unaffected, but continued neurite elongation was prevented. By contrast, neurite outgrowth at 4 h was inhibited when cells were pretreated with tau antisense 24 h before serum deprivation. Furthermore, intracellular delivery of anti-tau antiserum prevented neurite outgrowth and, in cells that had previously been deprived of serum for 24 h, induced retraction of existing neurites. These findings indicate that both the initiation and the continued outgrowth of neurites are dependent on tau and that pre-existing cytoplasmic pools of tau can mediate initial neuritogenesis.