Comparison of the Radiation Therapy Oncology Group recursive partitioning classification and Union Internationale Contre le Cancer TNM classification for patients with head and neck carcinoma

BACKGROUND: Prognostic models need to be tested in external validation studies to assess generalizability. Recursive partitioning analysis (RPA), a prognostic system based on the creation of a classification tree, has been proposed as a classification method in patients with head and neck carcinoma. The aim of this study was to compare the RPA and Union Internationale Contre le Cancer (UICC) TNM classification systems in patients with head and neck carcinoma treated consecutively in a single center. METHODS: A total of 2166 patients with carcinomas of the oral cavity, oropharynx, hypopharynx, and larynx was classified according to both the RPA and the TNM classification systems, and the results were compared. The endpoints considered were observed survival and survival free of locoregional tumor. The two methods of classification were evaluated objectively by use of measures of intrastage homogeneity (hazard consistency), interstage heterogeneity (hazard discrimination), predictive power (outcome prediction), and patient distribution between stages (balance). RESULTS: When the endpoint considered was observed survival, there were no clinically relevant differences between the two classifications. However, when the endpoint was locoregional control, the RPA system was sensitive to the type of treatment used, and it was not generalizable. CONCLUSIONS: To evaluate generalizability, new classification proposals need external validation studies that objectively measure the quality of the model. The performance of the RPA system was not reproducible in our cohort of patients when the endpoint evaluated was locoregional control.     

Cervical muscles weakness in chronic whiplash patients

BACKGROUND: Isometric cervical strength has been used for assessing the severity of cervical spine pathologies. However there is a conspicuous dearth of information relating to cervical strength data in patients suffering from chronic whiplash. Therefore the objective of this study was to compare absolute and ratio-based isometric cervical strength scores in chronic whiplash patients with reported corresponding scores in healthy subjects. METHODS: Isometric cervical strength was measured in the directions of flexion, extension, right and left lateral flexion in 97 patients, 51 women and 46 men, using a wall-mounted dynamometer. FINDINGS: Compared to published values of normal subjects, whiplash patients suffered sharp reductions of about 90% in both genders and in all directions. The consistency of the isometric cervical strength scores as indicated by the mean coefficient of variation was relatively low, 17% and 20% in men and women respectively. The flexion/extension strength ratio ranged 0.8--0.9, slightly higher than the reported range for normal subjects. This ratio was highly correlated (r=0.91, P=0.01) with the mean coefficient of variation in a subgroup of 9 patients. INTERPRETATION: In the absence of an obvious reason such as sever atrophy or grossly dysfunctional neurological control the indicated weakness of the cervical muscles may be associated with learned pain avoidance behavior which is typical among this group of patients.     

Cellular response in humans following vaccination with gripax influenza virus

Cellular response of peripheral blood lymphocytes to influenza antigens was measured in a group of young nurse-student volunteers (17–24 years old), following vaccination with a formol-inactivated trivalent influenza vaccine (Gripax). Cord blood lymphocytes (controls) did not react with any of the antigens. This excluded the possibility of any nonspecific mitogenicity of viral antigens. Viability of the cells was indicated by their responsiveness to phytohemagglutinin (PHA). Prior to immunization antigenic recognition to circulating strains (A/England (H₃N₂) and B/Hong Kong) was found in about 44% of the vaccinees; recognition of the recent strain A/USSR (H₁N₁) was found in only 10.5%. Following vaccination, approximately 80% of the subjects exhibited cellular response to all three vaccine strains. This includes the negative subjects, who showed an approximate 70% rate of conversion. There was no correlation between the antibody state and cellular response prior to and following vaccination as gathered from matched data of each participant.     

Gamma hydroxybutirate use for sexual assault

The use of gamma hydroxybutyrate (GHB) as a recreational drug has quickly spread among European young people during the past decade. Although it has been claimed that GHB can be potentially used to facilitate sexual assault, no case reports have been previously described. A case is described in which GHB was used with that criminal purpose and a review of previous literature is undertaken.     

Relationship between low back pain in post-menopausal women and mineral content of lumbar vertebrae

Until recently, chronic low back pain in post-menopausal women was commonly attributed to osteoporosis. This opinion has since been challenged on many counts, but controversy persists. The objective of this study was to examine this relationship. In 67 post-menopausal women, the mineral content of the lumbar vertebrae was measured by dual-energy X-ray absorptiometry and the age-normalized bone mineral index (ANBMI), the Z-score, was determined. Mean ANBMI in 40 subjects who complained of chronic low back pain (Group 1) was compared with mean ANBMI in the 27 who did not (Group 2). Pain intensity and related disability were quantified using standard questionnaires. Their respective correlations with ANBMI index and age at onset of menopause were examined. Correlation coefficients and significance of group differences were examined by appropriate statistical methods. The results showed that the mean ANBMI in Group 1 subjects was 96.5 +/- 16.9%, in Group 2 subjects it was 88.6 +/- 10.0%. Neither pain intensity nor disability was correlated with ANBMI. A weak but significant positive correlation was noted between body mass index and intensity of low back pain (r = 0.37; P < 0.05). The occurrence and severity of chronic low back pain in post-menopausal women, and the disability thereof, appear to be unrelated to the mineral content of lumbar vertebrae.     

Secondary neurologic deficit due to unrecognized spine instability in multitrauma casualties: a report of three cases

We present three cases of major multiple injuries in which delayed diagnosis of spinal instability resulted in neurologic deficit. The spinal injuries, once diagnosed, were treated by urgent surgical stabilization, which resulted in prompt and full recovery. A set of recommendations is proposed to prevent these potentially disastrous consequences.     

Ocular manifestations in Dengue fever

PURPOSE: To report a case of Dengue fever resulting in permanent visual loss in both eyes due to retinal capillary occlusion. METHODS: Case report. RESULTS: Severe permanent visual loss occurred in a patient with Dengue fever. Dilated fundus exam showed vascular sheathing with associated retinal hemorrhages at the equator and cotton wool spots in the maculae of both eyes. Fluorescein angiography revealed areas of capillary nonperfusion at the equator and in the macula. The diagnosis of Dengue fever was confirmed by serology detecting IgM antibodies to the Dengue virus. CONCLUSION: Ocular abnormalities may be seen in patients with Dengue fever, therefore ophthalmoscopy should be performed in patients presenting with severe forms of the disease.     

Carbamoylphosphonates, a new class of in vivo active matrix metalloproteinase inhibitors. 1. Alkyl- and cycloalkylcarbamoylphosphonic acids

Matrix metalloproteinases (MMPs) are a family of over 20 zinc-dependent enzymes that hydrolyze connective tissue and are involved in a variety of diseases, which are associated with undesired tissue breakdown. This paper reports the synthesis, characterization, and biological evaluation of a novel class of MMP inhibitors based on the carbamoylphosphonic acid function. We report a series of 10 open chain N-alkylcarbamoylphosphonic acids (ranging from R = C(1) to C(6) groups), eight N-cycloalkylcarbamoylphosphonic acids (ranging from cyclopropyl to cyclooctyl rings), and four N,N-dialkylcarbamoylphosphonic acids. The compounds were evaluated in three in vitro models, which consisted of (a) the in vitro invasion across a reconstituted basement membrane, (b) determination of the IC(50) values on recombinant MMP-1, MMP-2 MMP-3, MMP-8, and MMP-9 enzymes, and (c) an in vitro capillary formation model, which is a model of angiogenesis. Several of the compounds were also tested in an in vivo murine melanoma model. The following general conclusions have been reached: Most compounds show selectivity for MMP-2 over the other MMP subtypes examined. Cycloalkylcarbamoylphosphonic acids are more potent than comparable open-chain alkyl compounds. Optimal activity against MMP-2 among the cycloalkyl derivatives was shown by N-cyclopentylcarbamoylphosphonic acid (3m). N,N-Dialkylcarbamoylphosphonic acids that were examined showed weak or no activity. The compounds examined showed toxic effects neither in vitro nor in vivo in the concentrations used. Carbamoylphosphonic acids are water soluble at physiological pH and are stable indefinitely.     

Baroreflex control of renal sympathetic nerve activity and spontaneous rhythms at Mayer wave's frequency in rats

The effects of sedation with pentobarbital sodium (15 mg/kg followed by 15.9+/-1.2 mg/kg/h, i.v.) on arterial pressure (AP) Mayer waves and accompanying oscillations of renal sympathetic nerve activity (RSNA) were examined in rats (n=8). As compared with values observed in the conscious state, pentobarbital significantly (P<0.05) decreased AP (from 119+/-2 to 93+/-3 mm Hg), heart rate (HR; from 427+/-11 to 355+/-11 beats/min) and RSNA (from 1.20+/-0.27 to 0.62+/-0.13 microV). The baroreflex control of RSNA was analyzed by fitting a sigmoid logistic function to changes in RSNA and AP observed during nitroprusside and phenylephrine administrations. During pentobarbital infusion, the RSNA-AP relationship was reset towards lower AP values, but neither its maximum gain nor its gain at resting AP were significantly altered (from 6.3+/-1.0 to 5.8+/-1.4 and from 3.2+/-0.5 to 3.8+/-1.3 normalized units (n.u.)/mm Hg, respectively). Spectral power in the frequency band containing Mayer waves (0.29-0.73 Hz) was significantly decreased by pentobarbital for both AP (from 4.65+/-0.90 to 0.95+/-0.25 mm Hg2) and RSNA (from 1437+/-245 to 488+/-79 n.u.2). This effect was mainly secondary to the attenuation of strongly coherent oscillations of both variables at approximately 0.4 Hz. Although previous experimental evidence points to a major involvement of the sympathetic limb of the arterial baroreceptor reflex in the genesis of Mayer waves, the present study indicates that the amplitude of these oscillations cannot be used as a quantitative index of sympathetic baroreflex sensitivity.