Changes In Blood Glucose Concentration Research Articles

Magnesium from Deep Seawater as a Potentially Effective Natural Product against Insulin Resistance: A Randomized Trial.

Background and Objectives: Deep seawater has been shown to restore pancreatic function in obese diabetic mice and considerably improve the homeostatic model assessment for insulin resistance, total cholesterol, and low-density lipoprotein cholesterol concentrations in patients with impaired fasting glucose or glucose tolerance. In this study, the effect of 12-week daily consumption of magnesium (Mg2+)-containing deep seawater mineral extracts on blood glucose concentration and insulin metabolism-associated indicators was investigated in patients with impaired glucose tolerance. Materials and methods: In this 12-week randomized, double-blind trial, patients (n = 37) with impaired glucose tolerance consumed deep seawater mineral extracts. Changes in blood glucose concentration and related indicators were compared between the treatment group and placebo group (n = 38). Results: The fasting insulin, C-peptide, homeostatic model assessment for insulin resistance, quantitative insulin sensitivity check index, homeostatic model assessment of beta-cell function, and Stumvoll insulin sensitivity index values in the deep seawater mineral extract group showed improvements compared with the placebo group. However, no significant differences between groups were observed in fasting blood glucose, postprandial blood glucose, glycated hemoglobin, or incremental area under the curve values. Conclusions: Oral supplementation with deep seawater mineral extracts enriched in Mg2+ markedly improves insulin sensitivity in patients with pre-diabetes. This study illustrates the potential clinical application of natural Mg2+ from deep seawater to alleviate insulin resistance in patients with pre-diabetes. Trial registration: This trial was retrospectively registered with Clinical Research information Service (CRIS), No. KCT0008695, on 8 August 2023.

Frequency tunable non-invasive microwave blood glucose sensor based on negative impedance circuit

Abstract This article proposes a frequency adjustable non-invasive blood glucose microwave sensor based on negative impedance circuit. Firstly, this article establishes a skin-blood-skin human tissue model for the detection of non-invasive microwave sensors. Compared to traditional passive microwave blood glucose sensors, this design uses a negative impedance compensation circuit (NIC), greatly increasing microwave penetration and improving its detection sensitivity. In addition, this design achieves the goal of adjustable operating frequency by adding an additional dielectric layer at the detection end. This function is of great significance for microwave non-invasive blood glucose sensors. On the one hand, it can adjust to the optimal operating frequency band according to the characteristics of blood glucose changes; On the other hand, it is possible to measure changes in blood glucose concentration at multiple frequency points, thereby increasing the accuracy of detection. The relevant results show that adjusting the frequency band can reach 1–4 GHz, and the specific method of frequency adjustment is provided in the article; Meanwhile, four initial frequency points were selected in the article, at which the results show that the sensitivity reaches 1.356 × 10−3, 3.142 × 10−3, 2.071 × 10−3, 1.903 × 10−3. The above results demonstrate the superiority of our design, and blood glucose sensors based on this principle are expected to break through the limitations of current blood glucose sensors.

Effect of Neck-Deep Immersion in Cool or Thermoneutral Water on Blood Glucose Levels in Individuals With Type 1 Diabetes.

It is unclear whether immersion in cool water, typical of many beaches, increases the concentration of blood glucose in individuals with type 1 diabetes mellitus (T1DM). To test the hypothesis in individuals with T1DM that immersion neck-deep in cool water (COOL) causes an increase in blood glucose concentration, but not exposure to thermoneutral water (THERMO) or thermoneutral air. Eight overnight-fasted participants with T1DM were exposed for 60 minutes on separate days to 3 experimental conditions: cool water (COOL, 23 °C); thermoneutral water (THERMO, 33.5 °C); or thermoneutral air (24 °C). They then recovered for 60 minutes on land at 24 °C. At time intervals, we measured: blood glucose and plasma insulin concentration, rate of carbohydrate and fat oxidation, skin and core temperature, subcutaneous blood flow, and shivering via electromyography. There was no change in blood glucose concentration during the 3 experimental conditions (P > .05). During recovery after COOL, blood glucose increased (P < .05) but did not change in the other 2 conditions. The rate of carbohydrate oxidation during and early after COOL was higher than in the other 2 conditions (P < .05), and COOL led to a decrease in subcutaneous blood flow and the concentration of plasma insulin (P < .05). Cool or thermoneutral neck-deep immersion in water does not cause a change in the concentration of blood glucose in people with T1DM, but on-land recovery from COOL causes an increase in blood glucose that may be due, at least in part, to the accompanying decrease in plasma insulin.

Diagnosis of equine endocrinopathies: The value of measuring blood glucose during an oral glucose test

Blood glucose concentration is often measured during an oral glucose test (OGT), but is not thought to aid in diagnosing insulin dysregulation (ID) or pituitary pars intermedia dysfunction (PPID). The aim of this retrospective study was to investigate whether the change in blood glucose concentration during an OGT aligned with indicators of equine metabolic syndrome or PPID, including serum insulin and plasma ACTH concentrations, clinical observations, age, sex, breed type and the test dose. The cohort included 149 horses, miniature horses, and ponies that had undergone an in-feed OGT and clinical examination between 2015 and 2021. The animals were diagnosed as either metabolically healthy, insulin-dysregulated, having PPID or both endocrinopathies. The mean ± standard error increase in blood glucose during the OGT was 3.41 ± 0.21 mM, and this change showed a weak positive correlation with the increase in serum insulin concentration (r = 0.36; P 0.001), body condition score (BCS; r = 0.26; P = 0.002) and cresty neck score (CNS; r = 0.38; P 0.001). The median [interquartile range] increase in blood glucose for miniature horses (5.25 [2.98–6.5] mM), was more than twice that seen in full-sized horses (2.4 [1.33–3.45] mM; P = 0.03). In metabolically healthy animals the increase in blood glucose during an OGT (+2.2 [1–3.5] mM) was smaller (P 0.001) than in animals with ID (+3.8 [2.73–5.33] mM), or both endocrine diseases (+6.1 [3.6–6.85] mM). There was an effect of the dose of dextrose on the blood glucose response, with higher doses yielding larger responses (P 0.001). The variability in these data support that basal and post-prandial blood glucose responses to an OGT are not appropriate as stand-alone diagnostic markers of ID or PPID. However, the association between blood glucose and CNS supports the use of CNS when evaluating animals for ID.

Role of prior feeding status in mediating the effects of exercise on blood glucose kinetics.

Changes in blood glucose concentrations are underpinned by blood glucose kinetics (endogenous and exogenous glucose appearance rates and glucose disappearance rates). Exercise potently alters blood glucose kinetics and can thereby be used as a tool to control blood glucose concentration. However, most studies of exercise-induced changes in glucose kinetics are conducted in a fasted state, and therefore less is known about the effects of exercise on glucose kinetics when exercise is conducted in a postprandial state. Emerging evidence suggests that food intake prior to exercise can increase postprandial blood glucose flux compared with when meals are consumed after exercise, whereby both glucose appearance rates and disappearance rates are increased. The mechanisms underlying the mediating effect of exercise conducted in the fed versus the fasted state are yet to be fully elucidated. Current evidence demonstrates that exercise in the postprandial state increased glucose appearance rates due to both increased exogenous and endogenous appearance and may be due to changes in splanchnic blood flow, intestinal permeability, and/or hepatic glucose extraction. On the other hand, increased glucose disappearance rates after exercise in the fed state have been shown to be associated with increased intramuscular AMPK signaling via a mismatch between carbohydrate utilization and delivery. Due to differences in blood glucose kinetics and other physiological differences, studies conducted in the fasted state cannot be immediately translated to the fed state. Therefore, conducting studies in the fed state could improve the external validity of data pertaining to glucose kinetics and intramuscular signaling in response to nutrition and exercise.

Adaptive bolus calculators for people with type 1 diabetes: A systematic review.

To conduct a systematic review of studies assessing adaptive insulin bolus calculators for people with type 1 diabetes (T1D). Electronic databases (Medline, Embase and Web of Science) were systematically searched from date of inception to 13 October 2022 for single-arm or randomized controlled studies assessing adaptive bolus calculators only, in children or adults with T1D on multiple daily injections or insulin pumps with glycaemic outcomes reported. The Clinicaltrials.gov registry was searched for recently completed studies evaluating decision support in T1D. The quality of extracted studies was assessed using the Standard Quality Assessment criteria and the Cochrane Risk of Bias assessment tool. Six studies were identified. Extracted data were synthesized in a descriptive review because of heterogeneity. All the studies were small feasibility studies or were not suitably powered, and all were deemed to be at a high risk of performance and detection bias because they were unblinded. Overall, these studies did not show a significant glycaemic improvement. Two studies showed a reduction in postprandial time below range or an incremental change in blood glucose concentration; however, these were in controlled environments over a short duration. There are limited clinical trials evaluating adaptive bolus calculators. Although results from small trials or in-silico data are promising, further studies are required to support personalized and adaptive management of T1D.

Calving prediction with continuous measurement of subcutaneous tissue glucose concentration in pregnant cows.

To reduce losses of dams and calves due to unfortunate events, such as dystocia and freezing to death, identifying the onset of calving and providing necessary assistance are crucial. Prepartum increase in blood glucose concentration is a known indicator to detect labor in pregnant cows. However, some issues, including the need for frequent blood sampling and stress on cows, must be resolved before establishing a method for anticipating calving using changes in blood glucose concentrations. Herein, instead of measuring the blood glucose concentrations, subcutaneous tissue glucose concentration (tGLU) was measured in peripartum primiparous (n=6) and multiparous (n=8) cows at 15min intervals using a wearable sensor. A transient increase in tGLU was observed in the peripartum period, with peak individual concentrations occurring between 2.8h before and 3.5h after calving. tGLU in primiparous cows was significantly higher than that in multiparous cows. To account for individual variations in basal tGLU, the maximum relative increase in the 3-h moving average of tGLU (Max MA) was used to predict calving. Cutoff points for Max MA were established by parity, with receiver operating characteristic analysis predicting calving within 24, 18, 12, and 6h. Except for one multiparous cow that showed an increase in tGLU just before calving, all cows reached at least two cutoff points and calving was predicted successfully. The time interval between reaching the tGLU cutoff points that predicted calving within 12h and actual calving was 12.3±5.6h. In conclusion, this study demonstrated the potential role of tGLU as a predictive indicator of calving in cows. Advancements in machine learning-based prediction algorithms and bovine-optimized sensors will help in increasing the accuracy of calving prediction using tGLU.

Possible renoprotective mechanisms of SGLT2 inhibitors.

Treatment with a sodium glucose cotransporter 2 (SGLT2) inhibitor in patients with chronic kidney disease reduces the renal risk independent of changes in blood glucose concentrations and blood pressure. However, the precise mechanism responsible for this SGLT2 inhibitor-induced renoprotective effect is unclear. We have previously shown that SGLT2 inhibitors induce antihypertensive effects with decreased sympathetic nerve activity, which is associated with transient natriuresis. Furthermore, treatment with an SGLT2 inhibitor improves renal ischemia by producing vascular endothelial growth factor-a in the renal tubules. Other studies have suggested that ketone body production, changes in glomerular hemodynamics, and intrarenal metabolic changes and a reduction in oxidative stress due to decreased tubulointerstitial glucose levels may also be involved in the renoprotective effects of SGLT2 inhibitors. In this review, we summarize the mechanism responsible for the SGLT2 inhibitor-induced renoprotective effects, including our recent hypothesis regarding an "aestivation-like response," which is a biological defense response to starvation.

Effect of acute and chronic administration of Persia americana (chloroform extract of stem bark) on blood glucose concentration of normoglycaemic and streptozotocin-induced hyperglycaemic mice

The effect of acute and chronic administration of the chloroform extract of the stem bark of P. americana on the blood glucose concentration (BGC) of normoglycaemic and streptozotocin (STZ)-induced hyperglycaemic mice was investigated. Firstly, fifteen (15) young albino mice allocated into three groups of five animals each after a 12 hour overnight fast were treated as follows: group 1 – equi-volume of distilled water, group 11- a single acute dose of 1200 mg/kg IP chloroform extract of P. americana (equivalent to 75% of LD50) and group 111 – 20 mg/kg IP tolbutamide. Immediately after treatment, BGC was measured at 0, ½, 1, 2, 4, and 8 hrs. Secondly another population of 15 animals were shared into 3 groups of 5 animals each. Animals in group 1 were administered equi-volume of distilled water daily, group 11 and group 111 400 mg/kg IP (equivalent to 25% of LD50) extract of P. americana and 10 mg/kg IP of tolbutamide respectively daily for twenty- five days. BGC was measured on days 1, 5, 10, 15,20, 25. Changes in BGC of normoglycaemic and STZ-induced hyperglycaemic mice as a result of acute and chronic administration of extract was compared with values for tolbutamide (positive control) and distilled water (negative control). Results show that in normoglycaemic mice unlike the acute dose of 20 mg/kg IP reference drug tolbutamide, an acute dose of the extract (1200 mg/kg IP) did not significantly lower BGC. In the STZ-induced hyperglycaemic mice however, both the extract and the reference drug tolbutamide significantly lowered the BGC. With chronic administration both the extract and the reference drug significantly lower BGC in STZ-induced hyperglycaemic mice. It can be concluded therefore that acute and chronic administration of the chloroform extract of P. americana does have a hypoglycaemic activity only in STZ-induced hyperglycaemic mice. This may support the use of the stem bark of P. americana in the treatment of Diabetes mellitus.

Comparison of Glucose Administration Routes to Determine Glucose Tolerance in Old and Young Mice

Background: It has been observed that old mice have a better tolerance to glucose than young after an intraperitoneal injection of glucose. We hypothesized that an intraperitoneal injection of glucose overestimates glucose tolerance in old mice.&#x0D; Methods: We assessed differences in glucose tolerance outcomes in 2- (young, n=23) and 23- to 27-month-old (old, n=23) male C57BL/6J mice after an intraperitoneal (IP) or intravenous (IV) injection, or oral gavage (OG) of glucose.&#x0D; Results: The area under the curve (AUC) of the changes of blood glucose concentration over 2 hours after glucose administration was lower in old than young animals (p&lt;0.001). The AUC was higher after IV than either IP or OG (p&lt;0.001). However, normalized to peak glucose concentration, the time course was similar in young and old animals, and was – except for an earlier peak in IV than OG (p=0.013) – independent of route of administration.&#x0D; Conclusion: We suggest that 1) to determine glucose tolerance the time course of changes in glucose concentration rather than the AUC, which is significantly affected by excursion magnitude, is preferable; 2) glucose tolerance can be measured equally well with IP, IV and OG; 3) there is no significant age-related difference in glucose tolerance in mice.&#x0D; Keywords: glucose tolerance test, glucose uptake, aging, glucose intolerance, mice, diabetes.

Syngeneically transplanted insulin producing cells differentiated from adipose derived stem cells undergo delayed damage by autoimmune responses in NOD mice

Insulin-producing cells (IPCs) generated by our established protocol have reached the non-clinical ‘proof of concept’ stage. Our strategy for their clinical application is the autotransplantation of IPCs into patients with type 1 diabetes mellitus (T1DM). In this context, the autoimmunity that characterized T1DM is important, rather than allorejection. We aimed to determine how these IPCs respond to T1DM autoimmunity. IPCs were generated from the subcutaneous fat tissue of non-obese diabetic (NOD) mice using our protocol. IPCs derived from NOD mice were transplanted under the kidney capsules of NOD mice at the onset of diabetes and the subsequent changes in blood glucose concentration were characterized. Blood glucose decreased within 30 days of transplantation, but increased again after 40–60 days in three of four recipient NOD mice. In tissue samples, the numbers of CD4+ and CD8+ T cells were significantly higher 60 days after transplantation than 30 days after transplantation. In conclusion, IPCs significantly ameliorate the diabetes of mice in the short term, but are damaged by autoimmunity in the longer term, as evidenced by local T cells accumulation. This study provides new insights into potential stem cell therapies for T1DM.

An anticoagulant/hemostatic indwelling needle for oral glucose tolerance test

Indwelling needles are widely used in the clinic for their advantages of reducing the pain and discomfort caused by repeated venipuncture. Achieving anticoagulation and hemostasis with one single indwelling needle is highly desired from perspective of implantation patency and the prevention of needle-withdrawal-induced uncontrolled bleeding. Herein, we develop a sophisticated indwelling needle with an anticoagulant/hemostatic dual function by anchoring an anticoagulant heparin coating and a hemostatic hydrogel coating on the inner surface and the outer surface of the indwelling needle, respectively. The results of in vitro tests and continuous blood collections from the rabbit ear vein indicate that the anticoagulant coating can resist the adhesion of proteins and blood cells, and its anticoagulant effect can maintain the patency of the indwelling needle for 3 hours after implantation. Meanwhile, the xerogel-hydrogel transition of the hemostatic coating upon contacting blood promotes the aggregation of blood cells, thus sealing the puncture site to achieve complete hemostasis after needle removal. Importantly, this anticoagulant/hemostatic indwelling needle can replace traditional repeated puncture, and can be used to monitor blood glucose concentration changes in diabetic rats through continuous blood collection, portending its promising application in the oral glucose tolerance test.

Human body model with blood flow properties for non-invasive blood glucose measurement

In this paper, the authors propose a human body model with the final goal of developing non-invasive blood glucose measurement. Most wearable devices today include antennas and signal processing circuitry capable of non-invasive measurements. Authors plan to extend this circuitry for non-invasive blood glucose measurement with microwave technique. An optimum design of a proposed system needs a human body model. The authors have studied and compared various proposed methods in the published literature for non-invasive blood glucose measurement. Comparative study has concluded that the published human body models have dielectric-based tissue modelling and it is difficult to change the blood glucose concentration in it. Hence, a new human body model is derived and implemented in this work. The proposed model has provision to imitate the human blood flow and can vary blood glucose concentration for simulation purposes. Its accuracy has been defined and the proposed model was compared with standard dataset. It is established in simulation that with changes in blood glucose concentration the dielectric constant, electrical conductivity and other electrical parameters of blood also vary. Based on this, the parameters of the antenna mounted on body are affected. An antenna is fabricated to compare the simulation results with the actual test. It is found that blood glucose variation on extreme ends of the glucose concentration has return loss variation in range of 4–6 dB, while in 170 mg/dL–450 mg/dL range the variation is in between 1 and 3 dB values.

Evaluation of glucose absorption rates following intracoelomic or subcutaneous administration in experimentally dehydrated inland bearded dragons (Pogona vitticeps).

To evaluate glucose absorption rates as an indirect measure of fluid absorption after SC or intracoelomic (ICe) administration of 2.5% dextrose solution to experimentally dehydrated inland bearded dragons (Pogona vitticeps). 9 adult bearded dragons. In a randomized, blinded, placebo-controlled, crossover design study, bearded dragons were experimentally dehydrated with a previously described protocol and then received 2.5% dextrose solution (a 1:1 mixture of 5% dextrose in isotonic multiple electrolytes solution; 20 mL/kg), SC or ICe, or a control treatment (the same electrolytes solution without added glucose; 20 mL/kg). Blood glucose (BG) concentrations were measured at predetermined times up to 24 hours after fluid administration. There was a ≥ 14-day washout period between treatments. Mean changes in BG concentration from baseline were compared among treatments. Administration of 2.5% dextrose solution by either route increased BG concentration with a significantly greater change in values within 5 minutes, compared with control treatment results. The mean change in BG concentration after ICe administration was significantly greater than that after SC administration 15 and 30 minutes after injection, with mean differences of -50 and -36 mg/dL, respectively, for the SC treatment. Within 1 hour after fluid administration, there was no significant difference in BG values between the 2 dextrose administration routes. Findings supported that fluid therapy by SC administration, which carries a lower risk of iatrogenic complications, can provide results similar to those achieved with ICe administration.

Effects of psychological, sensory, and metabolic energy prime manipulation on the acute endocrine stress response in fasted women

The stress response supports survival through energy mobilization. Paradoxically, a low blood glucose level dampens the endocrine stress response, and sugar consumption prior to stress restores it. Thus, energy availability may play a causal role in the endocrine stress response. Yet, it has never been tested whether sweet taste or expectations towards a drink content modulate the stress response. We investigated the potential role of sweetness, energy load and expectations towards energy load of a drink consumed prior to stress in restoring stress reactivity after fasting. N = 152 women (meanage=21.53, sdage=2.61) participated in the Trier Social Stress Test for groups in the morning after an overnight fast. Prior to stress induction, participants consumed a drink containing saccharose (sugar, n = 51), an equally sweet drink containing non-caloric sweetener (sweetener, n = 46), or water (n = 56). Additionally, participants in the sugar and sweetener group (n = 97) were informed whether or not their drink contained any calories (energy prime), which was deceptive in 50% of the cases. Eight salivary cortisol (−30, −20, −10, 0, +12, +25, +35, +45 min) and three blood glucose samples (−30, 0, +25 min) were assessed throughout the experiment. The effects of the experimental manipulations on cortisol trajectories were tested using multilevel mixed models. We found that compared with water, sugar and sweetener both significantly increased cortisol stress reactivity and with comparable intensity. However, our sensitivity analysis revealed a significant effect of sugar on cortisol trajectories compared to water and to sweetener. Drink-induced changes in blood glucose concentration were not associated with increases in cortisol. The energy prime did not affect the stress response. Overall, we could replicate the boosting effect of sugar consumption in a female sample after 8 h of fasting. The specific contribution of sweet taste and metabolic hormones to this boosting effect should be tested more rigorously in sex-balanced designs in the future.

Feasibility Evaluation of Metamaterial Microwave Sensors for Non-Invasive Blood Glucose Monitoring.

The use of microwave technology is currently under investigation for non-invasive estimation of glycemia in patients with diabetes. Due to their construction, metamaterial (MTM)-based sensors have the potential to provide higher sensitivity of the phase shift of the S21 parameter () to changes in glucose concentration compared to standard microstrip transmission line (MSTL)-based sensors. In this study, a MSTL sensor and three MTM sensors with 5, 7, and 9 MTM unit cells are exposed to liquid phantoms with different dielectric properties mimicking a change in blood glucose concentration from 0 to 14 mmol/L. Numerical models were created for the individual experiments, and the calculated S-parameters show good agreement with experimental results, expressed by the maximum relative error of 8.89% and 0.96% at a frequency of 1.99 GHz for MSTL and MTM sensor with nine unit cells, respectively. MTM sensors with an increasing number of cells show higher sensitivity of 0.62° per mmol/L and unit cell to blood glucose concentration as measured by changes in . In accordance with the numerical simulations, the MTM sensor with nine unit cells showed the highest sensitivity of the sensors proposed by us, with an average of 3.66° per mmol/L at a frequency of 1.99 GHz, compared to only 0.48° per mmol/L for the MSTL sensor. The multi-cell MTM sensor has the potential to proceed with evaluation of human blood samples.

An Electromagnetic Band Gap-Based Complementary Split Ring Resonator Loaded Patch Antenna for Glucose Level Measurement

This paper reports a novel antenna design using a complementary split-ring resonator loaded truncated patch along with electromagnetic band gap structure etching on the ground plane. It can be used for non-invasive measurement of glucose concentration in blood plasma. The size of antenna design is compact having volume ( $20\times 15\times 1.524$ ) mm3. It has a wide bandwidth of 5.2 GHz, which covers a range from 24.1 GHz to 29.3 GHz with a resonant frequency of 25.55 GHz. 3D model of the fingertip is loaded on the radiating patch which works as an RF sensor. Simulation results of reflection coefficient S11 (dB) shows a deviation in resonant frequency due to change in electrical properties of blood plasma such as dielectric constant and dielectric loss tangent. After proper calibration in laboratory, such type of changes can be utilized in the glucose concentration monitoring of diabetic patients non-invasively. In laboratory, the measurements of S11 (dB) and frequency shift with respect to different time periods are observed. The proposed antenna works as an RF sensor that is able to transmit in 5G range from 24.1 GHz to 29.3 GHz for glucose level monitoring in real-time access. The accuracy and sensitivity of the proposed antenna based RF sensor towards small variation in electrical properties of blood due to change in blood glucose concentration are also evaluated and they are found to be satisfactory.

Towards robust glucose chemical exchange saturation transfer imaging in humans at 3T: Arterial input function measurements and the effects of infusion time.

Dynamic glucose-enhanced (DGE) magnetic resonance imaging (MRI) has shown potential for tumor imaging using D-glucose as a biodegradable contrast agent. The DGE signal change is small at 3T (around 1%) and accurate detection is hampered by motion. The intravenous D-glucose injection is associated with transient side effects that can indirectly generate subject movements. In this study, the aim was to study DGE arterial input functions (AIFs) in healthy volunteers at 3T for different scanning protocols, as a step towards making the glucose chemical exchange saturation transfer (glucoCEST) protocol more robust. Two different infusion durations (1.5 and 4.0min) and saturation frequency offsets (1.2 and 2.0ppm) were used. The effect of subject motion on the DGE signal was studied by using motion estimates retrieved from standard retrospective motion correction to create pseudo-DGE maps, where the apparent DGE signal changes were entirely caused by motion. Furthermore, the DGE AIFs were compared with venous blood glucose levels. A significant difference (p = 0.03) between arterial baseline and postinfusion DGE signal was found after D-glucose infusion. The results indicate that the measured DGE AIF signal change depends on both motion and blood glucose concentration change, emphasizing the need for sufficient motion correction in glucoCEST imaging. Finally, we conclude that a longer infusion duration (e.g. 3-4 min) should preferably be used in glucoCEST experiments, because it can minimize the glucose infusion side effects without negatively affecting the DGE signal change.

Preemptive Midazolam Can Reduce the Glycemic Stress Response to Surgery for Type-2 Diabetics Undergoing Simple Eye Surgery

Abstract Background: Estimation of percentage of change of blood glucose concentration (BGC) at 30- and 60-min after single dose of intravenous midazolam injection and at end of surgery in relation to pre-injection concentration. Aim of Study: Estimation of percentage of changes of blood glucose concentration (BGC) at 30- and 60-min after intravenous injection of single dose of midazolam and at end of surgery in relation to pre-injection BGC. Patients and Methods: 100 type-2 diabetic patients with fasting BGC of ³200mg/dl, ASA grade II or III and assigned for cataract surgery were evaluated clinically and received midazolam injection in a dose of 0. 0 1-0. 1 mg/kg, up to a total dose of 2.5mg, over two minutes or until patient was sedated and achieved Ramsy score 2 or 3. BGC was estimated before midazolam injection and at 30-min, 60-min after injection and at end of surgery. Then, patients received peribulbar and subtenon local anesthetic infiltration was performed. Results: All surgeries were conducted uneventfully within a mean operative time of 62.6±8.8 min. BGC showed progres-sive increases during surgery reaching a maximum at 60-min after injection and declined at end of surgery, but with non-significant differences between the three estimations and the pre-injection levels. Median value of percentage of increase of BGC at 60-min was significantly higher in comparison to median values of other estimations, with significantly higher percentage of increase at end of surgery than at 30-min after injection. Conclusion: Preemptive administration of midazolam for diabetic patients could control the surgery-induced hypergly-cemic effect and thus could protect patients against postoper-ative hyperglycemic complications.

A Dynamic Model of Glioma Tumor Growth Based on Changes in Blood Glucose Concentration using Runge-Kutta Order 45

The aggressive nature of the glioma tumor and the low survival rate of glioma sufferers make it very difficult to cure glioma tumors. The use of biomarkers in the blood to detect early glioma tumors is necessary for the evaluation of special treatment in patients with these tumors. Because there is a relationship between blood glucose concentrations and glioma tumors. This also opens up opportunities for the early detection of glioma tumors using the dynamic model method. This study presents the model of coupled ordinary differential equations to describe glioma growth based on changes in blood glucose concentration. This dynamic model contains glioma-glucose-immune interaction. The Runge-Kutta Order 45 function that has been created gives similar results with the MATLAB ode solver (ode45, ode23s, and ode15s). The simulation results indicate that there is an inverse relationship between glioma tumor growth (active state not in a dormant state) and a decrease in blood glucose serum levels. Also, there is a relationship between glioma growth and the immune system, which is an important element in controlling glioma tumor growth.