Clinical and Functional Outcomes of Suture Versus Headless Screw Fixation for Tibial Eminence Fractures in Children

BACKGROUND

Suture and screw fixations are widely used to treat tibial eminence fractures (TEFs). Although a few biomechanical and clinical studies have compared suture fixation (SF) and screw fixation in the treatment of TEFs in children, no comparative clinical studies are available regarding headless screw fixation (HSF).

PURPOSE

To evaluate the clinical and functional outcomes of children with TEF who underwent SF and HSF.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The study included 24 patients treated with either SF (11 patients) or HSF (13 patients) within 1 month of TEF (type 2 or 3) without associated ligamentous and bone injury between 2015 and 2020. All patients were evaluated at a minimum 2-year follow-up in terms of Lysholm score, Tegner activity level, International Knee Documentation Committee subjective score, and isometric strength test. Knee stability was compared based on the Lachman test, pivot-shift test, and KT-1000 arthrometer side-to-side difference.

RESULTS

No significant differences were found between the 2 groups in terms of Lysholm score, Tegner activity level, and International Knee Documentation Committee subjective score at follow-up. All patients were able to resume their daily activities within 6 months after the injury. However, flexion deficits (6°-10°) were found in 2 patients in the SF group and 1 patient in the HSF group, and extension deficits (3°-5°) were found in 3 patients in the SF group and 1 patient in the HSF group, without significant intergroup difference. Stability based on the Lachman test, pivot-shift test, and KT-1000 arthrometer side-to-side difference was also similar between the 2 groups at follow-up. No statistically significant difference was found between the 2 groups in isometric tests performed.

CONCLUSION

The present study is the first to compare the clinical and functional results of SF and HSF techniques. The HSF technique demonstrated comparable clinical and functional outcomes, suggesting its potential as an alternative to the SF technique.

Biomechanical performance of talon cannulated compression device in pauwels type III fractures: a comparative study

INTRODUCTION

Pauwels Type III fractures are unstable and frequently treated with cannulated screws (CS) or dynamic hip screws (DHS). The newly developed talon-cannulated compression devices (TCCD) have the potential to provide rotational stability, mainly through their talon. The study investigates whether TCCD has mechanical advantages over conventional screws or can be as stable as DHS in a reverse triangle configuration for an unstable femoral neck fracture.

MATERIAL AND METHODS

After creating a standard Pauwels Type III unstable femoral neck fracture in 36 synthetic femur bones in cortical/hard cancellous bone density, 18 were reserved for dynamic-static tests, and 18 were used for torsional tests. Each group containing 18 synthetic bones was divided into three groups to apply three different fixation materials (CS, DHS, and TCCD), with six models in each group. The displacement amounts after dynamic-static tests were measured using the AutoCAD program according to the reference measurement criteria. During the dynamic tests, a series of photographs were taken. During the static tests, the beginning and post-test photographs were taken. Finally, torsional tests were performed until implant failure occurred in the synthetic femur.

RESULTS

In static axial loading tests, TCDD was found to be statistically superior to conventional CS in AL-BL distance (p = 0,014) and CL distance (p = 0,013) measurements, and there was no significant difference between the other groups. There was no significant difference between all groups in dynamic axial compression tests in any points of interest. In torsional tests, TCCD outperformed cannulated screws in stiffness (p = 0,001) and maximum torque (p = 0,001) categories, and they provided statistically significant superiority to DHS in yield torque (p<0,001) category.

CONCLUSIONS

Biomechanically, TCCD predominates conventional cannulated screws in femoral neck fractures. TCCD also has superior torsional properties than DHS in the yield torque category. Therefore, TCCD could be the implant of choice for unstable femoral neck fractures.

During Arthroscopic Repair of Medial Meniscal Tears: Do Not Be Afraid to Perform "Pie Crust" Technique

In the absence of effective long-term repair of meniscal injuries, damage to the knee may lead to the development of osteoarthritis. Recent reports have recommended meniscal repair to be undertaken in all cases of meniscal tears. However, the most common complication encountered during repair of the medial meniscus is iatrogenic cartilage and meniscal injury due to its unclear visualization. The aim of this study is to evaluate the long-term clinical and radiological results of the pie-crust (PC) technique performed during the repair of medial meniscal tears. This retrospective study included 86 patients who underwent arthroscopic medial meniscus repair. PC technique was performed if the medial joint width was less than 5 mm. The patient population was divided into two groups as who underwent meniscus repair with PC technique (PC + repair group) or not (repair group). All patients were evaluated clinically (Kujala score, International Knee Documentation Committee (IKDC) subjective score, Lysholm score, and Tegner activity score) and radiologically (medial joint width and valgus laxity angle). When the medial joint width measurements before the PC technique and at the postoperative first and sixth months were compared, it was found to be statistically significant (p < 0.05). However, there was no significant difference between the preoperative and 12-month postoperative joint width measurements (p > 0.05). At the 12-month follow-up, no statistically significant difference was determined for the valgus laxity angle in the PC group compared with preoperative values (p > 0.05). The follow-up Kujala score, IKDC subjective score, Lysholm score, and Tegner activity score were similar between the groups. The clinical scores in both groups were determined to have statistically significant increase at 12-month postoperatively compared with the preoperative values (p < 0.05). The results of this study showed that performing the PC technique prior to medial meniscal tear repair increase the medial joint visualization safely and effectively without permanent valgus laxity.

Risk factors for brachial plexus injury and permanent sequelae due to shoulder dystocia

AIM

The primary aim of this study was to determine the risk factors for the occurrence of brachial plexus injury in cases of shoulder dystocia. Secondly, it was aimed to determine the factors affecting the occurrence of permanent sequelae in cases with brachial plexus injury.

SUBJECTS AND METHODS

ICD-10 codes were scanned from the records of patients who gave birth between 2012 and 2018, and the records of patients with brachial plexus injury and shoulder dystocia were reached. Shoulder dystocia cases with brachial plexus damage were accepted as the study group, and shoulder dystocia cases without brachial plexus damage were considered the control group. Shoulder dystocia patients with brachial plexus injury and without injury were compared for 2-year orthopedics clinic follow-up reports, surgical intervention, permanent sequelae status as well as birth data, maternal characteristics, and maneuvers applied to the management of shoulder dystocia.

RESULTS

Five hundred sixty births with shoulder dystocia were detected. Brachial plexus injury was observed in 88 of them, and permanent sequelae were detected in 12 of these patients. Maneuvers other than McRobert's (advanced maneuvers) were used more and clavicle fracture was seen more in the group with plexus injury (P < 0.05, P < 0.05, respectively). Logistic regression analysis was performed to determine the risk factors of brachial plexus injury. Brachial plexus injury was observed 4.746 times more in infants who were delivered with advanced maneuvers and 3.58 times more in infants with clavicle fractures at birth.

CONCLUSION

In patients with shoulder dystocia, the risk of brachial plexus injury increased in deliveries in which advanced maneuvers were used and clavicle fracture occurred.

Which Fibers of the Medial Collateral Ligament (MCL) Should Be Released in the Pie Crust Technique Applied During Knee Arthroscopy: Superficial MCL or Deep MCL?

Background

Knee arthroscopy is the most common surgery performed to treat meniscal injuries. The pie crust (PC) technique is applied during knee arthroscopy to increase joint vision of the medial femorotibial compartment and reduce the risk of iatrogenic damage. Medial collateral ligament (MCL) release is applied in the PC technique. Currently, there are no studies directly comparing the release of the superficial MCL (sMCL) or deep MCL (dMCL) when applied during the PC technique. In this study, we compared the clinical and functional results of the release of the deep and proximal tibial attachment of the superficial fibers of the MCL.

Methodology

We evaluated the results of 67 (27 women and 40 men) patients who underwent the PC technique during knee arthroscopy due to a medial meniscal tear. The patients who underwent the PC technique were divided into two groups according to the release of the deep and superficial fibers of the MCL. All patients were evaluated for pain, functional capacity, and laxity using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Oxford Knee scores. All patients were evaluated with radiographic examinations such as valgus laxity angle and medial tibiofemoral compartment opening height.

Results

The KOOS and Oxford Knee Scores in both groups showed a statistically significant increase at 12 months postoperatively compared with the preoperative values (p = 0.005, 0.002, 0.002, and 0.01, respectively). No statistically significant difference was found between the groups (p > 0.05). When the valgus laxity angle before the PC technique was compared with the 12-month result after the procedure, no statistically significant difference was noted (p > 0.05). There was no evidence of complications such as chondral injury and saphenous nerve or vein injury among patients in either group.

Conclusions

In this study, we did not observe laxity in the long-term follow-up of the groups in which the superficial or deep fibers of the MCL were released. In our view, the PC technique has similar effects on surgical outcomes regardless of sMCL and dMCL release techniques.

Combined clinical test and magnetic resonance imaging have similar diagnostic values in the diagnosis of subscapularis tear

PURPOSE

The aim of the present study was to compare the diagnostic values of clinical tests and magnetic resonance imaging (MRI) which used for the diagnosis of subscapularis (SSc) tears in the patients who underwent arthroscopic rotator cuff surgery.

METHODS

Two-hundred and nine consecutive patients who underwent arthroscopic rotator cuff surgery between 2015 and 2019 were analyzed. The lift-off test, belly-press test and bear-hug test were performed preoperatively. 1.5 T MRI scans of all patients were evaluated for SSc integrity. The diagnostic values of both clinical tests and MRI were calculated. SSc tears were graded according to Fox and Romeo. Arthroscopic findings were used as the gold standard for diagnosis of SSc tears.

RESULTS

There were 54 SSc tears accounting for an prevalence of 29%. The BHT showed the greatest sensitivity for both type II-II-IV (73.3%) and all types of (68.5%) SSc tears. The sensitivity and specificity of the combined test and MRI were 91.1-87.2% and 93.3-90.8% in Type II-III-IV SSc tears, respectively, and 81.5-88.6% and 88.9-94.7% in all SSc tears, respectively. There were no statistically significant difference between combined test and MRI in terms of sensitivity and specificity (n.s.).

CONCLUSION

The present study is the first that compared both clinical tests and MRI with arthroscopic findings in terms of sensitivity and specificity in the same patient group. A combination of clinical tests increases their diagnostic values and shows similar sensitivity and specificity as MRI.

LEVEL OF EVIDENCE

I.

Steroid Injection and Biomarker Levels in the Treatment of Unicameral Bone Cysts: Can we Estimate the Result?

BACKGROUND

Steroid injection is a common method in the treatment of unicameral bone cysts (UBC). In this study, the relationship between the clinical results and inflammatory molecules' levels in the cyst fluid was evaluated after three repeated steroid injections in UBC subjects.

METHODS

Twenty-one patients diagnosed with UBC were treated with methylprednisolone acetate (MPA) injections. Patients were given three injections, each containing MPA, 6-8 weeks apart. Plain radiographs were obtained and cyst healing was evaluated according to modified Neer classification. Cyst fluid samples were taken. Samples were taken at first and last operations and were studied using the ELISA method to examine IL-1β, PGE2, MMP-1, and VEGF-A levels.

RESULTS

There were 17 and 4 cases localized to the humerus and femur, respectively. The mean follow-up period was 36.9 months. Complete recovery was achieved in 13 patients (61.9%) receiving MPA. Four patients (19%) recovered with residual lesions. One patient (4.7%) did not respond to steroid injections at all. In three patients (14.2%) the cyst recurred. Results were satisfactory in 17 patients (80.9%) and totally unsuccessful in 4 patients (19%). IL-1β, PGE2, and MMP-1 levels in cyst fluid were not affected by injection (p > 0.05), but VEGF-A levels decreased significantly with cyst healing (p = 0.01).

CONCLUSION

Steroid injection is a good choice in the treatment of UBC because of its less aggressive and relatively good outcome. It may be considered to evaluate the response to treatment by performing biomarker monitoring especially VEGF-A in repeated injections.

LEVEL OF EVIDENCE

Level II study.

Single-tunnel and double-tunnel medial patellofemoral ligament reconstructions have similar clinical, radiological and functional results

PURPOSE

The aim of the present study was to evaluate the clinical, radiological and functional results of patients underwent single-tunnel (ST) and double-tunnel (DT) medial patellofemoral ligament(MPFL) reconstructions with hamstring autograft following recurrent patella dislocation prospectively in a single institution.

METHODS

From 2013 to 2017, 80 patients with symptomatic recurrent patellar dislocation or instability were randomly divided into 2 groups for MPFL reconstruction with ST technique or DT technique and evaluated prospectively. In the ST group, there were 20 male and 20 female with a median follow-up of 46.5 months (range 24-74). The median age was 15 years (range 10-28). In the DT group, there were 18 male and 22 female with a median follow-up of 40 months (range 24-74). The median age was 19 years (range 14-29). Clinical scores (Kujala score, Lysholm score, Tegner score and IKDC score) and radiological measurements (congruence angle and patellar tilt angle) of the patients were evaluated preoperatively and at postoperative 24th month. Isokinetic dynamometric tests were performed at postoperative 24th month and the difference between the operated leg and the non-operated leg was found as a percentage deficit.

RESULTS

There were no postoperative complications, redislocation or subluxation in any patient. Kujala, Lysholm, Tegner and IKDC scores were better and statistically significant postoperatively in both groups (p < 0.05). However, there was no statistically significant difference between the groups (n.s.). The congruence angle and patellar tilt angle were found to be returned to normal values postoperatively, but there was no statistically significant difference between the groups (n.s.). There was no statistically significant difference between the two groups in isokinetic dynamometric tests performed as 60° flexion, 60° extension, 180° flexion and 180° extension (n.s.).

CONCLUSION

The present study is the first that compared the clinical, radiological and functional results of the ST and DT techniques to date. Regardless of the number of the tunnels, similar results were obtained in ST and DT reconstruction using transpatellar tunnel technique.

LEVEL OF EVIDENCE

Level I.

Instant messaging application usage for clinical consultation among orthopedic surgery residents in Turkey: A survey study

OBJECTIVE

This study aimed to determine the characteristics of instant messaging application (IMA) usage for clinical consultation among orthopedic residents in Turkey and to explore their experiences and opinions concerning potential legal problems.

METHODS

A questionnaire titled "Instant messaging for consultation among orthopedic surgeons" consisting of 21 questions was applied to orthopedic surgery residents, and the results were analyzed. The questions were designed to obtain information on 4 categories: 1) demographics and professional experience, 2) attitudes on the use of cellular phones, 3) IMA usage for clinical consultation purposes, and 4) problems and comments on smartphone application usage for clinical consultation purposes. The participants who had no experience with a smartphone or IMA usage were excluded at the final analysis.

RESULTS

A total of 860 orthopedic residents (849 males [98.7%]; mean age=28.6 years; age range=22-44 years) participated in the survey (participation rate: 97.3%). The distribution of residency years was as follows: 1st year, 27%; 2nd year, 21.4%; 3rd year, 18.4%; 4th year, 17.4%; and 5th year, 49.9%. The most frequently used IMAs were WhatsApp (99.3%), Facebook Messenger (14.8%), Viber (8%), and Tango (1.3%). The rate of IMA usage for consultation was 95.3%. The most common reasons to prefer IMAs for consultation were being "fast" and "easy," but only 26.3% of the residents reported that they prefer the use of IMAs because they find them "reliable." Moreover, 41.7% of the respondents reported that they had an experience of misdiagnosis owing to the use of IMAs; 81.2% of the participants used the personal information of the patients during the consultation; 57.6% of the respondents considered that legal problems may arise because of the use of IMAs during the consultation; and 51.4% believed that an electronic platform, solely for consultation purposes, is required.

CONCLUSION

This survey has shown that it is necessary to make some legal regulations regarding the use of IMAs for consultation purposes and to develop applications only for medical consultation purposes. Most of the trainees make decisions using IMAs without a proper examination, putting the patients at the risk of misdiagnosis. Moreover, the confidentiality of the patient's personal information appears to be in danger when IMAs are used.

LEVEL OF EVIDENCE

Level IV, Diagnostic Study.

Effect of synbiotics in the treatment of smokers and non-smokers with gingivitis: randomized controlled trial

BACKGROUND

To evaluate the efficacy of synbiotic tablets on the clinical and biochemical parameters of smokers and non-smokers with gingivitis.

METHODS

Eighty patients with gingivitis [40 smokers (+), 40 non-smokers (-)] were randomly assigned to test (T) or control (C) groups. Four groups were defined: T(+), T(-), C(+) and C(-). The subjects daily chewed a synbiotic or placebo tablet for 30 days. The gingival crevicular fluid levels of interleukin (IL)-6, IL-8 and IL-10 were determined as the primary outcome variables.

RESULTS

The clinical and biochemical parameters for all groups significantly reduced compared with the baseline (P < 0.05). While there were no significant differences between the groups for gingival index, the plaque index was significantly higher in both smoker groups than that in the T(-) group during the second month (P < 0.05). IL-8 levels in C(-) and IL-6 levels in both control groups were significantly higher than those in the T(+) group. The IL-10 levels in both control groups were significantly higher than those in the T(-) group during the second month (P < 0.05).

CONCLUSIONS

Adjunctive synbiotic tablets significantly reduce subclinical therapeutic outcomes for both smokers and non-smokers compared with placebo according to the biochemical parameters.

Determination of serum adenosine deaminase and xanthine oxidase activity in Kangal dogs with maternal cannibalism

Aim:

Kangal dogs, known as guard dogs in many countries of the world, have been found to eat their own puppies during their first 24 h following birth, which is called as maternal cannibalism. Adenosine deaminase (ADA) and xanthine oxidase (XO) are important enzymes for purine metabolism. In this study, the aim is to evaluate ADA and XO activities in Kangal dogs with maternal cannibalism.

Materials and Methods:

The material of the study consists of the blood sera of Kangal dog breed with and without maternal cannibalism in the breeders around Sivas city and its districts. ADA and XO activities in blood serum of these animals were investigated by spectrophotometric method.

Results:

ADA activities in Kangal dogs with maternal cannibalism were increased to the control group without maternal cannibalism (p<0.01).

Conclusion:

Postnatal measurement of ADA activity in dogs may be useful in assessing maternal cannibalism.

Higher P-wave dispersion in migraine patients with higher number of attacks

OBJECTIVE AND AIM

An imbalance of the sympathetic system may explain many of the clinical manifestations of the migraine. We aimed to evaluate P-waves as a reveal of sympathetic system function in migraine patients and healthy controls.

MATERIALS AND METHODS

Thirty-five episodic type of migraine patients (complained of migraine during 5 years or more, BMI < 30 kg/m²) and 30 controls were included in our study. We measured P-wave durations (minimum, maximum, and dispersion) from 12-lead ECG recording during pain-free periods. ECGs were transferred to a personal computer via a scanner and then used for magnification of x400 by Adobe Photoshop software.

RESULTS

P-wave durations were found to be similar between migraine patients and controls. Although P WD (P-wave dispersion) was similar, the mean value was higher in migraine subjects. P WD was positively correlated with P max (P < 0.01). Attacks number per month and male gender were the factors related to the P WD (P < 0.01).

CONCLUSIONS

Many previous studies suggested that increased sympathetic activity may cause an increase in P WD. We found that P WD of migraine patients was higher than controls, and P WD was related to attacks number per month and male gender. Further studies are needed to explain the chronic effects of migraine.

Allosteric regulation of liver phosphorylase a: revisited under approximated physiological conditions

Phosphorylase removes glucosyl units from the terminal branches of glycogen through phosphorolysis, forming glucose-1-P. It is present in two interconvertible forms, phosphorylase a and b. The a form is the active form and is rate limiting in glycogen degradation. The activities of phosphorylase a and of total phosphorylase as conventionally measured exceed the activities of glycogen synthase R (active form) and of total synthase by approximately 10- and 20-fold. Thus, unless phosphorylase a is inhibited or compartmentalized or its substrates are exceedingly low in vivo, net glycogen synthesis could not occur. In addition, following an administered dose of glucose, phosphorylase a activity changes little when glycogen is being synthesized, is stable, or is being degraded, suggesting an important role for allosteric effectors in regulation. Therefore, we have determined the effect of potential modifiers of enzyme activity at estimated intracellular concentrations. Purified liver phosphorylase a was used. Activity was measured in the direction of glycogenolysis, at 37 degrees C, pH 7.0, and under initial rate conditions. Both a Km and a near-saturating concentration of inorganic phosphate (substrate) were used in the assays. A physiological concentration of AMP was saturating. It decreased the Km for Pi by approximately 50% and stimulated activity. ADP, ATP, and glucose inhibited activity. Fructose-1-P inhibited activity only at a high and nonphysiological concentration. Glucose-6-P and UDP-glucose were not significant inhibitors. Inhibition of activity by ADP was little affected by the addition of AMP. However, AMP partially abolished the inhibitory effect of ATP and completely abolished the inhibitory effect of glucose. When AMP, ADP, ATP, glucose-6-P, UDP-glucose, glucose, and fructose-1-P were added together, the net effect was no change in phosphorylase a activity compared to the activity without any effectors. In addition, changes in glucose concentration did not affect activity. K glutamine modestly stimulated activity. Numerous other metabolites were tested and were without effect. The present data indicate that the known endogenous allosteric effectors cannot explain the smaller than expected in vivo phosphorylase a activity or the regulation of phosphorylase a activity.

Effects of glucagon with or without insulin administration on liver glycogen metabolism

Rats fed ad libitum were given insulin alone (4 U/kg), glucagon alone (25 micrograms/kg), or insulin and glucagon sequentially. Phosphorylase a and synthase R activities, hepatic glycogen, uridine diphosphoglucose, inorganic phosphate (Pi), and plasma glucose, lactate, glucagon, and insulin concentrations were determined over the subsequent 40 min. In separate animals, muscle extraction of 2-deoxy-D-[3H]glucose also was determined. After glucagon administration, glycogen phosphorylase a and plasma glucose were increased within 5 min. However, the glycogen concentration did not decrease for 20 min. Glucagon administration to rats pretreated with insulin stimulated a similar increase in phosphorylase a activity. Again, glycogen was not degraded for 20 min. After insulin only, glycogen concentration remained unchanged. Plasma glucose decreased as expected. In each group, muscle extraction of 2-deoxy-D-[3H]glucose increased compared with the controls (P < 0.05). In summary, glucagon and/or insulin administration did not stimulate significant glycogen degradation for 20 min, even though phosphorylase was activated. The mechanism remains to be determined.

Effect of added fat on the plasma glucose and insulin response to ingested potato given in various combinations as two meals in normal individuals

OBJECTIVE

In normal subjects, ingestion of fat with potato in a morning meal resulted in a decrease in the glucose response. Therefore, we wished to determine whether a fat-induced decrease in blood glucose also would be observed after a second identical meal. In addition, we were interested in determining if fat ingestion with a morning meal would have an effect on the blood glucose and insulin responses to a second meal not containing fat.

RESEARCH DESIGN AND METHODS

Nine healthy male subjects ingested two meals consisting of an amount of potato containing 50 g carbohydrate, either alone or with 50 g fat as butter. The meals were served in four combinations as follows: 1) potato for the first meal, potato for the second meal; 2) potato for the first meal, potato with fat for the second meal; 3) potato with fat for the first meal, potato for the second meal; and 4) potato with fat for the first meal, potato with fat for the second meal. Meals were ingested at 8:00 A.M. and noon. Plasma glucose and C-peptide, serum insulin, triglyceride, and free fatty acid (FFA) concentrations were determined over an 8-h period. The integrated area responses to the meals were quantified over the subsequent 4-h period using the fasting value or the noon value as baseline for the first and second meals, respectively.

RESULTS

When the first meal contained potato only, the glucose area response to the second meal was significantly less when the second meal contained fat. However, fat ingestion had no effect on the glucose area response to the second meal when fat was present in the first meal. The insulin area responses to the first and second meals were similar after ingestion of potato or potato with fat. However, the insulin response to the second meal always was less than that to the first meal. The C-peptide area responses after ingestion of the second meal also were all higher than those after the first meal. The triglyceride area responses were slightly negative after ingestion of potato alone in the first meal. When fat was ingested, they were positive. When the first meal contained fat but the second meal did not, there was a rise in triglyceride concentration after the second meal as well as after the first meal. That is, a rise occurred without ingestion of fat with the second meal. If fat was present in the second meal the rise was even greater. The FFA area responses were similar to the triglyceride area responses.

CONCLUSIONS

When fat was ingested with carbohydrate in either the first or second meal, the glucose area response was decreased. However, when both meals contained fat, a decrease in the glucose area response did not occur with the second meal. The glucose area responses all were greater after the second meal compared with those after the first meal, i.e., the opposite of a Staub-Traugott effect was observed. The insulin area responses to the first and second meals were similar whether fat was ingested or not.

Liver glycogen synthase, phosphorylase, and the glycogen concentration in rats given a glucose load orally: a 24-hour study

Fasted rats were given 4 g/kg glucose orally. Synthase R (active forms), total synthase, and phosphorylase alpha activities, and hepatic glycogen, glucose 6-phosphate (glucose-6P), uridine diphosphoglucose (UDP-glucose), glucose, and plasma glucose concentrations were determined over the subsequent 24 h. The resulting glycogen concentration changes could be divided into three distinct phases. A glycogen synthetic phase (between 0 and 4 h), a stability phase (between 4 and 12 h), and a degradation phase (between 12 and 24 h). Synthase R activity increased rapidly and reached a maximum at 20 min. With the onset of glycogen synthesis it gradually decreased below the control values, reaching a nadir by 4 h. During the glycogen stability phase it gradually increased again up to the control value. It then remained stable during the subsequent glycogen degradation phase. Phosphorylase a activity did not change throughout the entire 24-h period. Glucose-6-P concentration increased almost twofold at 20 min. It then decreased but was above the control values at the 24th h. The plasma and hepatic glucose concentrations increased as expected after the glucose load. They then decreased but remained above the control value at all subsequent time points. In summary, the synthase R, phosphorylase a activities, or changes in the known allosteric modifiers of these enzymes could not explain the changes in glycogen concentration. The reasons for these discrepancies remain to be determined.

Incorporation of glycogenin into a hepatic proteoglycogen after oral glucose administration

Glycogenin is a 37-kDa protein upon which new glycogen molecules are considered to be constructed. Therefore, we were interested in determining its role in liver glycogen synthesis following glucose administration. Twenty-four-hour fasted rats were given 4 g/kg glucose orally. Glycogenin and synthase R activities and glycogen were determined over the subsequent 24 h. In fasted rats given just water, glycogenin activity was present and did not change over the subsequent 24 h. Following glucose, glycogenin activity also was not different for 1 h, i.e. the glycogenin was not incorporated into glycogen even though the glycogen concentration had increased. Subsequently, the glycogenin activity became unmeasurable. Presumably, the glycogenin was incorporated into a proteoglycan product since after amylase treatment, glycogenin activity was again present and was quantitatively unchanged. Free glycogenin activity remained unmeasurable until after 12 h. At this time, glycogen began to decrease, and, by 15 h, free glycogenin activity again appeared. The results indicate that in fasted rats, essentially all of the glycogenin was free. Following administration of oral glucose, glycogenin was incorporated into a proteoglycan product but only 60 min after glycogen synthesis had begun. Free glycogenin did not reappear until the 15th h after glucose was given and after the glycogen concentration had decreased by approximately 60%.

Effects of glucose, galactose, and lactose ingestion on the plasma glucose and insulin response in persons with non-insulin-dependent diabetes mellitus

Galactose usually is ingested as lactose, which is composed of equimolar amounts of glucose and galactose. The contribution of galactose to the increase in glucose and insulin levels following ingestion of equimolar amounts of galactose and glucose, or lactose, has not been reported in people with non-insulin-dependent diabetes mellitus (NIDDM). Therefore, we studied the effects of galactose ingestion alone, as well as with glucose either independently or in the form of lactose, in subjects with untreated NIDDM. Eight male subjects with untreated NIDDM ingested 25 g glucose, 25 g galactose with or without 25 g glucose, or 50 g lactose as a breakfast meal in random sequence. They also received 50 g glucose on two occasions as a reference. Water only was given as a control meal. Plasma galactose, glucose, glucagon, alpha-amino nitrogen (AAN), nonesterified fatty acids (NEFA), and serum insulin and C-peptide concentrations were determined over a 5-hour period. The integrated area responses were quantified over the 5-hour period using the water control as a baseline. Following ingestion of 25 g galactose, the maximal increase in plasma galactose concentration was 1 mmol/L. The mean maximal increases in plasma galactose concentration following ingestion of 25 g galactose + 25 g glucose or following 50-g lactose meals were similar and were only 12% of that following ingestion of galactose alone (P < .05). The mean galactose area response over the water control for the 25-g galactose meal was 0.95 +/- 0.31 mmol.h/L.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma glucose and insulin responses to bananas of varying ripeness in persons with noninsulin-dependent diabetes mellitus

With progressive ripeness there is a decrease in starch and an increase in free sugar content of bananas. The starch also is considered to be poorly digestible. Therefore, we decided to study plasma glucose, serum insulin, C-peptide, and plasma glucagon responses to bananas with increasing degrees of ripeness. Seven male subjects with untreated noninsulin-dependent diabetes mellitus ingested 50 g carbohydrate as bananas of stage 4 (more yellow than green), 5 (yellow with green tip), 6 (all yellow), and 7 (yellow flecked with brown) ripeness. They also received 50 glucose on two occasions for comparative purposes. On a separate occasion water only was given as a control. The area responses were quantified by determining incremental areas using the water control as baseline. The mean glucose area following the 50 g glucose meals was 15.1 +/- 1.9 mM.h. After the ingestion of bananas of 4, 5, 6 and 7 ripeness the glucose area response was 42, 41, 51 and 48% of that after glucose ingestion, respectively. The insulin area response following glucose meals was 888 pM.h. Responses to 4, 5, 6 and 7 bananas were 85, 70, 61, 85%, respectively, of that following glucose ingestion. C-peptide data were similar to the insulin data. The glucagon area response was negative after glucose ingestion but was positive following banana ingestion. In summary, the glucose, insulin, C-peptide, and glucagon area responses varied little with ripeness of the bananas.

Effect of added fat on plasma glucose and insulin response to ingested potato in individuals with NIDDM

OBJECTIVE

In normal subjects, ingestion of butter with potato resulted in considerably lower blood glucose levels but similar or higher insulin concentrations compared with those observed in the same subjects after potato ingestion alone. We determined whether butter ingested with potato would result in a greater stimulation in insulin secretion than ingestion of potato alone in subjects with NIDDM.

RESEARCH DESIGN AND METHODS

Seven male subjects with untreated NIDDM ingested 50 g CHO alone or 50 g CHO with 5, 15, 30, or 50 g fat as a breakfast meal. Fat was ingested in the form of butter, and CHO was given in the form of potato. Subjects received 50 g glucose on two separate occasions for comparative purposes. The subjects also were given only water and were studied over the same time period (water control). Plasma glucose, glucagon, alpha-amino nitrogen, nonesterified fatty acids, serum insulin, C-peptide, and triglyceride concentrations were determined over 5 h. The integrated area responses were quantified over the 5-h period using the water control as a baseline.

RESULTS

The mean plasma glucose area response after ingestion of potato with or without the various amounts of butter were all similar and were 82% of that observed after ingestion of 50 g glucose. The mean insulin area response to potato alone was 532 pmol.h.L-1. The mean insulin area responses to potato plus 5,15,30, and 50 g of fat meals were 660,774,750, and 756 pmol.h.L-1, respectively. Thus, the mean insulin areas were all greater than for ingestion of potato alone, and a maximal response was observed with addition of 15 g fat (1.4-fold). The C-peptide data did not confirm an increase in insulin secretion. Overall the area responses after ingestion of meals containing fat were not different from the response to potato ingestion alone, although the responses were erratic. The glucagon area response was positive after ingestion of all fat containing meals except for that containing only 5 g fat, and there was a dose-response relationship. The plasma alpha-amino nitrogen and nonesterified fatty acid area responses were negative after potato ingestion and were not significantly different when fat was added. The serum triglyceride concentration increase was greater after the ingestion of butter with the potato as expected.

CONCLUSIONS

In contrast to the results in normal subjects after ingestion of butter with potato, the glucose response was not smaller in subjects with NIDDM. The insulin response was greater. The insulin area response data indicated the presence of a dose-response relationship. Whether similar responses will be observed with other dietary fat and CHO sources remains to be determined.