FEATURES OF THE RESPONSE OF THE RESPIRATORY CENTER OF NEWBORN RATS THAT WERE EXPOSED TO PRENANTAL PASSIVE SMOKING TO HYPOXIA (IN VITRO)

2016 ◽  
Vol 1 (60) ◽  
pp. 23-27
Author(s):  
Зинченко ◽  
Evgeniy Zinchenko ◽  
Болычевский ◽  
Stanislav Bolychevsky ◽  
Мирошниченко ◽  
...  

It is expected that in neonates that underwent prenatal chronic effect of nicotine the identification of the reduction of intensiveness of respiratory response to hypoxic exposure may be the cause of sudden infant death. The effect of cigarette smoke may differ from the effect of nicotine. The study was performed on brain stem spinal cord preparations (BSS) in the brain of newborn rats (n=38) in vitro. In the experimental group (EG) the modeling of passive smoking was carried out by fumigation of cigarette smoke of rat females from the 1st to 20th day of gestation. Hypoxia was simulated by an artificial cerebrospinal fluid saturated with a gas mixture of 5% CO2 and 95% N2. Hypoxic depression of BSS respiratory rhythm of the control group (CG) occurred at the 5th minute; the restoration took place in 10 minutes at normoxia, at the same time there was an increase of the amplitude of the inspiratory discharges which did not return to baseline values (15 minutes). In preparations of CG at the 10th minute of hypoxia the duration of inspiratory discharges decreased and restored after 10 minutes at normoxia. The increase of the ratio of the power of low-frequency and medium-frequency oscillations was observed in the CG at the 15th minute of hypoxia with the restoration during 10 minutes. In the experimental group (EG) the increase of the duration of the respiratory cycle occurred at the 10th minute of hypoxia with the dynamics of recovery similar to that of CG. The increase of the amplitude of inspiratory discharges occurred at the 10th minute of hypoxia; a recovery period took 10 minutes. In the BSS of EG the reduction in the duration of the inspiratory discharges and the increase of the ratio of the power oscillations of low- and mid-range occurred at the 5th and 10th minutes of hypoxia and these parameters never returned to baseline values. Our data suggest that prenatal exposure to secondhand smoke has an effect on the mechanisms of central chemosensitivity in the offspring in the early postnatal period.

Author(s):  
S. E. Bolychevsky ◽  
E. A. Zinchenko ◽  
I. V. Miroshnichenko

Both active and passive smoking increases the risk of sudden death of the newborn. Researchers are actively studying the effect of chronic nicotine infusion, as one of the leading neurogenic factors of tobacco smoke on cholinergic mechanisms of respiratory control. In this paper, using a fumigation model of passive smoking, tested the assumption that second-hand smoke that is transferred in the prenatal period, changes the expression mediated by nicotinic receptors activating influence of the cholinergic system of the brain stem to the processes of the respiratory activity of the neural network generation. It is found that the fumigation of tobacco smoke pregnant rats decreases their progeny respiratory sensitivity to the action of a neural network and exogenous nicotine increases cholinergic part tonic effect mediated by nicotinic cholinergic receptors in the modulation of respiratory rhythm. The study uses data obtained from 40 brain stem-spinal cord preparations (BSP) of the newborn rats. The experimental group was 22, and the control group was 18 newborn rats. In the processing of neurograms, the duration of the cycle of respiratory activity, duration, and the amplitude of inspiratory discharges were measured. To describe the peaks of the respiratory discharge spectrum, the following parameters were used: the peak frequency and the peak power spectral density of the peak. Analysis of the statistical differences was made using Student’s t-test for mean values. Differences were considered significant at p<0.05. Our results confirm the presence for exogenous nicotine of powerful activating effect on the generation frequency, amplitude and duration of inspiratory discharges of the BSP of newborn rats in the control group. It is established that an increase in the amplitude of the inspiratory discharges is accompanied by an increase in the spectral power density in the mid-frequency range of their spectrograms. In the BSP of the brain of newborn rats with prenatal exposure to tobacco smoke, exogenous nicotine increased only the frequency of inspiratory discharge generation. The amplitude of the inspiratory discharges and the power of the mid-frequency oscillations under the influence of exogenous nicotine in the BSP of the experimental group was significantly reduced. Mecamylamine, a selective blocker of nAChR, added to the perfusate of the BSP of the control group, caused a significant increase in the amplitude and duration of the inspiratory discharges, without significantly changing the duration of the respiratory cycle. At the same time, in BSP of newborn rats subjected to prenatal exposure to tobacco smoke, nAChR blockade resulted in an increase in the duration of the respiratory cycle. Thus, our study showed that fumigation of pregnant rats with tobacco smoke reduces the sensitivity of the respiratory neural network to the action of exogenous nicotine in early postnatal period and increases the involvement of tonic cholinergic effect mediated by nicotinic cholinergic receptors in modulating the respiratory rhythm.


Author(s):  
S. E. Bolychevsky ◽  
E. A. Zinchenko ◽  
I. V. Miroshnichenko

In the prenatal period, neural networks undergo the most significant morphological changes and subsequent functional transformations. The influence of a combination of factors of passive tobacco smoking to the development of the central mechanisms of respiratory control in the prenatal period remains unexplored. The present study was devoted to the study of the prenatal effect of passive smoking factors on the functioning of the central mechanisms of respiratory control in newborn rat. The study was carried out on 107 isolated brain stem-spinal cord preparations of the brain of newborn white outbred rats in vitro. Passive smoking was modeled by fumigating experimental animals with cigarette smoke. To simulate the hypercapnic effect, the bulbospinal preparations were perfused for 10 minutes with a solution of artificial cerebrospinal fluid with a saturated gas mixture, consisting of 10 % CO2 and 90 % O2; to simulate hypoxic exposure, the preparations were irrigated with a solution of artificial cerebrospinal fluid with a saturated gas mixture for 20 minutes 5 % CO2 and 95 % N2. As a result of the study, it was found that in newborn rats that underwent prenatal passive smoking, there is a high frequency of generation of inspiratory discharges, a shift in the spectral power density peaks of respiratory discharges in both ranges towards low frequencies, a decrease in their power, a decrease in the amplitude and a shorter duration of inspiratory discharges. in comparison with intact animals. A feature of the reaction to hypoxia in newborn rats who have undergone prenatal passive smoking is a late formation of the hypoxic depression of respiratory rhythm, reaction to hypercapnia characterized by no reduction in duration respiratory cycle. Thus performed by us research shows that prenatal secondhand smoke affects the mechanism of formation of the respiratory rhythm and pattern and also modifies the respiratory response to change in the partial tension of respiratory gases in cerebrospinal fluid in vitro.


2020 ◽  
pp. 194589242096761
Author(s):  
Osman Kılıç ◽  
Aslı Şahin Yılmaz ◽  
Çağatay Oysu

Introduction The aim of this study is to investigate the effect of cigarette smoke on turbinate reactivity and mucociliary clearance (MCC) in passive smokers. Methods 60 adult patients (30 passive smokers and 30 healthy subjects as the control group) were recruited for this study. Following a questionnaire on passive smoke exposure, MCC measurement using the saccharin test was carried out to all participants. The baseline and after decongestant acoustic rhinometry values (MCA1, MCA2, VOL1, VOL2) were measured and the percentage changes between the two test values (ie; response to nasal decongestants = concha reactivity) were recorded. Results All 60 patients, including 37 women (61.7%) and 23 men (38.3%) were between 18–57 years of age . MCC’s average measurements were 11.13 minutes in the passive smokers group, 7.87 minutes in the control group, which was statistically significantly different (p < 0.05). There was a statistically significant difference between the passive smokers and control group for acoustic rhinometric measurement of the ratio of MCA2 and VOL2 values before and after decongestant application (p < 0.05). Discussion Passive smoking can damage the nasal mucosa at least as active smoking. The number of studies on this subject is limited. There are no studies in the literature showing the effect of cigarette smoke on the inferior turbinate mucosal response. In our study, the inferior turbinate decongestant capacity was found to be significantly decreased in the passive smokers compared to the control group. Conclusion As a result of cigarette exposure, the erectile function of the lower turbines may be impaired. The task of the ENT physicians is to warn the passive smokers in this regard.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Hui Hua ◽  
Jiawei Cheng ◽  
Wenbo Bu ◽  
Juan Liu ◽  
Weiwei Ma ◽  
...  

Aim. To determine whether 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) is effective in combating ultraviolet A- (UVA-) induced oxidative photodamage of hairless mice skin in vivo and human epidermal keratinocytes in vitro. Methods. In in vitro experiments, the human keratinocyte cell line (HaCaT cells) was divided into two groups: the experimental group was treated with ALA-PDT and the control group was left untreated. Then, the experimental group and the control group of cells were exposed to 10 J/m2 of UVA radiation. ROS, O2− species, and MMP were determined by fluorescence microscopy; p53, OGG1, and XPC were determined by Western blot analysis; apoptosis was determined by flow cytometry; and 8-oxo-dG was determined by immunofluorescence. Moreover, HaCaT cells were also treated with ALA-PDT. Then, SOD1 and SOD2 were examined by Western blot analysis. In in vivo experiments, the dorsal skin of hairless mice was treated with ALA-PDT or saline-PDT, and then, they were exposed to 20 J/m2 UVA light. The compound 8-oxo-dG was detected by immunofluorescence. Conclusion. In human epidermal keratinocytes and hairless mice skin, UVA-induced oxidative damage can be prevented effectively with ALA-PDT pretreatment.


2020 ◽  
Vol 76 (03) ◽  
pp. 6356-2020 ◽  
Author(s):  
KATARZYNA PONIEDZIAŁEK-KEMPNY ◽  
BARBARA GAJDA ◽  
IWONA RAJSKA ◽  
LECHOSŁAW GAJDA ◽  
ZDZISŁAW SMORĄG

The aim of the study was to examine the in vivo viability of in vitro-produced (IVP) porcine embryos obtained from oocytes matured with thymosin. The research material for this study consisted of immature pig oocytes obtained from ovaries after slaughter and ejaculated semen obtained from one boar. The immature oocytes were cultured in vitro until the metaphase II stage in a medium supplemented with thymosin (TMS). The presumptive zygotes obtained were cultured in vitro for 4-40 hours. The presumptive zygotes and 2-4-cell embryos were evaluated in vivo after transferring them to synchronized recipients. After the transfer of embryos from the experimental group into 2 recipients (50 embryos into each gilt) and the transfer of 50 embryos from the control group into 1 recipient, both gilts that had received embryos obtained by in vitro fertilization of oocytes matured with TMS became pregnant and delivered a total of 16 live piglets. After the transfer of embryos from the control group, no pregnancy was achieved. In conclusion, the results of our preliminary study suggest that the maturation of pig oocytes with thymosin supports the in vivo survival of in vitro produced embryos. It is important to note, that this was the first birth of piglets obtained after transfer of IVP embryos in Poland.


2005 ◽  
Vol 17 (2) ◽  
pp. 190
Author(s):  
W.C. Chang ◽  
J. Xu ◽  
S. Jiang ◽  
X.C. Tian ◽  
X. Yang ◽  
...  

The aim of this experiment was to determine the effect of the sucrose concentration (0 to 0.33 M) in the dilution medium on the viability, fertilizability, and development of vitrified bovine oocytes. Bovine oocyte-cumulus complexes were collected from slaughterhouse ovaries and in vitro-matured as reported previously. After 24-h maturation in TCM199-based medium under 5% CO2 humidified air at 39°C, these were exposed to hyaluronidase and carefully pipetted to remove all except the 3–5 innermost layers of cumulus. Oocytes were put into the pre-equilibration medium for 3 min and then into vitrification solution containing HEPES-buffered TCM199 supplemented with 20% FBS, ethylene glycol, and dimethylsulphoxide for 25–30 s; they were then vitrified by modified solid surface vitrification (Dinnyes et al. 2000 Biol. Reprod. 63, 513–518).The oocytes were warmed at 39°C by placing them in holding medium with 0, 0.08, 0.17, 0.25, or 0.33 M sucrose. Non-vitrified oocytes were used as controls. Oocytes were inseminated 30 min after warming, and the presumptive zygotes were cultured in CR1-aa medium supplemented with 6 mg/mL BSA at 39°C in a humidified atmosphere of 5% CO2, 5% O2, and 90% N2 for eight days. Data were analyzed by one-way ANOVA. As shown in Table 1, there was no significant difference in survival rate (P > 0.05) of the vitrified oocytes that were placed in dilution solution containing 0.17, 0.25, or 0.33 M sucrose and the non-treated controls. On Day 2 (fertilized on Day 0), cleavage to the 8-cell stage was similar for the 0.17, 0.25, and 0.33 M dilution groups, but the rates for all three were significantly lower (P < 0.05) than for the control group. The blastocyst rate on Day 8 was significantly higher for the 0.25 M group than for any other experimental group but still significantly lower than for the control. In conclusion, this study suggests that with this vitrification/warming procedure the optimum concentration of sucrose in the dilution solution is 0.25 M. Table 1. Oocyte survival after vitrification/warming and subsequent embryo development The authors would like to thank Ms Colleen Shaffer for the preparation of bovine oocytes.


1998 ◽  
Vol 84 (6) ◽  
pp. 1991-1999 ◽  
Author(s):  
Hans G. Bone ◽  
Paul J. Schenarts ◽  
Stefanie R. Fischer ◽  
Roy McGuire ◽  
Lillian D. Traber ◽  
...  

We investigated the effects of modified hemoglobin on regional blood flow and function of different organs during hyperdynamic sepsis. Fourteen sheep were surgically prepared for the study. After a 5-day recovery period, a continuous infusion of live Pseudomonas aeruginosa bacteria was begun and maintained for 48 h. At 24 h, after a hyperdynamic circulation had developed, the animals were randomly assigned to two groups: 1) a treatment group ( n = 7) that received an infusion with 100 mg/kg pyridoxalated hemoglobin polyoxyethylene conjugate (PHP) over 30 min and 2) a control group ( n = 7) that received only the vehicle. PHP infusion increased mean arterial pressure from 86 ± 2.8 to 101.8 ± 3.5 mmHg ( P < 0.05) and systemic vascular resistance index from 769 ± 42.1 to 1,087 ± 56.8 dyn ⋅ s ⋅ m2⋅ cm−5( P < 0.05). PHP infusion did not decrease regional blood flow, measured with fluorescent microspheres, below the baseline values in any of the analyzed tissues. None of the investigated blood chemistry variables showed any changes indicative of impaired organ function after PHP infusion. In our model of ovine sepsis we found no side effects after PHP infusion that would limit the use of PHP as a nitric oxide scavenger in sepsis.


2016 ◽  
Vol 10 (03) ◽  
pp. 381-385 ◽  
Author(s):  
Jehona Ahmedi ◽  
Enis Ahmedi ◽  
Osman Sejfija ◽  
Zana Agani ◽  
Vjosa Hamiti

ABSTRACT Objective: The objective of this study was to assess the efficacy of ozone gas (O3) on the reduction of dry socket (DS) occurrence following surgical extraction of lower jaw third molars, influence of the indication for the extraction, and the difficulty of extraction on the incidence of DS. Materials and Methods: This study included thirty patients with bilaterally impacted third molars of mandible requiring surgical procedure for extraction. Following extraction, in the control group, saline solution was used for irrigation of extraction sockets and in the experimental group, intra-alveolar O3 was applied for 12 s (Prozone, W and H, UK, Ltd.). The surgeries were performed by the same oral surgeon. The follow-up visits were performed at 48 h and on day seven, postsurgery where the symptoms of DS were evaluated and intensity of pain has been recorded using visual analog scale 0–100. Results: In this pilot study, DS was present in 16.67% and 3.33% of cases in the control and experimental groups, respectively (P = 0.20). Conclusion: The application of O3 may reduce the incidence of DS and accelerates the recovery period after the surgery. Prophylactic use of O3 may be suggested in all patients, especially in the patients at a risk of development of DS.


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