Nasal transit time in normal subjects and pathologic conditions

A radionuclide method using Tc-99m was used to measure the nasal transit time in 43 patients, including normal smokers and nonsmokers and those with various nasal or paranasal pathologies. The technique described was slightly modified from that already in use in various centers in order to enable more precise measurement. Measurement of transit time of a droplet of Tc-99m phytate on the nasal mucosa appears to differentiate patients with immotile cilia syndrome from normal controls. A positive test, however, can occur also in smokers and in patients with other nasal and paranasal problems. The test is reproducible, cost-effective, and noninvasive, enabling the clinician to make a more appropriate selection of patients needing further investigation.     

Assessment of the spatial occurrence of childhood leukaemia mortality using standardized rate ratios with a simple linear Poisson model.

Reports of a suspected cluster of childhood leukaemia cases in West Central Phoenix have led to a number of epidemiological studies in the geographical area. We report here on a death certificate-based mortality study, which indicated an elevated rate ratio of 1.95 during 1966-1986, using the remainder of the Phoenix standard metropolitan statistical area (SMSA) as a comparison region. In the process of analysing the data from this study, a methodology for dealing with denominator variability in a standardized mortality ratio was developed using a simple linear Poisson model. This new approach is seen as being of general use in the analysis of standardized rate ratios (SRR), as well as being particularly appropriate for cluster investigations.     

Auditory Brain Stem Responses in Schizophrenic Patients

Auditory brain stem responses (ABR) were recorded from 20 schizophrenic patients, of whom ten were medicated and ten were unmedicated. A matched control group consisted of ten normal subjects. A statistically significant difference in the latencies of N3 and N5 recordings was found among the three groups. The results suggest that unmedicated schizophrenics have a delayed latency for peaks N3 and N5, and that medication (with neuroleptic drugs) shortens these delayed latencies back to the normal range.     

Stretched nanosecond pulses of a Q-switched Nd-YAG laser: Transmission through optical fibres and in vitro effects on human calcified tissues

Using a new Q-switched Nd-YAG laser prototype (1064 nm), every initial pulse (15 ns or 33 ns duration, 10 Hz repetition rate, 2×E energy, Pmax power) was transformed into two successive pulses (each one with 15 or 33 ns duration, 1×E energy) delayed by 27 ns. With a 15 ns initial pulse, the two 15 ns components (each one with Pmax/2) were well separated and called a 15 ns double pulse. When the duration of the initial pulse was stretched to 33 ns, the overlapping of the two 33ns components (each with Pmax/4) produced only one pulse trapezoidally shaped, of 60 ns duration and called 60 bi-pulse. With double pulses, it was possible to transmit 100 mJ through a silica-silica optical fibre of 400 μm diameter, whereas 155 mJ were transmitted with bi-pulses. Human calcified atheromatous tissues were irradiated with bi-pulses through a 200 μm diameter optical fibre. Craters (0.6–0.7 mm in diameter) were easily obtained in atheromatous aortic segment with 40 mJ energy per bi-pulse. No trace of carbonization was noticed. Fragmentation of urinary and biliary calculi was also obtained.     

Analysis of Arg834Gln and Val902Glu type 2A von Willebrand disease mutations: studies with recombinant von Willebrand factor and correlation with patient characteristics

Type 2A von Willebrand disease (vWD), the most common qualitative form of vWD, is characterized by a relative decrease in circulating intermediate and high molecular weight (HMW) multimers. We studied the biosynthesis of recombinant von Willebrand factor (vWF) containing each of two type 2A vWD mutations previously reported by us, Arg834Gln and Val902Glu. The structure of recombinant Arg834Gln vWF within transfected COS-7 cells and the secretion of HMW multimers were similar to wild type vWF. The normal transport and secretion of Arg834Gln vWF, categorizes it as a group II type 2A mutation. In contrast, the Val90- 2Glu mutation resulted in intracellular proteolysis of vWF with the generation of a 176-kD fragment and retention of vWF between the endoplasmic reticulum and the Golgi complex. Moreover, the 176-kD fragment was also increased in plasma from patients with the Val902Glu mutation. Significantly impaired secretion and intracellular proteolysis of Val902Glu vWF categorizes a new sub-group of type 2A mutations. The intracellular proteolysis of vWF Val902Glu explains the lack of response to 1-deamino 8-D-arginine vasopressin (DDAVP) in patients who carry the mutation.     

Anonymous HIV testing: the impact of availability on demand in Arizona.

The purpose of this study was to evaluate the impact of anonymous testing availability on human immunodeficiency virus (HIV) test demand in Arizona. Testing patterns before and after the introduction of anonymous testing were compared. Client knowledge of new test policy and delay in testing until an anonymous option was available were assessed. Test numbers among men who have sex with men showed a statistically significant increase after introduction of an anonymous testing option. Arizona continues to maintain anonymous testing availability. Public health agencies should consider how test policy may influence people's HIV test decisions.     

Antagonization of TNF attenuates systemic hemodynamic manifestations of envenomation in a rat model of Vipera aspis snakebite

OBJECTIVES: Tumor necrosis factor (TNF) has been reported as a mediator of local tissue injury following snake envenomation in an intact rat model. We investigated whether systemic release of TNF occurs following Vipera aspis envenomation. We further analyzed the possible connection between envenomation-related hemodynamic depression and TNF antagonization (TNF antibodies or soluble TNF receptor). DESIGN: A prospective, randomized, controlled experimental study using a rat model for snake envenomation. SETTINGS: A medical university hospital research laboratory. INTERVENTION: Eighty rats (300-400 g) were divided into four groups (n = 20): control and three experimental groups. Intramuscular injection of V. asis 500 microg/kg was administered to the three experimental groups: venom only (group 1), venom and 40 microg anti-TNF antibodies (group 2), venom and 250 microg soluble TNF receptor (p55-R; group 3). Hemodynamic parameters were monitored up to 4 h following venom injection. MEASUREMENTS AND RESULTS: A significant hemodynamic deterioration (reduction in heart rate and blood pressure) occurred 30 min following venom injection in group 1 compared to groups 2 and 3, where hemodynamic parameters remained stable throughout the 4 h observation period. Serum levels of TNF were detected 15 min after venom injection and peaked after 2 h at 485+/-12 pg/ml. CONCLUSIONS: The hemodynamic consequences of intramuscular injection of V. aspis venom can be blunted in a rat by systemic antagonization of TNF activity prior to venom injection. The poisonous hemodynamic effects of the V. aspis venom might be caused by systemic release of TNF.     

Phorbol-myristate-acetate-induced platelet aggregation in the presence of inhibitors

4 beta-Phorbol-12-myristate-13-acetate (PMA) at 100 ng/ml was able to induce platelet aggregation in the presence of agents which inhibited aggregation, triggered by other agonists such as adenosine diphosphate sodium salt (ADP), thrombin and collagen. PMA induced aggregation in acid-citrate-dextrose platelet-rich plasma. 100 microM tetracaine, 5 microM bromophenacyl bromide and 0.2 mM mepacrine decreased PMA-induced aggregation by only 10% in contrast to their high inhibitory effect on other aggregation systems. However, 0.4 mM mepacrine did inhibit PMA-induced aggregation at the same rate as the other aggregation systems. 100 mg/ml vincristine slightly affected PMA-induced platelet aggregation, whereas cytochalasin B rather enhanced it. Nordihydroguaiaretic acid, 5, 8, 11, 14-eicosatetraynoic acid and p-nitrophenyl-phosphorylcholine had no effect on PMA- or collagen-induced platelet aggregation, partially inhibited aggregation triggered by ADP and strongly inhibited aggregation caused by thrombin. It is suggested that PMA exerts its effect on platelets mainly due to its ability to alter their membranes.     

Prevalence of herpesviruses at onset of idiopathic nephrotic syndrome

Background

Idiopathic nephrotic syndrome (INS) is likely a primary immune disorder, but viruses might also be involved in the mechanisms of the disease. Here, we investigate the link between herpesvirus infection and the first manifestation of INS in children.

Methods

A prospective, multicentre, and population-based case–control study called NEPHROVIR included 164 patients, aged 6 months to 15 years old, newly diagnosed with INS, and 233 controls matched for gender, age, and period of sample. The analysis was done on 124 patients and 196 controls. Epstein–Barr virus (EBV), cytomegalovirus (CMV), human herpesvirus-6 (HHV-6), and human herpesvirus-7 (HHV-7) DNA prevalence at diagnosis were assessed from whole peripheral blood samples, as well as EBV and CMV viral load and seroprevalence.

Results

EBV DNA was significantly more prevalent in cases than in controls (50.8 vs 29.1 %; OR?=?2.6; p?=?0.0002), with no difference in viral load. A significant difference was also found for CMV (11.3 vs 3.6 %; p?=?0.02) and HHV-7 (83 vs 72 %; p?=?0.02) DNA prevalence between cases and controls. There were significantly more EBV and CMV recent infections or reactivations based on VCA-IgM and CMV IgM in cases than controls, while there were no differences in IgG seroprevalence.

Conclusion

The prevalence of positive EBV DNA detection and recent infection or reactivation is higher in children at onset of INS compared to a population matched for age, gender, and time of sampling.