Syringomyelia in mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome): imaging findings following bone marrow transplantation

We present the imaging findings in a patient with mucopolysaccharidosis (MPS) type VI (Maroteaux-Lamy syndrome) who developed holocord syringomyelia. This represents the only reported case of syrinx formation in a child with MPS VI. Clinical, neurologic and spinal magnetic resonance imaging findings are presented. The patient has maintained a stable clinical and neurologic course over the period following allogeneic bone marrow transplant.     

Transition probability cell cycle model. Part I--Balanced growth

In this study, we have identified and characterized functional alpha2-adrenergic receptor (alpha2-AR) subtypes in human corpus cavernosum and in cultured human corpus cavernosum smooth muscle cells. Analysis of total RNA, isolated from whole corpus cavernosum tissue and smooth muscle cells, by RNase protection assays, demonstrated expression of mRNA for alpha2A, alpha2B, and alpha2C adrenergic receptor subtypes in whole tissue and alpha2A and alpha2C subtypes in cultured smooth muscle cells. Binding studies with [3H]RX821002 (a highly selective and specific ligand for alpha2-adrenergic receptor) in isolated membrane fractions of human corpus cavernosum smooth muscle cells, demonstrated specific alpha2-AR binding sites with high affinity (Kd = 0.63 nM) and limited capacity (25-30 fmol/mg protein). Binding of [3H]RX821002 was displaced with the nonselective alpha-AR antagonist, phentolamine, and with the alpha-AR agonist, norepinephrine, in a dose-dependent manner, but not by the selective alpha1-AR agonist, phenylephrine. Binding of [3H]rauwolscine was also displaced by phentolamine. UK 14,304, a selective alpha2-AR agonist, inhibited forskolin-induced cyclic adenosine monophosphate (cAMP) synthesis in cultured human corpus cavernosum smooth muscle cells and induced dose-dependent contractions of tissue strips in organ bath chambers. UK 14,304-induced contractions were inhibited with alpha2-AR selective antagonists, rauwolscine and delquamine (RS 15385-197). These observations suggest that in human corpus cavernosum, norepinephrine (NE) and epinephrine may activate postsynaptic alpha2-AR subtypes, in addition to activating alpha1-AR subtypes, on smooth muscle cells, contributing to local control of human corpus cavernosum smooth muscle tone, in vivo.     

Benign and malignant pediatric scrotal masses

Pediatric patients presenting with painless scrotal masses can be perplexing because of the long differential diagnosis. A careful plan based on the physical examination and sonogram findings localizes the mass to the testis or an extratesticular location. Sonography distinguishes solid from cystic lesions. Subsequent management is based on the location and nature of the mass. Intratesticular masses are assumed to be malignant, but testis-sparing surgery is possible in pediatric patients. Extratesticular cystic lesions are likely benign and are managed according to the specific diagnosis. Solid extratesticular lesions require exploration to establish the correct diagnosis.     

Survival of patients with congenital diaphragmatic hernia during the ECMO era: an 11-year experience

The pure TdI-1 polypeptide that blocks miniature endplate potentials (MEPPs) and abolishes or reduces endplate potentials (EPPs) below the action potential threshold was identified from the crude fraction of Tityus discrepans venom. The toxin is a potent reversible non-depolarizing muscle relaxant that blocks more than 95% of the EPP at a 2 microM (0.1 mg/ml) concentration. On a molar basis, TdI-1 is as potent as or more potent than many muscle relaxants since, at the concentration used, the toxin suppressed more than 95% of the EPP. Using matrix-assisted laser desorption time of flight (MALD-TOF) ionization mass spectrometry, TdI-1 was found to have an unusally large mol. wt for a scorpion toxin, close to 48,000. The N-terminal sequence of the first 23 residues of TdI-1 was also determined. The fragment differs from the N-terminal sequences of all 140 peptidic scorpion toxins found in the SWISSPROT and PIR databases using the search engine of the felix.EMBL-Heidelberg.de computer (European Molecular Biology Laboratory, Heidelberg, Germany.     

Monitoring of oral anticoagulant therapy in lupus anticoagulant positive patients with the anti-phospholipid syndrome

Introduction of the International Normalized Ratio (INR) has improved the standardization of laboratory control of oral anticoagulant therapy (OAT). However, it has been reported that misleading INR results can be obtained from OAT patients with lupus anticoagulant (LA). To investigate this claim, we studied 35 OAT patients, 14 of whom had anti-phospholipid syndrome (APS) with a documented LA. Attainment of anticoagulation was confirmed by chromogenic assay of factor VII and factor X. Prothrombin times were performed using eight thromboplastins (five derived from rabbit brain, two recombinant human tissue factor and one made from human placenta) with an International Sensitivity Index (ISI) of <1.40. When using the thromboplastin manufacturers' ISI there was a significant difference (ANOVA, P<0.0001) between INR results obtained with the eight reagents for both APS (average CV = 12.4%) and non-APS (average CV = 12.5%) patient groups. Variation using the eight thromboplastins was assessed by calculating the CV for each sample; these values were then pooled for each patient group to give the average CV for all samples with all reagents for the two patient groups. Results for both patient groups exhibited markedly reduced variation (APS group average CV = 6.5%, non-APS group average CV = 5.8%) when locally assigned ISI values were employed in the calculation of INRs. Our data does not support the suggestion that the INR may not reflect the true level of anticoagulation in the long-term warfarin-treated patient, in whom lupus anticoagulant was detected. However, there was strong evidence that thromboplastin use should be restricted to those clot detection systems for which the reagent's manufacturer has assigned an ISI, or local ISI assignment must be undertaken. The inappropriate use of a generic (i.e. optical or mechanical clot detection system without regard to specific analyser type) ISI value can lead to ambiguous results.     

Tracheal ligation: the dark side of in utero congenital diaphragmatic hernia treatment

This retrospective study investigates the clinical characteristics of gestational diabetes mellitus (GDM) (time of diagnosis, different treatment, metabolic parameters, etc.) in relation to prepregnancy body mass index (BMI) and the influence of BMI on neonatal outcome. 93 GDM women and 110 control subjects were divided into three groups in relation to their prepregnancy BMI: normalweight (Nw), overweight (Ow) and obese (Ob). GDM was diagnosed significantly (p < 0.01) earlier in Ow and Ob than in Nw. Preterm deliveries and cesarean sections resulted significantly (p < 0.01) increased in all BMI categories of GDM respect to matched controls. Prevalence of neonatal macrosomia was higher in GDM patients (44.6%) compared with normal controls (15.4%) and correlated (p < 0.01) with prepregnancy BMI in both groups. Nevertheless in each BMI category the prevalence of macrosomia was significantly higher in GDM patients. The body weight increase during pregnancy was not associated with neonatal macrosomia. This study shows that prepregnancy BMI is an important risk factor for GDM and is predictive for macrosomia specially in women suffering from GDM.     

Functional equivalence of native light-sensitive channels in the Drosophila trp301 mutant and TRPL cation channels expressed in a stably transfected Drosophila cell line

As we have pointed out in this article, a health care study should have a well-defined intent that is matched to the study type, population of interest, and outcome. Care must be taken to collect samples in a meaningful way, so that results can be generalized to larger populations. Outcomes must be selected carefully to ensure that they will be sensitive to the types of care being considered, and only a few main outcomes should be selected so as to preserve the level of statistical significance of the research results. Sample sizes should be sufficient to detect an effect of reasonable size, after accounting for attrition in longitudinal studies and rates of occurrence with dichotomous outcomes. If the study purpose is to compare multiple institutions or health care providers, statistical adjustments for case mix will generally be required. Outcome research is an expanding area of development for rheumatology care and for medical care in general. It offers the promise of the use of administrative data bases to answer questions that are important both to arthritis researchers and to consumers of rheumatology care. As with all areas of clinical research, we must maintain appropriate levels of statistical rigor to protect the integrity of the results. Inadequate attention to the design and analysis of data can compromise research results before a study even gets started, and health care research studies have as many potential statistical pitfalls as other types of clinical research.