Disproportionate increases of white matter in right frontal lobe in Tourette syndrome

OBJECTIVE

Based on previous findings implicating abnormalities of cortico-striatal-thalamo-cortical circuitry in Tourette syndrome (TS), the authors performed a volumetric analysis of frontal and nonfrontal tissue (gray + white matter) in boys with TS, with and without attention deficit hyperactivity disorder (ADHD).

METHODS

Frontal and nonfrontal gray and white matter compartment volumes, obtained by a MRI protocol, were analyzed with a 2 x 2 factorial multivariate analysis of variance approach for associations with a TS or ADHD factor in 11 boys with TS only, 14 with TS + ADHD, 12 with ADHD only, and 26 healthy boys.

RESULTS

In subjects with TS, the right frontal lobe showed a larger proportion of white matter. In addition, results were consistent with previous reports of reduced frontal lobe volumes associated with ADHD. Our analyses suggested these reductions to be mainly the consequence of smaller gray matter volumes, particularly on the left.

CONCLUSIONS

These findings, suggesting the volumetric composition of frontal lobe tissue to be different in TS, support the hypothesis proposing frontostriatal pathway involvement in the pathophysiology of the disorder. Differences in composition of right frontal lobe attributable to white matter do not definitively implicate the hypothesized fiber pathways; however, considered in the context of the unilateral directionality of frontal-striatal circuitry, these results suggest the white matter connections as one explanation for basal ganglia anomalies (loss of normal left > right asymmetry) in TS.

Fabrication of microgratings on the ends of standard optical fibers by the electrostatic self-assembly monolayer process

The electrostatic self-assembly monolayer process has been utilized for what is believed to be the first time to deposit quarter-wavelength stacks on the end faces of cleaved and polished optical fibers. Standard multimode optical fibers as well as single-mode optical fibers were used as substrates with different coating materials to fabricate broadband filters, and the experimentally measured spectral responses of these devices are shown. These optical filter structures were employed to develop chemical sensors that use an unperturbed reference wavelength to normalize the output signal.

Incidence and surgical repair rates of hypospadias in New York state

OBJECTIVES

To determine the trend of hypospadias incidence in New York State (NYS) by retrospectively evaluating both the incidence and surgical repair rates of hypospadias. Epidemiologic studies in the United States and Europe have suggested an observable trend in the incidence of hypospadias during the past 30 years. A comparison of the results from these studies, however, revealed inconsistent trends.

METHODS

The incidence and surgical repair rates of hypospadias between 1983 and 1995 were extracted from the Congenital Malformations Registry and State Wide Planning Research Cooperative System of NYS. Pearson's correlation coefficient was used to determine the direction and magnitude of change.

RESULTS

Neither the incidence nor the repair rates of hypospadias in NYS between 1983 and 1995 changed significantly during the course of these 12 years (r = -0.225, P = 0.45 and r = -0.010, P = 0.92, respectively).

CONCLUSIONS

The results demonstrated no statistically observable trend in either the incidence or surgical repair rates of hypospadias in NYS between 1983 and 1995.

An analysis of two refolding routes for a C-terminally truncated human collagenase-3 expressed in Escherichia coli

We describe here the expression of a C-terminally truncated form of human procollagenase-3 in Escherichia coli. The protein was found almost exclusively in inclusion bodies that were solubilized and refolded by two separate methods and then purified on Ni-NTA agarose. The purified proenzyme could be activated with either trypsin or APMA and active enzyme could be purified on a peptidic hydroxamate affinity column. Competitive elution from the affinity matrix yielded a highly purified preparation.

Alpha-adrenoceptor antagonists in the treatment of benign prostatic hyperplasia

Lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH) have a significant impact on the lifestyle of older men. Transurethral resection of the prostate (TURP) is the most effective surgical therapy for this condition but an increasing number of patients are electing conservative medical therapy. Alpha-Adrenoceptor antagonists and 5alpha-reductase inhibitors are the 2 categories of drug therapy currently available for BPH. Use of alpha-adrenoceptor antagonists in the treatment of BPH is based on their ability to prevent the neural stimulation which induces prostate smooth muscle contraction, producing lower urinary tract symptoms. Several studies have demonstrated that alpha-receptors predominate in the prostatic stroma, capsule and bladder neck. Initial work focused on the use of phenoxybenzamine, a nonspecific alpha-blocker, in the treatment of BPH. While results were promising, significant adverse effects and concern over potential mutagenicity have resulted in a lack of use of this medication for this indication. Subsequent attention was directed towards the short-acting alpha-specific antagonist prazosin. Results conflicted regarding whether an actual sustained improvement in lower urinary tract symptoms could be achieved with this medication, and because of twice daily dosing compliance issues were a drawback. Thus, the mainstay in pharmacological treatment of BPH over the past decade has been 2 once-a-day alpha-specific antagonists, doxazosin and terazosin. Over 75% of all prescriptions written for BPH are for one of these 2 medications. Despite their tremendous success in both decreasing urinary symptoms and increasing urinary flow rates, systemic adverse effects can be bothersome. Recently, efforts have focused on use of alpha1A-urospecific antagonists such as tamsulosin and alfuzosin in an attempt to achieve similar clinical results as doxazosin and terazosin without systemic adverse effects. Thus far, results are promising, but long term studies must be done to determine whether pharmacological uroselectivity is actually clinically relevant.

Screen-film versus computed radiography imaging of the hand: a direct comparison

OBJECTIVE

Computed radiography of the musculoskeletal system has the potential to become a powerful tool in the practice of diagnostic radiology. It addresses many of the geographic and film-distribution concerns facing diagnostic imaging. We undertook this study to compare and document the quality of computed radiographs and conventional screen-film images before widespread implementation.

MATERIALS AND METHODS

We evaluated clinical images using direct comparison. Bilateral hand images from 50 patients were scored independently by six musculoskeletal radiologists. In each case one hand was imaged with a conventional screen-film technique and the other with computed radiography. Images were masked to eliminate as much bias as possible. The numeric scores assigned to the images by the observers were analyzed using Student's t test.

RESULTS

Computed radiographs were judged with statistical significance to be better than conventional screen-film images in all features judged by the observers, including bone cortex, bone trabeculae, corticomedullary junction, distal phalangeal tuft, soft tissues, fat planes, bone-soft-tissue interface, and overall contrast and density.

CONCLUSION

The statistically significant determination that the image quality of computed radiographs is at least as good as screen-film images allows confident use of computed radiography and enables radiologists to take advantage of its many other practical capabilities related to image distribution, storage, cost, and geographic coverage without sacrificing image quality.

An investigation of the temporal induction of cytokine mRNAs in LPS-challenged thioglycollate-elicited murine peritoneal macrophages using the reverse transcription polymerase chain reaction

OBJECTIVE AND DESIGN

A comprehensive study to standardise interleukin (IL)-1 alpha, -1 beta, -6, -10, -12 and tumour necrosis factor alpha (TNF alpha) mRNA detection in murine peritoneal macrophages, using the reverse transcription polymerase chain reaction (RT-PCR) was carried out.

SUBJECTS

Thioglycollate-elicited peritoneal exudate cells were harvested from female BALB/c mice and the adherent macrophage fraction isolated for use.

TREATMENT

Peritoneal macrophages (1 x 10(6)) were incubated in the presence or absence of lipopolysaccharide (LPS; at a final concentration of 1 microgram/ml) for 0, 1, 2, 3, 4, 5 and 24 h.

METHODS

Culture supernatants and cells were harvested at each time point, the secreted cytokine protein levels quantified by sandwich immunoassays and the cytokine mRNA levels assessed by RT-PCR.

RESULTS

The IL-6 mRNA was not expressed in detectable amounts in the macrophages, unless challenged with LPS. TNF alpha, IL-1 alpha, IL-1 beta, IL-10 and IL-12 mRNAs were expressed in both stimulated and unstimulated macrophages. The levels of the PCR products and thus mRNAs of all the cytokines increased with LPS stimulation, maximal levels being achieved 3 to 5 h post stimulation.

CONCLUSIONS

RT-PCR produced consistent results, indicating that this technique could be used to investigate the effect of biological mediators and novel pharmacological agents on cytokine mRNA levels in macrophages.

Predictive factors for response to medical therapy in bacterial ulcerative keratitis

BACKGROUND

Fifty-four consecutive cases of culture-positive bacterial ulcerative keratitis presenting at a major university hospital were reviewed to identify factors predictive of response to medical therapy for bacterial ulcerative keratitis (BUK).

METHODS

Eleven patients (20%) failed medical therapy (defined as the need for surgical intervention or cyanoacrylate gluing). Using multivariate logistic regression, the following variables were evaluated: (1) predisposing ocular factors (e.g., contact lens wear), (2) pre-existing ocular diseases, (3) ulcer size, and (4) the number of topical ocular medications used at the time of presentation.

RESULTS

We noted certain factors to be potentially predictive of medical therapy outcome. The average size of the ulcer at the time of presentation was 4.4 +/- 2.4 mm in the failure group but only 2.5 +/- 1.9 mm for the success group (P = 0.027). In addition, patients in the medical failure group used more topical ocular medications at the time of presentation (P = 0.0075). Further analysis of the individual topical ocular medications revealed that the use of corticosteroids was higher in the failure group (56% vs 12%, P = 0.0005 by Fisher's exact test). Other factors such as patient age, the type of organism(s), and the time elapsed between the onset of symptoms and the beginning of definitive therapy were not statistically significant.

CONCLUSION

In this population, ulcer size at the onset of antibacterial treatment and the use of certain ocular medications, specifically corticosteroids, were significant predictive factors for failure of medical therapy for BUK.

Effect of pharmacological agents on the productions of interleukin-10 by the murine D10.G4.1 TH2 cell line in vitro

It is becoming increasingly clear that the clinical courses of a variety of autoimmune and infectious diseases are influenced by the balance of TH1 and TH2 cell subsets that are generated during the immune response. IL-10 is one of several cytokines which influences the differentiation of TH cell subsets and represents a target for therapeutic intervention. We have evaluated a variety of pharmacological agents for their ability to modulate IL-10 release by the murine D10.G4.1 TH2 cell line when stimulated with concanacavalin-A in the presence of IL-1 alpha. Several were inhibitory, and the concentrations which caused a 50% reduction in IL-10 production were 0.38 microM cyclosporin-A, 0.0073 microM dexamethasone, 0.045 microM prednisolone and 0.31 microM cycloheximide. Methotrexate and pentoxifyline caused a weak but statistically significant reduction in IL-10 production at a concentration of 10 microM (P < or = 0.05), whereas amrinone and azathioprine had no clear effect. The pharmacological agents tested are known to exert multiple effects and were evaluated with a view to their use as reference standards in an ongoing screening programme to identify novel compounds which specifically modulate Il-10 production.

BTS 71 412: in vitro profile of a novel pyrazolinone immunosuppressant

The effect of BTS 71 412, 4-acetyl-1-(4-chlorophenyl)-3-(2-methylthiophenyl)- 3-pyrazolin-5-one, has been determined on a variety of immune reactions in vitro in order to gain a further insight into the mechanisms whereby this novel immunosuppressive drug suppresses cell and antibody mediated immune responses in vivo. BTS 71 412 markedly inhibited [3H]thymidine incorporation by mouse splenocytes activated with concanavalin-A (IC50 = 20.1 microM), phytohaemagglutinin (IC50 = 4.6 microM), lipopolysaccharide (LPS) (IC50 = 3.2 microM), anti-IgM (mu-chain specific) (IC50 = 2.6 microM), or mixed lymphocyte culture (IC50 = 8.4 microM). Activity of BTS 71 412 was not associated with a reduction in cell viability. BTS 71 412 also prevented [3H]thymidine incorporation by the murine HT-2 helper T-cell clone when cultured with IL-2 (IC50 = 7.6 microM) or IL-4 (IC50 = 7.3 microM), enriched Thy-1+ T-lymphocytes stimulated with phorbol 12-myristate 13-acetate plus ionomycin (IC50 = 3.6 microM), and enriched B220- B-lymphocytes stimulated with LPS (IC50 = 3.0 microM). Splenocytes cultured with BTS 71 412 produced lower levels of interleukin (IL)-2, IL-10 and interferon-gamma when stimulated with concanavalin-A (IC50 values 42 microM, 22 microM and 60 microM, respectively). The compound suppressed in vitro antibody responses to keyhole limpet haemocyanin (IC50 = 2.3 microM), but did not reproducibly inhibit IL-6 or tumour necrosis factor alpha production by adherent peritoneal macrophages stimulated with LPS in vitro. These data indicate that BTS 71 412 specifically inhibits both B- and T-lymphocyte activation and proliferation but does not affect macrophage activation in vitro.

A gyroscope deviometer for measurement of strabismus

We describe a hand-held gyroscope deviometer that an examiner can use to measure strabismic deviations without prisms. The deviometer is ideally suited for use with small children who will not allow prisms to be held near their eyes, and adults with poor fixation in one eye. The device consists of a fixation light attached to a gimbal-mounted single-axis gyroscope. The gyroscope provides the necessary reference for horizontal deviations. Gravity provides the reference for vertical deviations. As the patient observes his or her reflection with the fixing eye in a plane mirror at the end of the room, the examiner positions the corneal light reflex in the pupil of the deviating eye and presses a rocker switch to the "reset" position, zeroing the deviometer. The examiner then aims the deviometer fixation light at a reflection of itself in a plane mirror located on the wall behind the subject and presses the rocker switch to the "read" position. Horizontal and vertical deviations are displayed to the nearest degree. The accuracy of the device is dependent upon the examiner's ability to position the corneal light reflex correctly in the pupil of the deviating eye.

Insufficiency stress fractures

Bones weakened by osteopenia have insufficient elastic resistance to withstand even the minimal mechanical stresses of normal daily activity. Repetitive subthreshold injury to these susceptible bones results in insufficiency-type stress fractures. The spine, pelvis, and lower extremities are commonly affected by these fractures. Insufficiency fractures create a diagnostic challenge for clinicians and radiologists alike. The radiographic evidence of the fracture is often so subtle that it escapes detection. Conversely, findings on other studies may be so striking that they suggest metastatic disease. Insufficiency fractures are often subjected to unnecessary biopsies, and they have been treated unwittingly with chemotherapy and radiation therapy. Radiologists are in a key position to prevent these errors. A thorough familiarity with the characteristic appearance and location of these fractures assures the correct diagnosis.

Radiology of metabolic bone disease

A variety of radiographic findings are encountered in metabolic bone disease. These findings, though often subtle, are often diagnostic. Hyperparathyroidism, osteomalacia, renal osteodystrophy, Paget's disease, and other forms of metabolic bone disease produce characteristic radiographic manifestations. Computed tomography and magnetic resonance imaging make contributions in selected circumstances, but plain film radiography remains the primary imaging tool.

Insufficiency fractures of the pelvis that simulate metastatic disease

Insufficiency fractures of the pelvis, which almost always occur in elderly women with osteoporosis, are often misinterpreted as metastatic disease. The initial symptom of such fractures is severe pain unassociated with an obvious history of trauma. The typical sites of involvement are the sacrum, the iliac bones, and the pubis. The plain film appearance of the sacral and iliac fractures is usually subtle and easily overlooked, and bone scans will show the abnormal areas more readily. The existence of multiple fractures not only in the pelvis but also in the vertebrae and ribs should suggest the diagnosis of insufficiency-type stress fractures. Computed tomography can exclude the presence of a destructive process and an associated soft tissue mass, as would be seen in metastatic disease. If insufficiency fractures are identified in the typical anatomic locations, bone biopsy is unnecessary.

Insufficiency fractures of the sternum: a consequence of thoracic kyphosis?

Osteoporosis often leads to thoracic compression fractures and progressive thoracic kyphosis. The kyphosis creates a deforming stress on the sternum that may eventuate in an insufficiency-type stress fracture. The findings in four women with osteoporosis, thoracic kyphosis, and insufficiency fractures of the sternum are reported.

Supraacetabular insufficiency fractures

Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women.

Insufficiency fractures of the sacrum

Insufficiency stress fractures may occur in the sacrum after radiation therapy or secondary to postmenopausal or steroid-induced osteoporosis. These fractures are often either overlooked or confused both clinically and radiographically with metastatic disease. Findings on plain films and conventional tomograms are often subtle. Radionuclide bone scans show a characteristic distribution of increased uptake. Computed tomography is the definitive technique for demonstrating the fractures.

Giant cell tumor: ossification in soft-tissue implants

Benign giant cell tumor of bone may be implanted into the surrounding soft tissues at the time of surgery or pathologic fracture. These soft-tissue implants may produce ossification that is radiographically visible. A review of the available radiographs of 400 cases of giant cell tumor from the Mayo Clinic and 700 cases seen in consultation yielded 17 examples of this phenomenon. In all but one case, the ossification was found at the periphery of the implant. The radiographic appearance of these implants is characteristic. Recognition of this appearance is necessary so that the tumor may be totally eradicated.