Multicenter study assessing effects of heat and moisture exchanger use on respiratory symptoms and voice quality in laryngectomized individuals

OBJECTIVE: A multicenter study based in the United States assessed the heat-moisture exchanger effect on respiratory symptoms and "voice quality" of laryngectomees. PATIENTS AND MEASURES: The study group consisted of 81 consecutive laryngectomees (62 men and 19 women; mean age, 66 years; age range, 45 to 89 years), with a median follow-up of 3.5 years (range, 0.5 to 24 years). A structured questionnaire was used to assess 3-month results, and tally sheets recorded the frequency of cough-expectoration during first and last trial weeks. RESULTS: Compliance was 73% (n = 59); decrease in coughing, 68%; sputum production, 73%; forced expectoration, 60%; and need for stoma cleaning, 52% of these 59 patients. Regarding daily cough-expectoration frequency, a statistically significant decrease (P < 0.0001) was found between the first and last trial weeks. Regarding influence on voice quality, 46% of regular users reported improvement in intelligibility, 30% in loudness, 37% in fluency, and 40% in telephone intelligibility. Fourteen patients (19%) reported skin irritation, with discontinuation of 7 patients. CONCLUSION: The observed decrease in pulmonary symptoms and improvement in voice quality confirm earlier reports from the Netherlands, United Kingdom, and Spain indicating improvement in postlaryngectomy quality of life.     

Birthweight and risk of overall and cause-specific childhood mortality

Early life events have important short- and long-term consequences. It is clear from previous studies that birthweight is associated with infant mortality and with childhood and adult morbidities. However, few studies have focused on the relationship between birthweight and childhood mortality. To assess this relationship, we conducted a population-based case-control study of children born during 1968-96 in Washington state. Cases consisted of 6247 children who died at 1-19 years of age. A total of 31 074 controls were matched five to one to cases by birth year. Compared with children with a birthweight of 3000-3499 g, children with lower birthweights had a greater risk of childhood mortality. These lower birthweight children had increased risks of childhood deaths from infectious diseases, congenital anomalies, central nervous system diseases and heart disease, but not of deaths resulting from accidents, cancer, suicide or homicide. The magnitude of these risks differed somewhat by age. Our results suggest that birthweight exerts important influences on children's risk of age-specific and cause-specific mortalities, particularly those with a strong biological component.     

Evaluation of 2 scatter correction methods using a striatal phantom for quantitative brain SPECT

OBJECTIVE: Scatter correction is an important factor in quantitative SPECT. In this study, we evaluated 2 methods of scatter correction for brain SPECT. The first is based on thresholding the energy spectrum (ES), and the second is based on a modification of the transmission-dependent convolution subtraction (TDCS) method. METHODS: SPECT imaging of a skull striatal phantom was performed using a triple-head camera with and without scatter correction. The striatal compartments were filled with (123)I, and the brain shell cavity (background) was filled with varying concentrations of (123)I to obtain striatal-to-background ratios of 2, 5, 10, 15, 20, and 25 to 1, respectively, which were considered to be the expected ratios. SPECT-measured ratios of striatal-to-background counts were determined with scatter correction (both ES and TDCS methods) and without scatter correction and were then compared with the expected ratios. RESULTS: Without scatter correction, measured striatal-to-background ratios were underestimated by an average of 41.7%, compared with the expected ratios. The ES method of scatter correction underestimated the striatal-to-background ratios by an average of 27.4%, a significant improvement (P < 0.04) over those without scatter correction. With the TDCS method of scatter correction, the ratios were underestimated by only 3.3% (P < 0.03). TDCS ratios were significantly (P < 0.04) higher than ES ratios and were nearly identical to the expected ratios. CONCLUSION: These results suggest that scatter correction significantly improves the striatal-to-background ratios. The TDCS method appears to correct scatter more effectively than does the ES method for the striatal phantom, thus providing more accurate quantification.     

Multilineage cells from adipose tissue as gene delivery vehicles

We have characterized a population of mesenchymal progenitor cells from adipose tissue, termed processed lipoaspirate (PLA) cells, which have multilineage potential similar to bone marrow-derived mesenchymal stem cells and are also easily expanded in culture. The primary benefit of using adipose tissue as a source of multilineage progenitor cells is its relative abundance and ease of procurement. We examined the infection of PLA cells with adenoviral, oncoretroviral, and lentiviral vectors. We demonstrate that PLA cells can be transduced with lentiviral vectors at high efficiency. PLA cells maintain transgene expression after differentiation into adipogenic and osteogenic lineages after lentiviral transduction. Therefore, PLA cells and lentiviral vectors may be an efficient combination for use as a therapeutic gene delivery vehicle.     

Surfing for back pain patients: the nature and quality of back pain information on the Internet

STUDY DESIGN: A prospective, systematic review of web sites related to back pain. OBJECTIVE: To assess the nature and quality of back pain-related information on the World Wide Web during a 2-year period. SUMMARY OF BACKGROUND DATA: The Internet has become a rich source of medical information. Limited knowledge is available, however, about the quality of online resources. Although previous systematic reviews on medical-related web sites found problems in varying degrees with the credibility of information, no such review was conducted to assess the back pain-related sites. METHODS: A search of web sites was conducted in November 1996 using five search engines (AltaVista, Infoseek, Lycos, Yahoo, and Magellan) and two key terms ("back pain" and "back problems"). A sample of sites was evaluated by two independent reviewers. Each site was described by the type and nature of the sponsor, target audience, and content. Overall quality was assessed in terms of evidence-based information available. RESULTS: Seventy-four web sites were reviewed in 1996, and nine of them (12.2%) were identified as high-quality sites. Advertising was the focus of 80.8% of the sites. Eleven sites (14.9%) were found to be discontinued 1 year later, and 20 (27.0%) were not accessible by the reviewers at the 2-year follow-up evaluation. Of the remaining 54 sites, 44.4% were produced by for-profit companies, and most sites targeted people with back pain (63.0%). Only seven out of the nine high-quality sites held their ratings at the 2-year follow-up evaluation. CONCLUSION: Most back pain-related web sites can be classified as advertising. The quality varied considerably, resulting in difficulties for patients to find useful information in this field. The increasing number of people seeking medical information on the Web creates a need for more high quality sites. Further, systematic review of web sites should be encouraged to monitor the accuracy of Internet publication.     

Endocannabinoids protect cerebral cortical neurons from in vitro ischemia in rats

Activation of the ventrolateral periaqueductal gray (vlPAG) evokes a reaction of quiescence, immobility, hypotension and bradycardia. Pain of deep somatic or visceral origin also often triggers a reaction of quiescence, immobility, hypotension and bradycardia and further, evokes a selective increase in immediate-early-gene (c-Fos) expression within the vlPAG. Vasodepression evoked from the vlPAG is thought to be mediated by an inhibition of presympathetic neurons within the rostral ventrolateral medulla (RVLM). In this study the prior injection of retrograde tracer into the RVLM was combined with the use of Fos expression as a marker of neuronal activation, to determine if deep (muscle) pain-evoked vasodepression could be mediated by a direct vlPAG-RVLM pathway. It was revealed that intramuscular injection of formalin, in the anaesthetised rat, evoked a significant increase in Fos expression within the caudal vlPAG, and that approximately 25% of the Fos-immunoreactive neurons projected to the RVLM.     

Characteristics of substance-abusing persons with schizophrenia: the paradox of the dually diagnosed

Previous studies have noted the paradox of the dually-diagnosed (serious mental illness and substance abuse) in which the dually-diagnosed are judged to be both behaviorally more disorganized and simultaneously more socially competent. This study sought to further assess this paradox with a large sample size and a comprehensive assessment approach. In this study, the dually-diagnosed (N = 233) differed significantly from the non-dually-diagnosed (N = 262) in the symptom paradox. The dually-diagnosed were judged both more behaviorally disorganized and socially intact. The comprehensive assessment approach yielded empirical data in support of three possible hypotheses to explain the paradox. The implications of the findings and the three possible hypotheses are discussed.     

DNA patterns in parathyroid disease predict postoperative parathyroid hormone secretion

Flow cytometric analysis of the nuclear deoxyribonucleic acid (DNA) content of parathyroid glands excised from patients with hypercalcemic hyperparathyroidism has identified three distinct DNA patterns. The most frequent pattern showed a high percentage of cells with tetraploid DNA, which indicated an increase in the G2 and M phase of the cell cycle. Thirty-four patients were found to have abnormal tetraploid DNA content. One patient had a normal diploid pattern, and seven were found to have an aneuploid DNA population in their excised parathyroid glands. This unexpected finding of aneuploid DNA appears to be an unique feature of these endocrine glands because they have no histologic or clinical characteristics of malignant change. All patients have remained normocalcemic and clinically well after excision of only grossly enlarged glands. Postoperative parathyroid hormone (PTH) levels were correlated in 17 patients with DNA analyses of biopsy specimens from 30 normal-sized glands which were left in situ. Seven patients with elevated PTH postoperatively had high tetraploid or aneuploid DNA in all 13 glands from which biopsy specimens had high tetraploid or aneuploid DNA in all 13 glands from which biopsy specimens had been taken. In 10 patients with normal PTH levels, six had normal diploid patterns, whereas four had high tetraploid DNA in their gland biopsy specimens. DNA content present in biopsy specimens of normal-sized, in situ glands was predictive (p less than 0.042) of parathyroid gland secretory activity. These findings suggest that the stimulus for parathyroid gland hyperfunction often affects more than a single enlarged gland and persists after clinical cure, as shown by a more rapid cell turnover in some remaining glands and continued hypersecretion of hormone.