False-negative results by polymerase chain reaction due to contamination by glove powder

The polymerase chain reaction (PCR) technique has become an important, widely employed method for the detection and quantitation of the nucleic acid sequences used in the diagnosis and monitoring of genetic and infectious diseases. Much attention has been directed at the problem of false-positive PCR results, which are generally attributed to low-level laboratory contamination of amplified sequences ("carryover"). In contrast, few investigators have commented on the somewhat less frequent, but equally problematic, false-negative PCR results. Investigation of the source of sporadic false-negative PCR reactions found that glove powder, inadvertently introduced into tubes when gloves are changed in an effort to reduce false-positive results, can nonspecifically inhibit each of the major steps in the PCR detection process. Methodologic precautions are recommended to minimize this problem.     

Rehabilitation prognosis of aphasias of various etiologies with reference to clinical, neurolinguistic and computerized tomography findings

To obtain further insights into the rehabilitation outlook in different baseline conditions, a comparison was made of data and treatment outcomes in 92 patients having aphasias of different etiology and disease duration. Rating as "improved" was contingent on significant changes in at least 2 subtests of the AAT (Aachener Aphasietest), which is a fairly stringent requirement. This criterion was met by some 35% of the patients overall, independent of their age; the percentage increased to 45% in case of treatment onset during the first year, while in later onset, significant improvement was achieved in 15% only. Aphasic syndromes secondary to hemorrhage, trauma, tumors, or infections, usually are less severe than the predominant classical syndromes, i.e. Global, Broca and Wernicke aphasia, caused by ischemic stroke. CT lesion size did not yield any definite information. Minor improvements below the required significance levels, and, above all, gains in communication performance, i.e. further consolidation, could be achieved by appropriate management even after the crucial initial year, which, however, does not imply any fundamental changes in the rehabilitation prognosis as such.     

Persistence of post‐operative color Doppler abnormalities is linked to reduced graft survival in pediatric patients after liver transplantation

Color Doppler US is a readily available imaging modality for the evaluation of liver transplants. The aim of our study was to evaluate the temporal course of color Doppler US findings in children after LTX and to investigate the effect of resolving and persisting abnormalities during follow‐up on long‐term outcome. All children who underwent LTX during January 2000 until December 2003 (155 LTX in 137 patients, 75 male and 62 female; mean age at LTX 4.1 ± 4.8 years; range, 0.1‐16.3 years) were retrospectively evaluated. Following a predefined ultrasound protocol with prospective documentation, intraoperative, post‐operative, and follow‐up examinations were evaluated for color Doppler abnormalities. The time of occurrence and temporal course of the findings were recorded. Graft survival rates and graft survival times were compared. Abnormal color Doppler US examinations were noted in 98 of 155 grafts during the entire observational period (63.2%). In 57 of 98 grafts (58.2%), abnormalities were limited to the perioperative period (<30 days after LTX). Survival of grafts with transient perioperative abnormalities was similar to transplantations with regular color Doppler US examinations (graft survival rates, 80.7% vs 84.2%, P = .622; mean graft survival time, 2596.92 vs 2511.40 days, P = .67). Grafts with persisting color Doppler US abnormalities in the follow‐up period (>30 days after LTX; 37/98 LTX, 37.8%) showed reduced survival compared with regular courses (graft survival rate 62.2% vs 80.7%, P = .047), indicating underlying organ‐specific alterations. Standardized longitudinal evaluation during the perioperative and the follow‐up period can enhance the prognostic capabilities of color Doppler US in children following LTX.     

Oropharyngeal dysphagia in patients with multiple sclerosis: do the disease classification scales reflect dysphagia severity?

Multiple sclerosis is a neurological disease that involves swallowing disorders. Many studies have shown an association between neurological and swallowing performance, but results have been conflicting.ObjectiveTo identify the frequency of dysphagia in patients with multiple sclerosis and neurological indicators that can represent the performance of swallowing.MethodIn this study (cross-sectional) 120 Multiple Sclerosis patients underwent Functional Assessment of Swallowing by flexible nasal-pharyngo-laryngoscopy and the results were compared with the scores of the rating scales: (Clinical Evolving Forms of Disease, Functional Disability Scale for and Scale Systems Extended Functional Disability [Kurtzke Expanded Disability Status Scale]).ResultsDysphagia was found in 90% of patients. Among the clinical forms of the disease, the progressive forms (primary progressive and secondary progressive) were more frequently associated with severe dysphagia, while the relapsing-remitting form presented more often mild and moderate dysphagia. Regarding the Disability Scale for Functional Systems, cerebellar function, brainstem function and mental health were associated with dysphagia, especially in the severe form. Regarding the Extended Functional Disability Scale, higher scores were associated with severe dysphagia.ConclusionDysphagia is common in MS patients, especially in those with greater impairment of neurological functions.     

Bovine colostrum ameliorates diarrhea in infection with diarrheagenic Escherichia coli, shiga toxin-producing E. Coli, and E. coli expressing intimin and hemolysin.

BACKGROUND: Diarrheagenic Escherichia coli may cause serious extraintestinal complications, but there is no specific treatment. METHODS: Patients with diarrhea caused by diarrheagenic E. coli, specifically Shiga toxin-producing E. coli and E. coli-expressing intimin and enterohemorrhagic E. coli-hemolysin were treated by administration of pooled bovine colostrum, rich in antibodies to Shiga toxin and enterohemorrhagic E. coli-hemolysin, in a placebo-controlled, double-blind study. Symptom resolution and fecal excretion of infecting strains were assessed. RESULTS: No side effects were attributable to colostrum. Stool frequencies in the group treated with bovine colostrum were significantly reduced compared with those in the placebo group. No effect of therapy on the carriage of the pathogens or on complications of the infection could be demonstrated. CONCLUSIONS: Bovine colostrum is well tolerated and diminishes frequency of loose stools in children with E. coli-associated diarrhea. A prospective study should be conducted among a larger number of children with Shiga toxin-producing E. coli identified early in illness, to determine the effectiveness of colostrum therapy.     

Congenital colonic hypoganglionosis in murine trisomy 16--an animal model for Down's syndrome.

Human trisomy 21 (Down's syndrome) affects the development of multiple organ systems frequently including gastrointestinal anomalies such as Hirschsprung's disease. To elucidate the underlying morphogenetical mechanisms a murine model (trisomy 16 mouse) for Down's syndrome has been established. However, previous studies on trisomy 16 (TS 16) mice have been confined to non-enteric developmental disorders. Therefore, the aim of the present study was to assess the enteric nervous system and the morphology of the terminal colon in TS 16 mice during late intrauterine development. Immunohistochemical examination (protein gene product 9.5) revealed a reduction of myenteric ganglionic size and density as well as the presence of ectopic ganglia, thus resembling typical features of colonic hypoganglionosis and myenteric heterotopia. Enzyme histochemistry for NADPH-diaphorase showed a remarkable decrease of NADPH-positive neurons in TS 16 mice, whose sparse distribution was confined to a minor portion of the oligoneuronal myenteric ganglia. Electron microscopical studies of TS 16 mice confirmed the myenteric hypoganglionosis and, additionally, demonstrated the absence of submucosal neurons. Whereas neurons of controls were characterized by arborizing neuronal processes, neurons of TS 16 mice were reduced in size and exhibited only few and shortened cytoplasmic protrusions. Additionally, prominent bundles of parallel nerve fibers passed through the intermuscular zone and lacked the arborization pattern of normal neuropil. They were not observed in controls and resembled features of extrinsic nerves. Approximately one third of TS 16 mice developed a colonic dilatation proximally to an obstructed segment characterized by a pronounced hypoganglionosis. Although TS 16 mice did not develop complete aganglionosis, the abundance of nerve fiber bundles and the colonic dilatation were consistent with the morphological characteristics of Hirschsprung's disease. The findings suggest that even a hypoganglionosis characterized by ultrastructurally altered and NADPH-diaphorase-deficient neurons may be capable of provoking a functional intestinal obstruction. Similar abnormalities of the enteric nervous system as observed in TS 16 mice may also be present in such trisomy 21 patients who suffer from chronic intestinal motility disorders which are not caused by complete aganglionosis.     

Identities and frequencies of mutations of the otoferlin gene (OTOF) causing DFNB9 deafness in Pakistan

Mutations in OTOF , encoding otoferlin, cause non-syndromic recessive hearing loss. The goal of our study was to define the identities and frequencies of OTOF mutations in a model population. We screened a cohort of 557 large consanguineous Pakistani families segregating recessive, severe-to-profound, prelingual-onset deafness for linkage to DFNB9 . There were 13 families segregating deafness consistent with linkage to markers for DFNB9 . We analyzed the genomic nucleotide sequence of OTOF and detected probable pathogenic sequence variants among all 13 families. These include the previously reported nonsense mutation p.R708X and 10 novel variants: 3 nonsense mutations (p.R425X, p.W536X, and p.Y1603X), 1 frameshift (c.1103_1104delinsC), 1 single amino acid deletion (p.E766del) and 5 missense substitutions of conserved residues (p.L573R, p.A1090E, p.E1733K, p.R1856Q and p.R1939W). OTOF mutations thus account for deafness in 13 (2.3%) of 557 Pakistani families. This overall prevalence is similar, but the mutation spectrum is different from those for Western populations. In addition, we demonstrate the existence of an alternative splice isoform of OTOF expressed in the human cochlea. This isoform must be required for human hearing because it encodes a unique alternative C-terminus affected by some DFNB9 mutations.     

Relationship of CD146 expression to secretion of interleukin (IL)‐17, IL‐22 and interferon‐γ by CD4+ T cells in patients with inflammatory arthritis

Expression of the adhesion molecule, CD146/MCAM/MelCAM, on T cells has been associated with recent activation, memory subsets and T helper type 17 (Th17) effector function, and is elevated in inflammatory arthritis. Th17 cells have been implicated in the pathogenesis of rheumatoid arthritis (RA) and spondyloarthritides (SpA). Here, we compared the expression of CD146 on CD4⁺ T cells between healthy donors (HD) and patients with RA and SpA [ankylosing spondylitis (AS) or psoriatic arthritis (PsA)] and examined correlations with surface markers and cytokine secretion. Peripheral blood mononuclear cells (PBMC) were obtained from patients and controls, and synovial fluid mononuclear cells (SFMC) from patients. Cytokine production [elicited by phorbol myristate acetate (PMA)/ionomycin] and surface phenotypes were evaluated by flow cytometry. CD146⁺CD4⁺ and interleukin (IL)‐17⁺CD4⁺ T cell frequencies were increased in PBMC of PsA patients, compared with HD, and in SFMC compared with PBMC. CD146⁺CD4⁺ T cells were enriched for secretion of IL‐17 [alone or with IL‐22 or interferon (IFN)‐γ] and for some putative Th17‐associated surface markers (CD161 and CCR6), but not others (CD26 and IL‐23 receptor). CD4⁺ T cells producing IL‐22 or IFN‐γ without IL‐17 were also present in the CD146⁺ subset, although their enrichment was less marked. Moreover, a majority of cells secreting these cytokines lacked CD146. Thus, CD146 is not a sensitive or specific marker of Th17 cells, but rather correlates with heterogeneous cytokine secretion by subsets of CD4⁺ helper T cells.     

Shoulder pain in the adolescent athlete: a multidisciplinary diagnostic approach from the medical, surgical, and imaging perspectives

This article is a compilation work authored by a pediatric radiologist, primary care pediatric sports medicine physician and pediatric orthopedic surgeon with the goal of providing a simplified diagnostic approach to the adolescent athlete presenting with shoulder pain. The spectrum of complex diagnoses often confused by innumerable radiologic acronyms can be distilled into common recognizable injury patterns. Once the physiology leading to the injury pattern is understood, the pediatric radiologist can perform a more focused imaging approach and provide a more meaningful interpretation to the referring orthopedic specialist.