A preliminary investigation of Beta-hCG expression in patients with osteosarcoma.

There are eight reported cases in the literature of osteosarcomas secreting ß-hCG. Our primary aim was to investigate the rate of ß-hCG expression in osteosarcoma and attempt to understand the characteristics of osteosarcomas that secrete ß-hCG. We reviewed 37 histopathology slides (14 biopsies and 23 surgical specimens) from 32 patients with osteosarcoma. The slides were retrospectively stained for ß-hCG expression. Patient and tumour characteristics, including age, gender, tumour location, subtype, proportion of necrosis, presence of metastases and recurrence were recorded. A total of five of the 32 tumours were found to be positive for ß-hCG expression (one strongly and four weakly). This incidence of this expression was found in tumours with poor histological response to neoadjuvant chemotherapy. The use of ß-hCG expression as a diagnostic, prognostic or follow-up marker is questionable and needs further investigation with a larger sample size.

Lumbar disc herniation in young children.

AIM: This article explores lumbar disc herniation in young children through focusing on matters relevant to patient presentation, physical examination, differential diagnosis, imaging and treatment. METHODS: Major databases were searched for studies that addressed lumbar disc herniation in young children. RESULTS: Diagnosis of lumbar disc herniation in young children is usually delayed because of the rarity and lack of experience with this entity and the difficulty in extracting a reliable medical history. Nevertheless, lumbar disc herniation should be considered in the differential diagnosis of any young child presenting with a chief complaint of back pain and/or radiculopathy, especially in the setting of recent trauma. This should be coupled with a directed physical examination to elicit signs and narrow the differential diagnosis. Imaging studies, mainly magnetic resonance imaging, will help establish a diagnosis; yet radiographs are still required to exclude other spinal lesions. The initial management of lumbar disc herniation in children is the same as that in adults and consists of conservative treatment unless lumbar disc herniation affects the patient's motor and neurological functions in which case, early surgical treatment must be undertaken. Although the latter remains more difficult, current experience suggests a favourable outcome. CONCLUSION: Awareness of lumbar disc herniation will help the paediatrician extract a relevant medical history, perform a directed physical examination, and order appropriate imaging studies. This will aid in initiating early intervention, be it conservative or operative, and achieving a favourable outcome.

Single-scan extraction of two-dimensional parameters of infrared focal plane arrays utilizing a Fourier-transform spectrometer.

We present what is believed to be a novel experimental method to measure the technological parameters (spectral response and quantum yield) of an infrared focal plane array. This method makes original use of a Fourier transform spectrometer, which allows us to simultaneously extract the spectral performances of all pixels from one single set of measurements. The methodology used and the principle of the experimental setup are detailed. A Fourier analysis is shown to provide various optogeometrical information on the detector microstructure. A demonstrator based on the HgCdTe technology was designed, and satisfactory experimental results were obtained.

In situ optical testing of infrared lenses for high-performance cameras.

We propose to evaluate infrared lenses with a dedicated analyzer having the same mechanical interface as the usual cameras. The proposed analysis is based on a wavefront measurement and allows a diagnostic of possible internal defects of the analyzed lens. The infrared lens analyzer described is constituted with a quadriwave lateral shearing interferometer and works with a blackbody light. We describe the response of this interferometer and an innovative method to obtain the wavefront under test. We finally present the experimental analysis of long-wavelength infrared lenses and the particular case of a modified lens that generates a large spherical aberration.

Random quasi-phase-matching in bulk polycrystalline isotropic nonlinear materials.

Three-wave mixing in nonlinear materials--the interaction of two light waves to produce a third--is a convenient way of generating new optical frequencies from common laser sources. However, the resulting optical conversion yield is generally poor, because the relative phases of the three interacting waves change continuously as they propagate through the material. This phenomenon, known as phase mismatch, is a consequence of optical dispersion (wave velocity is frequency dependent), and is responsible for the poor optical conversion potential of isotropic nonlinear materials. Here we show that exploiting the random motion of the relative phases in highly transparent polycrystalline materials can be an effective strategy for achieving efficient phase matching in isotropic materials. Distinctive features of this 'random quasi-phase-matching' approach are a linear dependence of the conversion yield with sample thickness (predicted in ref. 3), the absence of the need for either preferential materials orientation or specific polarization selection rules, and the existence of a wavelength-dependent resonant size for the polycrystalline grains.

Pseudomonas pericarditis in an immunocompetent newborn: unusual presentation with review of the literature.

Acute purulent pericarditis is a rare entity in the neonatal age group. The most common isolated organisms are Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae. Other organisms, like Pseudomonas aeruginosa, have been seldom implicated with only one case of Pseudomonas pericarditis reported in the neonatal period. The prognosis is often considered very poor in this age group. This article describes Pseudomonas pericarditis in a 1-week-old immunocompetent female newborn who was successfully managed with combined medical and surgical therapy.

Radial forearm fasciocutaneous free-tissue transfer in ankle and foot reconstruction: review of 17 cases.

Seventeen patients who underwent soft-tissue reconstruction of various anatomic regions of the foot and ankle, using the radial forearm fasciocutaneous free flap, are reported. The procedures were performed between January, 1992 and December, 1998. Indications for reconstruction included diabetes and/or vascular insufficiency (four patients), soft-tissue defects (six patients), and chronic osteomyelitis (seven patients). The weight-bearing surface of the foot was involved in 16 patients. Defects ranged in size from 35 to 206 cm2 (mean: 86.2 cm2). At a mean follow-up of 3.8 years, the radial forearm flap was successful in all cases (100 percent). Flap complications included superficial infection (three patients), and minor wound dehiscence at the flap-leg-skin interface (two patients). Recurrent ulceration occurred in two patients; both were diabetics with weight-bearing flaps. Donor-site complications included partial skin graft loss with tendon exposure in one patient, which healed with conservative management. Recurrent or persistent osteomyelitis was not demonstrated in any of the patients. Of the 16 patients with weight-bearing flaps, 12 were ambulatory, three had limited ambulation, and one was non-ambulatory. Three patients required modified shoes. No debulking of the transferred flaps was necessary. The radial forearm flap is one of the preferred flaps for reconstruction of moderate-sized ankle and foot defects, for weight-bearing surfaces, and in the treatment of osteomyelitic and diabetic wounds. It meets most of the anatomic prerequisites for an ideal foot coverage; it also facilitates the restoration of normal foot contour, allowing patients to wear ordinary shoes. The flap provides a durable and stable weight-bearing plantar surface during ambulation, and achieves excellent aesthetic results; when used as a neurosensory flap, it permits adequate reinnervation.

Aspergillus vertebral osteomyelitis in a child with a primary monocyte killing defect: response to GM-CSF therapy.

We report the first case of vertebral aspergillosis in a child with a primary defect in monocyte killing, an extremely rare immunodeficiency The diagnosis of defective monocyte killing was made by an in vitro assay that showed normal killing of Staphylococcus aureus by the patient's neutrophils but impaired killing by his monocytes. Importantly, the extensive granulomatous infection that involved the vertebral column, posterior mediastinum, pleura, and lung was not responsive to aggressive treatment with a combination of liposomal amphotericin B. intralesional amphotericin B. itraconazole, and granulocyte transfusions. Dramatic clinical and radiological improvement was only seen after the addition of granulocyte macrophage-colony stimulating factor (GM-CSF) to his treatment regimen. The use of GM-CSF in the treatment of invasive aspergillosis in immunocompromised patients requires further evaluation.

Slow-onset, long-duration 3-(3',4'-dichlorophenyl)-1-indanamine monoamine reuptake blockers as potential medications to treat cocaine abuse.

A series of 3-(3',4'-dichlorophenyl)-1-indanamine monoamine reuptake blockers have been synthesized in an effort to develop a compound that could be used as a maintenance therapy to treat cocaine abuse. Since the effects of cocaine on dopamine (DA) and serotonin (5HT) transporters are important components of its pharmacological activity, the focus was on nonselective inhibitors of monoamine transport. To reduce or eliminate the abuse potential of a DA reuptake blocker, the compounds were designed to be slow-onset, long-duration prodrugs whose N-demethylated metabolites would have increased activity over the parent compound with the ideal being a parent compound that has little or no activity. To achieve this, pairs of compounds with different groups on the amine nitrogen and with and without an additional N-methyl group were synthesized. All of the synthesized compounds were screened for binding and reuptake at the cloned human DA, 5HT, and norepinephrine (NE) transporters. As previously found, trans isomers are nonselective blockers of DA, 5HT, and NE reuptake, cis isomers with small N-alkyl groups are selective blockers of 5HT reuptake, and tertiary amines of the trans compounds are less potent than the corresponding N-demethylated secondary amines as blockers of DA reuptake. Larger N-alkyl groups in both the trans and cis series were found to reduce activity for the 5HT and NE transporters with less effect at DA transporters. Selected trans compounds were also screened for locomotor activity in mice and generalization to a cocaine-like profile in rats. With intraperitoneal administration, all of the trans isomers showed a slow onset of at least 20 min and an extremely long duration of action in the locomotor assays. Several of the trans compounds also fully generalized to a cocaine-like pharmacological profile. An initial lead compound, the N,N-dimethyl analogue trans-1b, was resolved into chirally pure enantiomers. Surprisingly, both enantiomers were found to have significant affinity for the DA transporter and to cause locomotor activation. This is in contrast to the N-methyl compound in which only the (+)-enantiomer had significant activity. The absolute configuration of the more active enantiomer was determined by X-ray crystallography to be 3R,1S.

Simultaneous open reduction and Salter innominate osteotomy for developmental dysplasia of the hip.

We have studied retrospectively 37 hips in 36 children at an average of 91 months after simultaneous open reduction and Salter innominate osteotomy for developmental hip dysplasia. At the latest review 97.3% were clinically and 83.8% radiologically good or excellent. In three hips (8%) there were signs of avascular necrosis, but only one had been symptomatic. There were no cases of recurrent posterior displacement.