scholarly journals Derangement of open-loop static and dynamic characteristics of the carotid sinus baroreflex in streptozotocin-induced type 1 diabetic rats

2018 ◽  
Vol 315 (3) ◽  
pp. R553-R567 ◽  
Author(s):  
Toru Kawada ◽  
Shuji Shimizu ◽  
Yohsuke Hayama ◽  
Hiromi Yamamoto ◽  
Keita Saku ◽  
...  
Keyword(s):  
Dynamic Characteristics ◽  
Carotid Sinus ◽  
Early Stage ◽  
Open Loop ◽  
Operating Point ◽  
Control Group ◽  
Static And Dynamic Characteristics ◽  
Carotid Sinus Baroreflex ◽  
Type 1 Dm

Although diabetes mellitus (DM) is a major risk factor for cardiovascular diseases, changes in open-loop static and dynamic characteristics of the arterial baroreflex in the early phase of DM remain to be clarified. We performed an open-loop systems analysis of the carotid sinus baroreflex in type 1 DM rats 4 to 5 wk after intraperitoneal streptozotocin injection ( n = 9) and we compared the results with control rats ( n = 9). The operating-point baroreflex gain was maintained in the DM rats compared with the control rats (2.07 ± 0.67 vs. 2.66 ± 0.22 mmHg/mmHg, P = 0.666). However, the range of arterial pressure (AP) control was narrower in the DM than in the control group (48.0 ± 5.0 vs. 77.1 ± 4.5 mmHg, P = 0.001), suggesting that the reserve for AP buffering is lost in DM. Although baroreflex dynamic characteristics were relatively preserved, coherences were lower in the DM than in the control group. The decreased coherence in the neural arc may be related to the narrowed quasi-linear range in the static relationship between carotid sinus pressure and sympathetic nerve activity in the DM group. Although the reason for the decreased coherences in the peripheral arc and the total reflex arc was inconclusive, the finding may indicate a loss of integrity of the baroreflex-mediated sympathetic AP control in the DM group. The derangement of the baroreflex dynamic characteristics is progressing occultly in this early stage of type 1 DM in a manner where dynamic gains are relatively preserved around the normal operating point.

Baroreceptor reflex cardiovascular control in mongrel dogs and racing greyhounds

1985 ◽  
Vol 249 (3) ◽  
pp. H655-H662 ◽  
Author(s):  
R. H. Cox ◽  
R. J. Bagshaw ◽  
D. K. Detweiler
Keyword(s):  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Carotid Sinus ◽  
Open Loop ◽  
Baroreceptor Reflex ◽  
Operating Point ◽  
Baroreflex Control ◽  
Pulsatile Pressure ◽  
Carotid Sinus Baroreflex ◽  
Before And After

The open-loop carotid sinus baroreflex control of arterial pressure-flow relations were compared in mongrel dogs and racing greyhounds (GH) anesthetized with alpha-chloralose. The carotid sinuses were bilaterally isolated and perfused under controlled pressure. Pulsatile pressure and flow were simultaneously measured in the ascending aorta, the celiac, superior mesenteric, left renal, and right iliac arteries. Open-loop set point values of mean arterial pressure were higher in GH before and after vagotomy. Reflex gains were similar before vagotomy but lower in GH after vagotomy. The overall range of control of arterial pressure was the same before vagotomy but smaller in GH after vagotomy. The variation of mean arterial pressure with mean carotid sinus pressure in GH was shifted toward higher pressure levels similar to resetting. The overall effects of vagotomy on carotid sinus baroreceptor reflex responses were smaller in GH. Operating point values of regional resistance were generally smaller in GH. Operating point sensitivities of regional resistance were the same except for the iliac bed, which was more sensitive in GH. These results document significant regional differences in the baroreceptor control of regional hemodynamics between mongrels and greyhounds that could contribute to altered responses especially to "hypertensive" perturbations.

scholarly journals Acute Effects of Vagotomy on Baroreflex Equilibrium Diagram in Rats with Chronic Heart Failure

2016 ◽  
Vol 10 ◽  
pp. CMC.S38443 ◽  
Author(s):  
Toru Kawada ◽  
Meihua Li ◽  
Can Zheng ◽  
Masaru Sugimachi
Keyword(s):  
Heart Failure ◽  
Carotid Sinus ◽  
Equilibrium Diagram ◽  
Open Loop ◽  
Operating Point ◽  
Arterial Baroreflex ◽  
Static Characteristics ◽  
Acute Effects ◽  
Vagal Modulation ◽  
Carotid Sinus Baroreflex

The arterial baroreflex system can be divided into the neural arc, from pressure input to efferent sympathetic nerve activity (SNA), and the peripheral arc, from SNA to arterial pressure (AP). Plotting the neural and peripheral arcs on a pressure–SNA plane yields a baroreflex equilibrium diagram. We examined the effects of vagotomy on the open-loop static characteristics of the carotid sinus baroreflex in normal control rats (NC, n = 10) and rats with heart failure after myocardial infarction (MI, n = 10). In the NC group, vagotomy shifted the neural arc toward higher SNA and decreased the slope of the peripheral arc. Consequently, the operating-point SNA increased without a significant change in the operating-point AP on the baroreflex equilibrium diagram. These vagotomy-induced effects were not observed in the MI group, suggesting a loss of vagal modulation of the carotid sinus baroreflex function in heart failure.

Autoimmune thyroid disease in patients with anti-GAD positive type 1 diabetes mellitus

Open Medicine ◽  
2009 ◽  
Vol 4 (4) ◽  
pp. 415-422
Author(s):  
Kamile Gul ◽  
Ihsan Ustun ◽  
Yusuf Aydin ◽  
Dilek Berker ◽  
Halil Erol ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Type 1 Diabetes ◽  
Type 1 Diabetes Mellitus ◽  
Statistical Significance ◽  
Control Group ◽  
Acid Decarboxylase ◽  
Thyroid Peroxidase ◽  
The Difference ◽  
Type 1 Dm

AbstractThe aim of the study was to determine the frequency and titers of anti-thyroid peroxidase (Anti-TPO), anti-thyroglobulin (Anti-TG), and anti-glutamic acid decarboxylase (Anti-GAD) antibodies in Turkish patients with type 1 diabetes mellitus (DM), and to compare the frequency of anti-TPO and anti-TG titers in the presence or absence of anti-GAD. A total of 104 patients including 56 males and 48 females with type 1 DM and their age-, gender-, and body mass index-matched control group, including 31 males and 27 females, 58 cases in total with an age range of 15-50 years, were recruited into this study. In patients with type 1 DM, positive anti-GAD was detected in 30.8% (n=32). In patients with positive anti-GAD, rate of positive anti-TPO was 37.5%; however, in patients with negative anti-GAD, the rate of positive anti-TPO was 9.7% and the difference was statistically significant (p=0.001). In patients with positive anti-GAD, the rate of positive anti-TG was 18.8%. In patients with negative anti-GAD, the rate of positive anti-TG was 2.8%, and the difference between them was statistically significant (p=0.005). In patients with positive and negative anti-GAD, rates of both positive anti-TPO and anti-TG were 15.6% and 1.4%, respectively, with the difference showing statistical significance (p=0.004). Thyroid autoimmunity in type 1 DM patients with positive anti-GAD was apparently higher; therefore, these patients should be followed more frequently and carefully.

scholarly journals Risk of Urticaria in Children with Type 1 Diabetes Mellitus: A Nationwide Cohort Study

2019 ◽  
Vol 17 (1) ◽  
pp. 176
Author(s):  
Shih-Yi Lin ◽  
Cheng-Li Lin ◽  
Cheng-Chieh Lin ◽  
Wu-Huei Hsu ◽  
Chung-Y. Hsu ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Type 1 Diabetes ◽  
Type 1 Diabetes Mellitus ◽  
Hazard Ratio ◽  
Control Group ◽  
Case Group ◽  
Research Database ◽  
Increased Risk ◽  
Type 1 Dm

Type 1 diabetes mellitus (T1DM) has been linked to many autoimmune problems. The association between T1DM and urticaria warrants investigation. Data were extracted from the National Health Insurance Research Database (NHIRD) of Taiwan. Participants with T1DM were recruited as the case group, and that group was matched by sex and age at a ratio of 1:4 to the control group comprising those without T1DM. The study period was 1998–2011. All participants were followed up to the diagnosis of urticaria, withdrawal from the insurance program, death, or the end of the study. A multivariable Cox proportional hazard model was used to calculate the adjusted and crude hazard ratios for urticaria. A total of 5895 participants (1179 in the case group and 4716 in the control group) were followed up in the study. The total incidence rate of urticaria in patients with type 1 DM was 26.6 per 1000 person-years, and that in controls was 6.85 per 1000 person-years. Compared with the control group, the hazard ratio of urticaria in the case group was 2.84 (95% CI = 2.27–3.56). Compared with age-matched participants without T1DM, patients with type 1 DM aged <18 years had a 3.62-fold higher risk of urticaria (95% CI = 2.85–4.59). The hazard ratio in patients with an adjusted Diabetes Complications Severity Index (aDCSI) score of 1.01–2.00 per year was 2.57 (95% CI = 1.18–5.57), and that in patients with an aDCSI score of >2.00 per year was 4.47 (95% CI = 2.68–7.47). T1DM patients aged <18 years had an increased risk of urticaria, but a similar phenomenon was not observed among T1DM patients older than 18 years.

Closed-loop identification of carotid sinus baroreflex open-loop transfer characteristics in rabbits

1997 ◽  
Vol 273 (2) ◽  
pp. H1024-H1031 ◽  
Author(s):  
T. Kawada ◽  
M. Sugimachi ◽  
T. Sato ◽  
H. Miyano ◽  
T. Shishido ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Closed Loop ◽  
Transfer Functions ◽  
Carotid Sinus ◽  
Open Loop ◽  
Parametric Models ◽  
Efferent Nerve ◽  
Transfer Characteristics ◽  
Carotid Sinus Baroreflex ◽  
Closed Loop Identification

In the circulatory system, a change in blood pressure operates through the baroreflex to alter sympathetic efferent nerve activity, which in turn affects blood pressure. Existence of this closed feedback loop makes it difficult to identify the baroreflex open-loop transfer characteristics by means of conventional frequency domain approaches. Although several investigators have demonstrated the advantages of the time domain approach using parametric models such as the autoregressive moving average model, specification of the model structure critically affects their results. Thus we investigated the applicability of a nonparametric closed-loop identification technique to the carotid sinus baroreflex system by using an exogenous perturbation according to a binary white-noise sequence. To validate the identification method, we compared the transfer functions estimated by the closed-loop identification with those estimated by open-loop identification. The transfer functions determined by the two identification methods did not differ statistically in their fitted parameters. We conclude that exogenous perturbation to the baroreflex system enables us to estimate the open-loop baroreflex transfer characteristics under closed-loop conditions.

Lack of time-dependent augmentation of carotid sinus baroreflex system after vagotomy

1982 ◽  
Vol 242 (4) ◽  
pp. H580-H584
Author(s):  
H. Hosomi ◽  
K. Yokoyama
Keyword(s):  
Control System ◽  
Arterial Pressure ◽  
Carotid Sinus ◽  
Pressure Control ◽  
Open Loop ◽  
Carotid Sinus Baroreflex ◽  
Stepwise Reduction ◽  
Intact Condition ◽  
Pressure Control System ◽  
Arterial Pressure Control System

The purpose of this experiment was to study whether the carotid sinus baroreflex system (CS system) increases its gain with time after vagotomy in compensation for the loss of the vagally mediated arterial pressure control system (V system). In 7 dogs anesthetized with pentobarbital sodium we determined the responsiveness of the V system by repeatedly measuring the overall open-loop gain (G) of the negative feedback control system. G was assessed as (delta API/delta APS) -- 1, where delta API and delta APS are, respectively, the immediate and steady-state falls in arterial pressure at the aortic arch following a stepwise reduction in blood volume. delta API, delta APS, and G in intact condition were -12.0 +/- 1.8 mmHg, -1.1 +/- 0.2 mmHg, and 10.1 +/- 0.7 (SD), respectively. delta API, delta APS, and G after vagotomy, i.e., G of the CS system (GCS), were -15.6 +/- 3.6 mmHg, -6.4 +/- 1.9 mmHg, and 1.6 +/- 0.4 GCS did not change with time over 4 h after vagotomy. We conclude that the CS system cannot augment its ability to restore arterial pressure in compensation for the lost function of the V system within 4 h after vagotomy in the anesthetized dog.

scholarly journals Relationship between TP53 and interleukin-6 gene variants and the risk of types 1 and 2 diabetes mellitus development in the Kermanshah province

2021 ◽  
Vol 14 (1) ◽  
pp. 37-44
Author(s):  
Lida Haghnazari ◽  
◽  
Ramin Sabzi ◽  
◽  
Keyword(s):  
Diabetes Mellitus ◽  
Tp53 Gene ◽  
Control Group ◽  
Control Groups ◽  
Codon 72 ◽  
Type 2 Dm ◽  
And Control ◽  
Type 1 Dm

Diabetes mellitus (DM) is a metabolic disorder that results from insufficient secretion or insulin resistance, or both. Insulin secretion deficiency leads to chronic hyperglycemia along with impaired metabolism of proteins, lipids, and carbohydrates. This study aimed to investigate the TP53 gene SNP (single nucleotide polymorphism) rs1042522 genotype and the interleukin-6 (IL-6) gene SNP rs1800795 genotype in DM and control groups. This study was performed on 70 patients with type 1 DM, 100 patients with type 2 DM without related complications, 66 control subjects for type 1 DM, and 95 control subjects for type 2 DM. The control groups were matched regarding age and gender and did not have a familial relationship with the patient groups. All the subjects were residents of Kermanshah, located in the western part of Iran. Polymorphisms of TP53 and IL-6 genes were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Lipid profile, fasting blood glucose, and HbA1c were measured using the ELISA and immunoturbidometric methods. The frequency of genotypes (CC, CG, GG) of the TP53 gene codon 72 in type 1 DM and its control group were significantly different (P= 0.013). Likewise, the frequency of genotypes (CC, CG, GG) of the TP53 gene codon 72 was significantly different between type 2 DM and control groups (P <0.001). The frequency of genotypes (GG, GC, CC) of G174C polymorphisms in the IL-6 gene was different between type 1 DM and control group as well as between type 2 DM and its control group, but it was not statistically significant. SNP rs1042522 genotypes in the dominant form (CG + GG vs. CC) (OR= 3.880; P < 0.001) and alleles G vs. C alleles (OR= 0.384; P < 0.001) increased the risk of type 2 DM significantly. There was no significant difference between type 1 and type 2 DM groups and respected control groups regarding the frequency of the IL-6 gene SNP rs1800795 alleles. The G allele of SNP rs1042522 encoding the TP53 gene increases the risk of developing DM in the population of the Kermanshah province, Iran.

scholarly journals Hand functions in type 1 and type 2 diabetes mellitus

2017 ◽  
Vol 145 (11-12) ◽  
pp. 584-588
Author(s):  
Pinar Akpinar ◽  
Afitap Icagasioglu ◽  
Esra Selimoglu ◽  
Banu Mesci
Keyword(s):  
Diabetes Mellitus ◽  
Grip Strength ◽  
Control Group ◽  
Hand Functions ◽  
Type 2 Dm ◽  
Significant Difference ◽  
Hand Disability ◽  
Type 1 Dm

Introduction/Objective. Hand functions have an enormous impact on activities of daily living in patients with diabetes mellitus (DM), such as self-care, administering insulin injections, and preparing and eating meals. The aim of the study was to evaluate hand functions and grip strength in patients with type 1 and type 2 DM. Methods. This was an observational case-control study investigating the hand functions and grip strength in patients with type 1 and type 2 DM. The study comprised 41 patients with type 1 DM aged 25?50 years sex- and age-matched, 40 non-diabetic controls, and 91 patients with type 2 DM aged 40?65 years sex- and age-matched 60 non-diabetic controls. Patients with documented history of diabetic sensorimotor neuropathy and adhesive capsulitis were excluded. The Duruoz Hand Index was used to assess the functional hand disability. Grip strength was tested with a calibrated Jamar dynamometer. Results. The Duruoz Hand Index scores in patients with type 2 DM were significantly higher than in persons in the control group (p < 0.01), but there was no significant difference between the type 1 DM and the control group (p > 0.05). Grip strength values of patients with type 1 DM were significantly lower compared to those in the control group (p < 0.05), whereas there was no significant difference between patients with type 2 DM and their control group. There was a negatively significant correlation between grip strength and the Duruoz Hand Index scores in patients with both type 1 and type 2 DM (p < 0.05). Conclusion. Patients with type 1 DM and type 2 DM have different degrees of hand disability as compared to healthy control groups.

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