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The aim of this study was to evaluate whether 99Tcm-tetrofosmin is a suitable agent for parathyroid scintigraphy. Ten patients with hyperparathyroidism and two normal subjects underwent parathyroid scintigraphy with both 99Tcm-tetrofosmin and 201TI. Thyroid image subtraction was performed with 99Tcm-pertechnetate. In the 10 patients with hyperparathyroidism, the scintigraphic results were compared with the surgical findings, which showed seven parathyroid adenomas, two parathyroid adenomas with a co-existing thyroid adenoma, and one thyroid carcinoma. Both 99Tcm-tetrofosmin and 201T1 revealed eight true-positive results, one false-negative results and one false-positive result, with concordance in 8 of 10 patients. The image quality with 99Tcm-tetrofosmin of both the raw and 99Tcm-pertechnetate subtracted images was always superior compared with that with 201T1. On the basis of the diagnostic results and the favourable dosimetric characteristics, we conclude that 99Tcm-tetrofosmin is a suitable agent for parathyroid scintigraphy.

Monoclonal antibodies have been raised against the porcine LH receptor and have allowed to clone the corresponding messenger RNA from testicular cells. The stricture of the LH receptor has been determined. It shows similarities but also differences with other G protein coupled receptors. Specially a large extracellular domain is specific of that new family of receptors. Variant forms of the LH receptor generated by alternative splicing and lacking transmembrane domain have been isolated. Immunochemical and immunocytochemical studies have been performed. Three different forms of the LH receptor are physiologically expressed: a mature 85kDa transmembrane species, a 68 kDa high mannose containing species corresponding to a precursor which accumulates inside the cells, and truncated 45-48kDa molecular weight species corresponding to the variant messenger RNAs identified during the cloning of the receptor. A novel zonation of the ovary has been described by immunocytochemical studies. Cross hybridization with the LH receptor clone allowed to isolate the related TSH receptor from human thyroid tissue. The human LH and FSH receptor genes have been localized to chromosome 2p21 and the TSH receptor gene to chromosome 14q31. The genes are very large (60 kbp) and have introns only within the 5' part encoding the extracellular domain of the receptor. Immunoelectron microscopic studies performed in Leydig cells and in stably transfected L cells have allowed to study intracellular traffic of the LH receptor. The same approach was used to study the transendothelial transfer of hCG in testicular microvasculature.

The spatio-temporal dynamics of the solar magnetic field has been investigated by using NSO/Kitt Peak magnetic synoptic maps covering the period 1976 August-2003 September. The field radial component, for each heliographic latitude, has been decomposed in intrinsic mode functions through the Empirical Mode Decomposition in order to investigate the time evolution of the various characteristic oscillating modes at different latitudes. The same technique has also been applied on synoptic maps of the meridional and east-west components, which were derived from the observed line-of-sight projection of the field by using the differential rotation. Results obtained for the ~22 yr cycle, related to the polarity inversions of the large-scale dipolar field, show an antisymmetric behavior with respect to the equator in all the field components and a marked poleward flux migration in the radial and meridional components (from about –35° and +35° in the southern and northern hemispheres, respectively). The quasi-biennial oscillations (QBOs) are also identified as a fundamental timescale of variability of the magnetic field and associated with poleward magnetic flux migration from low latitudes around the maximum and descending phase of the solar cycle. Moreover, signs of an equatorward drift, at a ~2 yr rate, seem to appear in the radial and toroidal components. Hence, the QBO patterns suggest a link to a dynamo action. Finally, the high-frequency component of the magnetic field, at timescales less than 1 yr, provides the most energetic contribution and it is associated with the outbreaks of the bipolar regions on the solar surface.

Hormonal receptors are rare and fragile molecules. Their study was difficult and often yielded contradictory results until immunological and molecular probes became available. Sex steroid receptor cDNAs were cloned in 1986–1987. Monoclonal antibodies had previously been prepared and for this reason the understanding of their structure and function is already very advanced to date. In contrast, gonadotropin receptors were not cloned until 1989–1990 and well-characterized antibodies still remain a problem in many cases and thus our knowledge of their mere basic structural and functional features is still preliminary in many cases.

Monoclonal antibodies have been raised against porcine LH receptor and allowed to clone the corresponding messenger RNA from testicular cells. The structure of the LH receptor have been determined. It shows similarities but also differences to other G protein coupled receptors. In particular a large extracellular domain is specific for that family of receptors. Variants forms of the LH receptor generated by alternative splicing and lacking transmembrane domains have been isolated. Immunochemical and immunocytochemical studies have been performed. Three different forms of the LH receptor are physiologically expressed: a mature 85 kDa transmembrane species, a 68 kDa high mannose containing species corresponding to a precursor which accumulate inside the cells, and truncated 45-48 kDa molecular weight species corresponding to the variant messenger RNAs identified during the cloning of the receptor. A novel zonation of the ovary has been described by immunocytochemical studies. Cross hybridisation with the LH receptor clone allowed to isolate the related human TSH receptor from thyroïds. The human LH and FSH receptor genes have been localized to chromosome 2p21 and the TSH receptor gene to chromosome 14q31. The genes are very large and have introns only within their 5' part corresponding to the extracellular domain of the receptor.

Monoclonal antibodies have been raised against porcine LH receptor and allowed to clone the corresponding messenger RNA from testicular cells. Cross hybridisation with the LH receptor clone allowed to isolate a clone corresponding to the human TSH receptor from thyroids. The structure of both receptors have been determined. They show similarities but also differences to other G protein coupled receptors. In particular a large extracellular domain is specific of that new family of receptors. Variant forms of the LH receptor lacking transmembrane domains have been isolated. The obtention of monoclonal antibodies against both receptors allowed immunochemical and immunocytochemical studies to be performed. The human LH receptor gene have been localized to chromosome 2p21 and TSH receptor gene to chromosome 14q31. The complete organisation of the human TSH receptor gene has been determined.

Proacrosin biosynthesis timing during human spermatogenesis has been studied using the monoclonal antibody 41)4 (mAb 4D4). Frozen and paraffin-embedded sections of testicular biopsies were labelled by standard indirect immunofluorescence and avidin-biotin immunoperoxidase procedures. The labelling specificity was checked by immunochemistry assays on unrelated tissues and by western blotting of testis extracts showing that only the 50–55×103 Mr proacrosin was recognized by mAb 4D4. Proacrosin was first observed in the Golgi region of midpachytene primary spermatocytes. In late pachytene primary spermatocytes, proacrosin was observed in two regions located at opposite nuclear poles. During the subsequent steps of the first meiotic division, the two bodies containing proacrosin were located: (i) on opposite sides of the equatorial plate during metaphase; along the microtubular spindle during anaphase; and close to each chromosomal aggregate during telophase. Two bodies containing proacrosin were still observed in interphasic secondary spermatocytes. The single labelled area observed in early spermatids was found to increase considerably in size during spermiogenesis. Anomalies of proacrosin scattering were observed in patients with Golgi complex partitioning failure. These data’ reveal proacrosin biosynthesis during diploid and haploid phases of human spermatogenesis and the proacrosin partitioning pattern during meiosis.

A method for the purification of epithelial cells from the three anatomical regions of the rat epididymis (corpus, caput and cauda) is described. An enzymic digestion followed by sedimentation of crude cell suspension on discontinuous Percoll gradient yielded quite pure active epithelial cell population as judged by morphological and functional studies. Electron microscopy analysis showed that cells from bands corresponding to densities 1.055 and 1.06 g/ml the gradient preserved a morphology compatible with their epithelial origin and their absorptive and secretory functions. Moreover, they stained positively with anticytokeratin antibody (95-97%) and were negative for antidesmin antibody. They selectively bound L-carnitine through a time-dependent and saturable system and differences in the rate of binding were apparent according to the three anatomical regions of the epididymis.

We have observed typical cytomegalovirus cytopathology associated with multifocal inflammatory and necrotic lesions of peripheral nerve in biopsy specimens from 4 patients who developed a rapidly progressive, multifocal neuropathy late in the course of human immunodeficiency virus infection. The inflammatory infiltrates, which contained numerous polymorphonuclear cells, were associated with mixed, axonal, and demyelinative lesions of nerve fibers. One of these patients improved on treatment with DHPG (9-[2-hydroxy-l(hydroxymethyl) ethoxymethyl] guanine) and remains stable after 18 months. The other 3 died soon after the onset of the neuropathy. In another patient with acquired immunodeficiency syndrome, who developed a severe, predominantly motor neuropathy of the lower limbs, the nerve biopsy did not reveal cytomegalovirus inclusions, but the neurological deficit improved on treatment with DHPG. The patient died from cachexia 2 months later; numerous cytomegalovirus lesions were found in the spinal cord at the time of postmortem examination. The multifocal necrotic endoneurial nerve lesions with polymorphonuclear cell infiltration we describe may help identify cytomegalovirus neuropathy when characteristic inclusions are not present in the biopsy specimen.

Context.—No pharmacological therapeutic protocol has been found effective in modifying the clinical course of acute respiratory distress syndrome (ARDS) and mortality remains greater than 50%.Objective.—To determine the effects of prolonged methylprednisolone therapy on lung function and mortality in patients with unresolving ARDS.Design.—Randomized, double-blind, placebo-controlled trial.Setting.—Medical intensive care units of 4 medical centers.Participants.—Twenty-four patients with severe ARDS who had failed to improve lung injury score (LIS) by the seventh day of respiratory failure.Interventions.—Sixteen patients received methylprednisolone and 8 received placebo. Methylprednisolone dose was initially 2 mg/kg per day and the duration of treatment was 32 days. Four patients whose LIS failed to improve by at least 1 point after 10 days of treatment were blindly crossed over to the alternative treatment.Main Outcome Measures.—Primary outcome measures were improvement in lung function and mortality. Secondary outcome measures were improvement in multiple organ dysfunction syndrome (MODS) and development of nosocomial infections.Results.—Physiological characteristics at the onset of ARDS were similar in both groups. At study entry (day 9 [SD, 3] of ARDS), the 2 groups had similar LIS, ratios of PaO2 to fraction of inspired oxygen (FIO2), and MODS scores. Changes observed by study day 10 for methylprednisolone vs placebo were as follows: reduced LIS (mean [SEM], 1.7 [0.1] vs 3.0 [0.2]; P

Using 99Tcm-diethylenetriaminepentaacetate (DTPA) an acceptable estimate of glomerular filtration rate (GFR) can be obtained in adult patients by the equation GF (ml/min) = (0.14 x W + 5) x 1000 x k, where W is the 'ideal' body mass (kg) and k the slope determined by two plasma samples. This has been verified in comparison with the results of the Russell (two samples) and Christensen (one sample) methods in 50 patients. The procedure, which does not require determination of the injected dose, could be useful in patients undergoing sequential renal scintigraphy with 99Tcm-DTPA, for example, to check a doubtful value of glomerular filtration obtained by external counting.

Purpose: A morphological and morphometric study of the adult zebrafish ocular surface was performed to provide a comprehensive description of its parts and to evaluate its similarity to the human. Materials and Methods: The eyes of adult zebrafish were processed for light, transmission and scanning electron microscopy, and for immunohistochemical stain of corneal nerves; a morphometric analysis was also performed on several morphological parameters. Results: The corneal epithelium was formed by five layers of cells. No Bowman’s layer could be demonstrated. The stroma consisted of lamellae of different thickness with few keratocytes. The Descemet’s membrane was absent as the flat and polygonal endothelial cells directly adhered to the deepest corneal lamella. The immunohistochemical stain of neurofilaments failed to demonstrate corneal nerve fibers. The conjunctival epithelium was stratified, overlying the stroma formed by a subepithelial and a deep layer, this latter connected to the scleral cartilage. In the peripheral cornea and in the conjunctiva, many goblet and rodlet cells were observed. The morphometric analysis showed that the peripheral cornea epithelium was thicker when compared to the other parts of the ocular surface, with smaller superficial cells. Desmosomes and hemidesmosomes in the conjunctiva were significantly fewer in number than the other parts of the ocular surface. The stroma was thinner in the conjunctiva than in the cornea, while corneal lamellae were thicker in the intermediate stroma. Conclusions: The zebrafish ocular surface showed significant differences compared to the human, such as the absence of Bowman’s layer, Descemet’s membrane and corneal nerve fibers, the reduced stromal thickness, and the presence of rodlet cells. On the basis of these original findings, it is suggested that the use of the zebrafish as a model for studying normal or pathological human corneas should be undertaken with particular caution.

BACKGROUND: The pituitary tumour transforming gene (pttg) plays a central role in pituitary tumorigenesis, but PTTG protein expression is poorly documented and its relationship with tumour cell proliferation and the prognosis of pituitary adenomas is unclear. AIM: The aim of this study was to evaluate the immunohistochemical expression of PTTG and Ki-67 in 45 human pituitary adenomas according to the tumour histotype, aggressiveness and persistence/recurrence status. PATIENTS AND METHODS: The tumours comprised 37 macroadenomas and 8 microadenomas. Twenty patients experienced disease persistence or recurrence after transsphenoidal surgery. Disease recurrence was observed in 16 patients, 8-72 months after surgery. RESULTS: No PTTG or Ki-67 expression was detected in normal pituitary tissue. In pituitary adenomas, tumour nuclei were positive for PTTG and Ki-67 in 89 and 98% of samples, respectively, and there was a strong correlation between the expression of the two proteins (P < 0.001). By the ROC curves method, a PTTG score of 3.3% was the best cut-off for distinguishing between recurrent and nonrecurrent pituitary adenomas (P < 0.05; sensitivity 60%; specificity 76%). A 2.9% cut-off was obtained for both PTTG (P < 0.01; sensitivity 77%; specificity 71%) and Ki-67 (P < 0.05; sensitivity 85%; specificity 64%) among patients with more than 1 year of follow-up. Neither PTTG nor Ki-67 expression was influenced by the maximal tumour diameter, tumour grade, age, gender or presurgical medical treatment. Both PTTG and Ki-67 tumour score > 2.9% identified a subgroup of patients with a significantly higher recurrence-free interval (P < 0.01). By multivariate analysis, a > 2.9% Ki-67 tumour score was the best predictor of pituitary tumour persistence/recurrence after surgery (chi(2) = 8.2, P < 0.01). CONCLUSION: PTTG is expressed in approximately 90% of pituitary tumours of different histotypes but with a high variability from one case to another. As expected, PTTG expression parallels that of Ki-67 and both are correlated to a more aggressive behaviour. However, a 2.9% Ki-67 cut-off proved to be the most reliable biological marker for predicting the recurrence potential of these tumours, when an adequate postsurgical follow-up is considered.