Immunosuppression induced by respiratory viruses (influenza virus, adenovirus) in mice

The influence of respiratory viruses (adenovirus, influenza virus) on humoral immune response to heterologous T-dependent and T-independent antigens was studied. It was shown that inoculation of mice by the influenza virus (A/PR8/34-A/PR/8) 3 days before sheep red blood cells administration led to the inhibition of antibody forming cell (AFC) and immunoglobulin, forming cell (IFC) increase on 69% and 59% respectively. Adenovirus type 6 induced the similar suppression of AFC and IFC formation. Thus, viruses induced immuno-suppression, which was polyclonal. It was also shown that virus of one strain (type) could inhibit immune response to another strain (type) of virus. The immune response to T-independent antigen was not suppressed. The virus-induced immunosuppression was dependent on: 1) the infectivity of respiratory viruses, 2) the route of virus and heterologous antigen injection, and 3) the interval between the viruses and antigen inoculation.     

Recruitment of stock of deepwater redfish <Emphasis Type="Italic">Sebastes mentella</Emphasis> (Scorpaeniformes,Scorpaenidae) in the pelagial of the Irminger Sea and adjacent waters

Results of comparative analysis of several ecologo-populational characteristics and fauna of parasites of deepwater redfish Sebastes mentella from the pelagial of the Irminger Sea and slopes of Greenland are provided. It was established that the nursery area of the species in this part of the northern Atlantic is located in the shelf and shallow-water sites of the Greenland slopes. Near the nursery area, at deepwater sites of the Greenland slope, aggregations of mainly immature specimens (68–86%) with an average length of 35–38 cm are located, and, in the oceanic pelagial, there are mainly mature specimens (91–95%) with a length of more than 30 cm. Considerable similarity and specific features of fauna of parasites of S. mentella from the southeastern slope of Greenland and the pelagial of the Irminger Sea indicate the belonging of fish aggregations in these areas to a single intraspecies group and the migration of maturing specimens from the slope to the pelagial. A conclusion is made that the aggregations of S. mentella in the pelagial of the Irminger and Labrador seas represent a pelagic ecological group formed by rapidly maturing specimens; a near-bottom ecological group at deepwater sites of the slope of Greenland is formed by slowly maturing specimens. No mass migration of the redfish from deepwater areas to shallow sites of the slope and to the oceanic pelagial of the northern Atlantic was recorded.     

Correlation-regression analysis of parameters of auditory potentials

Characteristics (amplitude, latent period) of two types of evoked potentials arising in response to acoustic stimulation, namely the action potential of the auditory nerve and sonomotor evoked potential derived from skin of the postauricular region and back, were studied in guinea pigs. Correlation-regression analysis revealed the degree and type of association between the parameters of these potentials. For action potentials and sonomotor potentials (irrespective of from where the latter were recorded) close correlation was found (r = 0.93). Similar close correlation (r = 0.91) also was found when latent periods of the action potential and sonomotor evoked potentials recorded from skin of the postauricular region, but not from skin of the back, were compared. As a result of mathematical modeling data were obtained for pathogenetically based correction of disturbed functions of the auditory system.A. I. Kolomiichenko Kiev Research Institute of Otolaryngology, Ministry of Health of the Ukrainian SSR. Translated from Neirofiziologiya, Vol. 14, No. 3, pp. 254–259, May–June, 1982.     

Investigation of electrical responses recorded from the fenestra cochleae in cats

Electrical responses of the fenestra cochleae to stimulation by clicks of different intensity, polarity, and frequency, were studied in anesthetized cats. The absolute values of amplitude and latent period of the neural component of the response reflect the physiological state of the auditory nerve. Besides ordinary potentials characterized by peaks N1 and N2, specific responses were observed when clicks with an intensity of 85 dB or "rarefaction" clicks were used. Dependence of the amplitude of these responses on the intensity of acoustic stimuli of different polarity was investigated during a change in the rhythm of the stimulation; the effect of different rhythms of stimulation on the gradient of the curve reflecting this relationship was examined. The possible mechanisms of the effect of stimulus frequency are discussed.Scientific-Research Institute of Otolaryngology, Ministry of Health of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 11, No. 2, pp. 151–157, March–April, 1979.     

Effectiveness of seasonal malaria chemoprevention in three regions of Togo: a population-based longitudinal study from 2013 to 2020

Human landing catches (HLC) are an entomological collection technique in which humans are used as attractants to capture medically relevant host-seeking mosquitoes. The use of this method has been a topic of extensive debate for decades mainly due to ethical concerns. Many alternatives to HLC have been proposed; however, no quantitative review and meta-analysis comparing HLC to outdoor alternative trapping methods has been conducted. A total of 58 comparisons across 12 countries were identified. We conducted a meta-analysis comparing the standardized mean difference of Anopheles captured by HLC and alternative traps. To explain heterogeneity, three moderators were chosen for analysis: trap type, location of study, and species captured. A meta-regression was fit to understand how the linear combination of moderators helped in explaining heterogeneity. The possibility of biased results due to publication bias was also explored. Random-effects meta-analysis showed no statistically significant difference in the mean difference of Anopheles collected. Moderator analysis was conducted to determine the effects of trap type, geographical location of study, and the species of Anopheles captured. On average, tent-based traps captured significantly more Anopheles than outdoor HLC (95% CI: [− .9065, − 0.0544]), alternative traps in Africa captured on average more mosquitoes than outdoor HLC (95% CI: [− 2.8750, − 0.0294]), and alternative traps overall captured significantly more Anopheles gambiae s.l. than outdoor HLC (95% CI: [− 4.4613, − 0.2473]) on average. Meta-regression showed that up to 55.77% of the total heterogeneity found can be explained by a linear combination of the three moderators and the interaction between trap type and species. Subset analysis on An. gambiae s.l. showed that light traps specifically captured on average more of this species than HLC (95% CI: [− 18.3751, − 1.0629]). Publication bias likely exists. With 59.65% of studies reporting p-values less than 0.025, we believe there is an over representation in the literature of results indicating that alternative traps are superior to outdoor HLC. Currently, there is no consensus on a single “magic bullet” alternative to outdoor HLC. The diversity of many alternative trap comparisons restricts potential metrics for comparisons to outdoor HLC. Further standardization and specific question-driven trap evaluations that consider target vector species and the vector control landscape are needed to allow for robust meta-analyses with less heterogeneity and to develop data-driven decision-making tools for malaria vector surveillance and control.