Reticencia vacunal: análisis del discurso de madres y padres con rechazo total o parcial a las vacunas

Objective

To analyse and understand vaccination hesitancy discourses, particularly those of people who have decided not to vaccinate their sons and daughters.

Direct effect of acute metabolic and respiratory acidosis on parathyroid hormone secretion in the dog.

Because both metabolic (Met Acid) and respiratory acidosis (Resp Acid) have diverse effects on mineral metabolism, it has been difficult to establish whether acidosis directly affects parathyroid hormone (PTH) secretion. Our goal was to determine whether acute Met Acid and Resp Acid directly affected PTH secretion. Three groups of dogs were studied: control, acute Met Acid induced by HCl infusion, and acute Resp Acid induced by hypoventilation. EDTA was infused to prevent acidosis-induced increases in ionized calcium, but more EDTA was needed in Met Acid than in Resp Acid. The PTH response to EDTA-induced hypocalcemia was evaluated also. Magnesium needed to be infused in groups receiving EDTA to prevent hypomagnesemia. The half-life of intact PTH (iPTH) was determined during hypocalcemia when PTH was measured after parathyroidectomy. During normocalcemia, PTH values were greater (p < 0.05) in Met Acid (92 +/- 19 pg/ml) and Resp Acid (77 +/- 22 pg/ml) than in controls (27 +/- 5 pg/ml); the respective pH values were 7.23 +/- 0.01, 7.24 +/- 0.01, and 7.39 +/- 0.02. The maximal PTH response to hypocalcemia was greater (p < 0.05) in Met Acid (443 +/- 54 pg/ml) than in Resp Acid (267 +/- 37 pg/ml) and controls (262 +/- 48 pg/ml). The half-life of PTH was greater (p < 0.05) in Met Acid than in controls, but the PTH secretion rate also was greater (p < 0.05) in Met Acid than in the other two groups. In conclusion, (1) both acute Met Acid and Resp Acid increase PTH secretion when the ionized calcium concentration is normal; (2) acute Met Acid may increase the bone efflux of calcium more than Resp Acid; (3) acute Met Acid acts as a secretogogue for PTH secretion because it enhances the maximal PTH response to hypocalcemia.     

Phase I study of high-dose cytosine arabinoside and etoposide in patients with advanced malignancies

Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m² as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m²×2 doses of ara-C and 50 mg/m² of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182     

Comparison of ThinPrep versus conventional smear cytopreparatory techniques for fine-needle aspiration specimens of head and neck masses.

OBJECTIVES: Diagnostic accuracy of the ThinPrep process (Cytyc, Boxborough, MA) was compared with that of conventional (smear) cytopreparation for fine-needle aspiration (FNA) of head and neck masses. METHODS: In a prospective, randomized, single-blinded study, 209 patients served as their own controls and underwent 236 FNAs using ThinPrep and conventional (smear) cytopreparatory techniques. RESULTS: ThinPrep produced less air-drying artifact and less mechanical distortion than the conventional method. The conventional technique was diagnostic in 63% of samples; the ThinPrep technique was diagnostic in 55% of samples. When all results were combined, pathologists subjectively preferred the conventional technique but accepted use of ThinPrep as the only cytopreparatory technique for most head and neck masses. CONCLUSIONS: For adequately experienced cytopathologists, ThinPrep is acceptable for FNA of salivary masses, neck cysts, metastatic lymph nodes, and thyroid lesions. Conventional smear technique should be used for FNA of nonmetastatic lymphoid lesions. Use of ThinPrep can complement use of the conventional (smear) cytopreparatory technique when aspirate is nondiagnostic or bloody, when the patient has a blood-borne infectious disease, when the clinician is inexperienced, or when aspirate has entered the syringe.     

Electrophysiologic evaluation of Emery-Dreifuss muscular dystrophy. A single fiber and quantitative EMG study

A 16-year-old boy, the only affected member of the family, noticed early onset contracture of the elbows, and developed slowly progressive humeroperoneal weakness and atrophy, and bilateral equinus. The severe restriction of the forward flexion of the neck and thoracolumbar spine, resembled a rigid spine syndrome. An electrocardiogram showed atrioventricular conduction abnormalities. Muscle biopsy was consistent with mild myopathy. The overall conventional findings of a detailed electromyographic study in the limbs and erector trunci muscles, as well as the results of conduction velocity, automatic analysis of the voluntary pattern and single fiber electromyography studies were consistent with myopathy, although some atypical findings were found. The controversy about neurogenic and myopathic features in Emery-Dreifuss disease is discussed. The unspecific value of the flexion limitation of the spine, and the uncertain nosological position of the rigid spine syndrome are also commented.     

Modified cervical laminoforaminotomy based on anatomic landmarks reduces need for bony removal.

We describe a modified keyhole laminoforaminotomy (LF) using anatomic landmarks on the posterior aspect of the cervical vertebral body to decompress the intervertebral foramen with minimal bone removal. Twenty-four procedures were performed at C3-4, C4-5, and C5-6; 12 at C6-7; and 3 at C7-Tl. Facets and laminae structures were identified based on relative surgical perspectives. Bony resection was limited as follows: 1) inferior limit; inferior border of the superior facet; 2) superior limit, superior border of the superior facet; 3) lateral limit, a vertical line linking the junction of the lamina-facet to the lateral end of the superior limit; and 4) lateral aspect of the dural sac. Fluoroscopy was used to confirm that the intervertebral space was reached. The amount of bony removal was quantified for the superior and inferior laminae and facets. The length of the exposed nerve root was measured. The intervertebral foramen was exposed and the intervertebral disc reached in all specimens. Fluoroscopy showed that the center of the exposure remained at the same height with the intervertebral space. The mean length of the nerve root was 4.6 mm; the mean percentage of bony resection was 21.8%, 7.5%, 11.3%, and 11.5% for the superior and inferior laminae and facets, respectively. Opening the intervertebral foramen posteriorly consistently exposed sufficient nerve root length and allowed access to the intervertebral disc. The technique offers the most direct and safest method of decompressing the intervertebral foramen while minimizing bony resection. This simple surgical procedure may help reduce postoperative morbidity.