Telemedicine: a useful tool for the pediatric cardiologist.

OBJECTIVE: To determine if the Georgia Statewide Academic and Medical System Telemedicine Network can deliver subspecialty pediatric care to rural areas of Georgia. MATERIALS AND METHODS: A retrospective review was conducted of a clinical experience, over a 30-month period from November 1993 through June 1996, involving 13 pediatric cardiology-related encounters in seven male and six female patients. Patients' ages ranged from 5 days to 16 years. Eleven encounters were initiated because of a suspicion of congenital heart disease (CHD); two encounters involved postoperative evaluations in patients who had recently undergone cardiac surgery at the Medical College of Georgia (MCG). RESULTS: Of the 11 patients suspected to have CHD, five had CHD documented during the telemedicine evaluation, of whom two were transferred to MCG for further invasive evaluation and surgical correction. Three others with CHD, and the remaining six patients who required no further subspecialty follow-up, were followed in their home communities by their primary care physicians. CONCLUSIONS: Telemedicine is a useful tool for the evaluation of infants and children with suspected CHD.     

Toward the development of a clinically useful approach to psychotherapy research

The controversial move toward the development of a consensus on evidence-based or empirically supported therapies may be seen as an international crisis facing psychotherapists. Researchers long have complained that practicing therapists all too often continue to guide what they do therapeutically on the basis of their clinical experience and not the available research findings. Practicing therapists long have complained that therapy research bears only a remote resemblance to what goes on in actual clinical practice and that research reports are written for other researchers, not for clinicians. In the hope of turning our current crisis into an opportunity, this panel involved a dialogue that was designed to bridge this clinical-research gap.     

Multicriteria fuzzy assignment method: a useful tool to assist medical diagnosis

The aim of this paper is to provide a concise portrayal of medical applications of a new fuzzy classification method called PROAFTN, which uses a multicriteria decision aid approach. The review summarises and discusses medical applications of the proposed method in acute leukemia, astrocytic and bladder tumours. Although still an investigative method, the preliminary results are very encouraging and demonstrate the potential performances of this procedure for solving medical classification problems.     

Hepatitis C virus phylogeny: a useful clinical tool

In order to type 45 recent isolates of Hepatitis C virus (HCV) originating from four different geographic regions of the world, we performed phylogenetic analysis of a 192 nucleotides (nts) long sequence from the 5'non-coding region (5'-NCR) of the virus genome and compared them with 55 HCV isolates/strains of known type. The results of this study showed that phylogenetic studies can assign an HCV isolate to the correct type in 100% and to the correct subtype in 98%. A comparison ofthis method with other methods using commercial kits revealed that it is appropriate for clinical use and is cost effective.     

The serum D-xylose test as a useful tool to identify malabsorption in rats with antigen specific gut inflammatory reaction

The inappropriate immune response to foods, such as peanut, wheat and milk may be the basis in the pathogenesis of enteropathies like coeliac and Crohn disease, which present small intestinal malabsorption. A number of recent studies have utilized d -xylose absorption as an investigative tool to study small intestinal function in a variety of clinical settings. Thus, the aim of this experimental study was to evaluate the intestinal absorption of d -xylose in an antigen-specific gut inflammatory reaction rat model. Animals of the experimental group were inoculated with peanut protein extract before their exposure to a challenge diet containing exclusively peanut seeds to induce the gut inflammatory reaction caused by peanut allergy. Our results show that systemic inoculation with peanut protein extract renders significantly higher antibody titres (5.085 ± 0.126 units) ( P  < 0.0001) than control rats (0.905 ± 0.053 units) and that the antibody titres correlate positively to an inflammatory alteration of the gut morphology ( P  < 0.0001). Animals pertaining to the experimental group showed an intestinal absorption of d -xylose lower than control rats ( P  < 0.0001). We also observed that d -xylose absorption correlates negatively with IgG titres and positively with morphometric parameters (Pearson correlation). In conclusion, the use of serum d -xylose test was useful to identify the presence of small intestinal malabsorption in our antigen specific gut inflammatory reaction rat model.     

A molecular gram stain using broad range PCR and pyrosequencing technology: a potentially useful tool for diagnosing orthopaedic infections.

The bacteria associated with orthopaedic infections are usually common gram-positive and gram-negative bacteria. This fundamental grouping of bacteria is a necessary first step in the selection of appropriate antibiotics. Since polymerase chain reaction (PCR) is more rapid and may be more sensitive than culture, we developed a postamplification pyrosequencing method to subcategorize bacteria based on a few nucleotide polymorphisms in the 16S rRNA gene. We validated this method using well-characterized strains of bacteria and applied it to specimens from spinal surgery cases with suspected infections. Lysates of 114 bacteria including 75 species were created following standard cultivation to obtain DNA. The DNA was amplified by a broad-range real-time PCR. The amplicons were evaluated by pyrosequencing and were classified as gram-positive, gram-negative, or acid-fast bacilli based on the first three to five nucleotides sequenced. In addition, clinical cases of suspected infection were obtained from spinal surgery. The results of the "molecular Gram stain" were compared with the results of traditional Gram stain and culture. The lysates of 107 (93.9%) of the bacteria extracts tested were appropriately categorized as gram-positive and gram-negative or as acid-fast bacilli on the basis of this assay. The sensitivity and specificity of this assay were 100% and 97.4% for gram-positive and 88.3% and 100% for gram-negative isolates. All of the five clinical samples were appropriately categorized as containing gram-positive or gram-negative bacteria with this assay. This study demonstrates that high sensitivity and specificity of a molecular gram stain may be achieved using broad-range real-time PCR and pyrosequencing.     

Semiquantitative multiplex PCR: a useful tool for large rearrangement screening and characterization

Methods presently employed for detection of large rearrangements have several drawbacks, such as the amount of sample and time required, technical difficulty, or the probability of false-negative carriers. Using the low-density-lipoprotein receptor (LDLR) gene, whose mutations are responsible for familial hypercholesterolemia (FH), we have developed a procedure to detect large rearrangements in this gene based on semiquantitative PCR, with important improvements as compared to previous methods. Our method covers the complete LDLR gene and introduces an internal control in the reaction. The procedure discriminates the four different large rearrangements (two deletions and two insertions) that we have used as positive mutation controls (Valencia-1 to -5). All altered exons from each rearrangement are identified. Furthermore, when families from probands carrying these large rearrangements (34 members) were analyzed, our results agreed with those obtained previously with Southern blot. We have also analyzed a sample of 110 unrelated FH probands and the method has correctly identified the two different large rearrangements present and insertions or deletions as small as 1 bp. In conclusion, the method we present allows the identification of large rearrangements affecting exons of the gene, including small insertions or deletions or complete gene deletion. In addition, it constitutes a first characterization step of rearrangements, and is easy to carry out fast, and can be applied to the analysis of any gene.     

Lentiviral vector: a useful tool for transduction of human liver endothelial cells

Endothelial cells play multiple roles in pathophysiologic processes and are increasingly being recognized as target cells of gene therapy. Lentiviral vectors derived from human immunodeficiency virus type 1 have an ability to infect both dividing and nondividing cells and currently receive a great deal of attention as an innovative tool for transduction of target cells. The purpose of the present work was to evaluate the efficacy of a lentiviral vector for transducing human liver endothelial cells (HLECs) in vitro. For the present study, a pseudotyped lentiviral vector encoding a green fluorescent protein (GFP) gene, LtV-GFP, was generated by means of FuGENE 6 method and allowed to infect HLECs. Approximately 95% of HLECs were positive for GFP expression after LtV-GFP infection at a multiplicity of infection of 10. Notably, LtV-GFP transduced HLECs had stable and long term GFP expression, showed gene expression of endothelial markers including CD 34, factor VIII, flt-1, KDR/flk-1 and HGF, and maintained in vitro angiogenic potential in a Matrigel assay to the same extent as primarily cultured HLECs. These findings provide evidence that lentivirus based gene delivery is an efficient tool for transduction of endothelial cells that could be considered for cell and gene therapies and hybrid artificial organs.     

Saliva electrolytes as a useful tool for anaerobic threshold determination

The purpose of the present study was to determine the anaerobic threshold by analysis of changes in saliva composition during an incremental exercise test on a cycle ergometer. Thirteen healthy males underwent a submaximal test with an initial load of 50 W and load increases of 50 W per 3 min, until capillary blood lactate exceeded 4 mmol · l^–1. A maximal test for maximum O₂ uptake (VO_2max) determination (initial load of 100 W and load increases of 50 W per 2 min) was also performed. Saliva and blood samples were obtained only in the submaximal test. Saliva threshold (Th_sa) was defined as the point at which the first increase in either Cl^– or Na⁺ occurred. Catecholamine threshold (Th_ca) was defined as the point at which a nonlinear increase occurred in either adrenaline or noradrenaline. The lactate (Th_la) and ventilatory (Th_ve) thresholds were determined according to published criteria. No significant differences were found between Th_sa values and the other methods of threshold determination. A high correlation was found between Th_sa and Th_la (r = 0.82, P < 0.01), and Th_sa and Th_ca (r = 0.75, P < 0.05). These results support the validity of Th_sa as a new method for noninvasive determination of the anaerobic threshold.     

A hybrid tabu search algorithm for automatically assigning patients to beds

ObjectiveWe describe a patient admission scheduling algorithm that supports the operational decisions in a hospital. It involves efficiently assigning patients to beds in the appropriate departments, taking into account the medical needs of the patients as well as their preferences, while keeping the number of patients in the different departments balanced.MethodsDue to the combinatorial complexity of the admission scheduling problem, there is a need for an algorithm that intelligently assists the admission scheduler in taking decisions fast. To this end a hybridized tabu search algorithm is developed to tackle the admission scheduling problem. For testing, we use a randomly generated data set. The performance of the algorithm is compared with an integer programming approach.Results and conclusionThe metaheuristic allows flexible modelling and presents feasible solutions even when disrupted by the user at an early stage in the calculation. The integer programming approach is not able to find a solution in 1 h of calculation time.     

On-line clearance: a useful tool for monitoring the effectiveness of the reuse procedure

Reprocessing of a dialyzer for repeated use in the same patient is widely practiced. The dialyzer fiber bundle volume (FBV) is monitored as an indicator of the dialyzer's suitability for continued use, with standards for reprocessed dialyzers requiring a FBV of greater than 80% of a new dialyzer to be maintained. We have used on-line measurement of clearance of sodium (OLC module, Fresenius Medical Care, Walnut Creek, CA) to assess small molecule clearance changes during and between treatments for a group of 29 chronic hemodialysis patients who reused high flux polysulfone dialyzers (F80, Fresenius Medical Care, Lexington, MA) reprocessed using citric acid and heat (95 degrees C). Data pertaining to the initial, 5th, 10th, and 15th uses were analyzed and showed that, within a single dialysis session, there was a trend for the clearance to reduce throughout the treatment (p < 0.001). Overall, there was also a trend for clearances to decline with increasing number of reuses (p < 0.008). Changes in FBV occurred, but such changes remained within the guidelines suggested by standards. It is concluded that on-line clearance measurements provide a simple noninvasive method to monitor dialyzer performance over each use and between uses.     

Prospective study of a real-time PCR that is highly sensitive, specific, and clinically useful for diagnosis of meningococcal disease in children

Due to the early administration of antibiotics, meningococcal disease is increasingly difficult to diagnose by culturing. Laboratory studies have shown PCR to be sensitive and specific, but there have been few clinical studies. The objectives of this study were to determine the diagnostic accuracy and clinical usefulness of meningococcal PCR through a prospective comparison of real-time PCR, nested PCR, and standard culturing of blood and cerebrospinal fluid (CSF). The setting was a tertiary-care pediatric hospital in Australia, and the participants were 118 children admitted with possible septicemia or meningitis. The main outcome measures-sensitivity, specificity, and positive and negative predictive values-were compared to a "gold standard " fulfilling clinical and laboratory criteria. For 24 cases of meningococcal disease diagnosed by the gold standard, culturing of blood or CSF was positive for 15 (63%), nested PCR was positive for 21 (88%), and real-time PCR was positive for 23 (96%). The sensitivity, specificity, and positive and negative predictive values of real-time PCR (the most sensitive test) for all specimens were, respectively, 96% (95% confidence interval, 79 to 99%), 100% (95% confidence interval, 96 to 100%), 100% (95% confidence interval, 85 to 100%), and 99% (95% confidence interval, 94 to 100%). Of 54 patients with suspected meningococcal disease at admission, 23 had positive PCR results. Only one PCR specimen was positive in a patient thought unlikely to have meningococcal disease at admission. Blood PCR remained positive for 33% of patients tested at up to 72 h. Real-time PCR has high positive and negative predictive values in this clinical setting, with better confirmation of cases than nested PCR. Targeting patients for PCR based on admission criteria appears to be practical, and the test may remain useful for several days after the start of antibiotic administration.     

Prenatal exome sequencing: A useful tool for the fetal neurologist

Prenatal exome sequencing (pES) is a promising tool for diagnosing genetic disorders when structural anomalies are detected on prenatal ultrasound. The aim of this study was to investigate the diagnostic yield and clinical impact of pES as an additional modality for fetal neurologists who counsel parents in case of congenital anomalies of the central nervous system (CNS). We assessed 20 pregnancies of 19 couples who were consecutively referred to the fetal neurologist for CNS anomalies. pES had a diagnostic yield of 53% (10/19) with most diagnosed pregnancies having agenesis or hypoplasia of the corpus callosum (7/10). Overall clinical impact was 63% (12/19), of which the pES result aided parental decision making in 55% of cases (6/11), guided perinatal management in 75% of cases (3/4), and was helpful in approving a late termination of pregnancy request in 75% of cases (3/4). Our data suggest that pES had a high diagnostic yield when CNS anomalies are present, although this study is limited by its small sample size. Moreover, pES had substantial clinical impact, which warrants implementation of pES in the routine care of the fetal neurologist in close collaboration with gynecologists and clinical geneticists.