Oxidant/Antioxidant Status in Cases of Snake Bite

Background

Snake bites are an important cause of mortality and morbidity worldwide, especially in rural areas.

Objective

The aim of this study was to investigate serum paraoxonase (PON), arylesterase (ARLY), ceruloplasmin (Cp), and myeloperoxidase (MPO) activity and lipid hydroperoxide (LOOH) and total sulfhydryl group (-SH) levels in patients with snake venom poisoning.

Methods

The study included 49 patients with snake bite envenomation (Group 1) and 39 healthy volunteers as the control group (Group 2). Plasma PON, ARLY, Cp, and MPO activity and LOOH and -SH levels were measured. Laboratory measurements of 20 patients with snake bite envenomation (Group 3) were performed again after treatment.

Results

PON and ARLY activity and -SH levels were significantly decreased in Group 1 compared with those in Group 2. Cp and MPO activity and LOOH levels were significantly elevated in Group 1 compared with those in Group 2. PON and ARLY activity were significantly elevated in Group 3 compared with those in Group 1. Cp and MPO activity and LOOH levels were significantly decreased in Group 3 compared with those in Group 1.

Conclusions

Patients with snake bite envenomation had increased oxidants (MPO and LOOH) and decreased antioxidants (PON, ARLY, and -SH). Results obtained in this study demonstrate that snake bites are associated with a shift to oxidative status. Therapy with antioxidants can lead to an increase in the antioxidant defense system, and thus improvements in clinical symptoms.     

Thyroid hormone alterations in trauma patients requiring massive transfusion: An observational study

BACKGROUND:

Although non-thyroidal illness syndrome (NTIS) is considered a negative prognostic factor, the alterations in free triiodothyronine (fT3) levels in trauma patients requiring massive transfusion have not been reported.

METHODS:

A prospective observational study comparing 2 groups of trauma patients was conducted. Group M comprised trauma patients requiring massive transfusions (>10 units of packed red blood cells) within 24 hours of emergency admission. Group C comprised patients with an injury severity score >9 but not requiring massive transfusions. Levels of fT3, free thyroxine (fT4), and thyroid-stimulating hormone (TSH) were evaluated on admission and on days 1, 2, and 7 after admission. The clinical backgrounds and variables measured including total transfusion amounts were compared and the inter-group prognosis was evaluated. Results are presented as mean±standard deviation.

RESULTS:

Nineteen patients were enrolled in each group. In both groups, 32 were men, and the mean age was 50±24 years. In group C one patient died from respiratory failure. The initial fT3 levels in group M (1.95±0.37 pg/mL) were significantly lower than those in group C (2.49±0.72 pg/mL; P<0.01) and remained low until 1 week after admission. Initial inter-group fT4 and TSH levels were not significantly different. TSH levels at 1 week (1.99±1.64 µIU/mL) were higher than at admission (1.48±0.5 µIU/mL) in group C (P<0.05).

CONCLUSION:

Typical NTIS was observed in trauma patients requiring massive transfusions. When initial resuscitation achieved circulatory stabilization, prognosis was not strongly associated with NTIS.KEY WORDS: Non-thyroidal illness syndrome, Massive transfusion, Trauma, Free triiodothyronine, Thyroid hormone     

A minimally invasive multiple percutaneous drainage technique for acute necrotizing pancreatitis

BACKGROUND:

In approximately 20% of patients, necrotizing pancreatitis is complicated with severe acute pancreatitis, with high morbidity and mortality rates. Minimally invasive step-up approach is both safe and effective, but sometimes requires multiple access sites.

METHODS:

A 62-year-old woman was admitted with diabetic ketoacidosis, and initial computed tomography (CT) revealed no evidence of acute pancreatitis. She was clinically improved with insulin therapy, fluid administration, and electrolyte replacement. However, on the 14^th day of admission, she developed a high-grade fever, and CT demonstrated evidence of acute necrotizing pancreatitis with a large collection of peripancreatic fluid. Percutaneous transgastric drainage was performed and a 14 French gauge (Fr) pigtail catheter was placed 1 week later, which drained copious pus. Because of persistent high-grade fever and poor clinical improvement, multiple 8 and 10 Fr pigtail catheters were placed via the initial drainage route, allowing the safe and effective drainage of the extensive necrotic tissue that was occupying the bilateral anterior pararenal space.

RESULTS:

After drainage, the patient recovered well and the last catheter was removed on day 123 of admission.

CONCLUSIONS:

Multiple percutaneous drainage requires both careful judgment and specialist skills. The perforation of the colon and small bowel as well as the injury of the kidney and major vessels can occur. The current technique appears to be safe and minimally invasive compared with other drainage methods in patients with extended, infected necrotic pancreatic pseudocysts.KEY WORDS: Percutaneous drainage, Acute necrotizing pancreatitis, Minimally invasive technique     

Homocysteinethiolactone and Paraoxonase: Novel markers of diabetic retinopathy

OBJECTIVE

Paraoxonase (PON) exhibits esterase activity (PON-AREase) and lactonase activity (PON-HCTLase), which prevent LDL oxidation and detoxify homocysteine thiolactone (HCTL). The role of HCTL and PON-HCTLase as a risk factor for the microvascular complication in diabetic retinopathy at the level of vitreous has not been investigated.

RESEARCH DESIGN AND METHODS

Undiluted vitreous from patients with proliferative diabetic retinopathy (PDR) (n = 13) and macular hole (MH) (n = 8) was used to determine PON-HCTLase and PON-AREase activity spectrophotometrically. HCTL levels were detected by liquid chromatography–tandem mass spectrometry. In vitro studies were done in primary cultures of bovine retinal capillary endothelial cells (BRECs) to determine the dose- and time-dependent effect of HCTL and homocysteine (Hcys) on PON-HCTLase activity, as well as to determine mRNA expression of PON by RT-PCR.

RESULTS

A significant increase in HCTL and PON-HCTLase activity was observed in PDR compared with MH (P = 0.036, P = 0.001), with a significant positive correlation between them (r = 0.77, P = 0.03). The in vitro studies on BRECs showed a dose- and time-dependent increase in the PON-HCTLase activity and mRNA expression of PON2 when exposed to HCTL and Hcys.

CONCLUSIONS

This is the first study showing elevated levels of vitreous HCTL and PON-HCTLase activity in PDR. These elevations are probably a protective effect to eliminate HCTL, which mediates endothelial cell dysfunction. Thus, vitreous levels of HCTL and PON activity can be markers of diabetic retinopathy. The bioinformatics analysis reveals that the structure and function of PON that can be modulated by hyperhomocysteinemia in PDR can affect the dual-enzyme activity of PON.Hyperhomocysteinemia is a well-established independent risk factor for the development of macrovascular and microvascular diseases (1). Recent reports show that increased homocysteine thiolactone (HCTL) levels are associated with diabetic macrovasculopathy (2). HCTL is formed in all cell types as a result of error-editing met-tRNA synthetase when there is excess homocysteine (Hcys). The interaction of HCTL with proteins leads to protein homocysteinylation and loss of function (3). Therefore, detoxification of HCTL is crucial. This is possible by the lactonase (HCTLase) activity of paraoxonase (PON) (4). The enzyme PON is a calcium-dependent 45-kDa protein coded by chromosome 7q21-22. The PON gene family in humans has three members: PON1, PON2, and PON3. Whereas PON1 and PON3 are associated with serum HDL (5), PON2 is ubiquitously expressed in tissues (6). PON1 exhibits antioxidant properties, thereby preventing the accumulation of oxidized LDL, and PON2 acts mainly at the cellular level (7). Lipid oxidation plays a role not only in macrovascular diseases but also in microvascular dysfunction, and serum PON1 activity was decreased in patients with diabetic retinopathy (8). While elevated Hcys in the vitreous of patients with proliferative diabetic retinopathy (PDR) was reported by us and others (9,10), there are no reports on HCTL levels and PON activity. This study aims to detect the vitreous levels of HCTL, PON-HCTLase, and esterase (PON-AREase) activity in PDR case subjects and in in vitro studies in bovine retinal capillary endothelial cells (BRECs).     

Effect of hypertransfusion on the gastrointestinal tract after cardiac arrest in a porcine model

BACKGROUND:

This study aimed to determine the potential protective effect of inducing hypertransfusion to the gastrointestinal tract following a porcine model of cardiac arrest and cardiopulmonary resuscitation (CPR) by evaluating the influence of gastrointestinal ultrastructure, ATPase and serum diamine oxidase.

METHODS:

Ventricular fibrillation was induced by programmed electrical stimulation in 16 male domestic pigs (n=8/group). Four minutes after ventricular fibrillation, CPR was performed. The pigs that successfully restored spontaneous circulation received intravenous infusion of either norepinephrine to maintain the mean arterial pressure at 130% of the baseline before ventricular fibrillation or normal saline. Serum diamine oxidase and gastrointestinal ATPase activity were determined, and histopathological examination of the gastrointestinal tract was performed by light and electron microscopy.

RESULTS:

CPR caused significant injury to the gastrointestinal tract, elevating serum diamine oxidase and causing destruction of intestinal microvillus in control animals. Na⁺-K⁺ ATPase and Ca²⁺ ATPase activity in gastric tissue were significantly elevated in animals receiving hypertransfusion treatment compared with the control animals. Hypertransfusion also significantly reduced serum diamine oxidase to below control levels after CPR. Moreover, severe injury sustained by the gastrointestinal tissue was markedly ameliorated under hypertransfusion conditions compared with the control animals.

CONCLUSIONS:

Gastrointestinal injury and abnormal energy metabolism were strikingly evident following CPR. Hypertransfusion inducing hypertension can improve energy metabolism and ameliorate gastrointestinal mucosal injury, indicating that hypothermia significantly ameliorates gastrointestinal injury sustained following cardiac arrest.KEY WORDS: Cardiopulmonary resuscitation, Cardiac arrest, Gastrointestinal tract, Diamine oxidase, Ultra structure     

Serum Paraoxonase 1 Activity and Oxidative Stress in Pediatric Patients with Pulmonary Tuberculosis

Objectives

The aim of this study was to determine the oxidative stress and paraoxonase 1 (PON1) levels in children with pulmonary tuberculosis (TB) compared to healthy controls, and to examine the association of demographical with oxidative stress.

Subjects and Methods

Forty children diagnosed with pulmonary TB and 40 age- and gender-matched healthy controls were enrolled in the study. Serum total antioxidant status (TAS), total oxidant status (TOS) and PON1 levels were measured. The oxidative stress index (OSI) was calculated to indicate the degree of oxidative stress.

Results

The TAS levels were lower (1.73 ± 0.5 vs. 2.54 ± 1.2 μmol Trolox Eq/l) while TOS levels were significantly higher (26.9 ± 14.4 vs. 13.4 ± 7.7 μmol H₂O₂ Eq/l) in the TB group than in the controls (p < 0.001). The OSI was significantly higher in the TB group than in the controls (21.2 ± 5.1 vs. 6.5 ± 4.9 units, p = 0.006). Serum PON1 levels were significantly lower in the TB group than in the controls (14.2 ± 13.2 vs. 28.4 ± 17.3 U/l, p < 0.001). The lower PON1 levels correlated with TAS and OSI levels but not with anthropometric parameters (r = 0.264, p = 0.018 and r = −0.255, p = 0.023, respectively).

Conclusion

The TOS and OSI levels were higher and the TAS and PON1 levels were lower in pediatric patients with pulmonary TB when compared to healthy controls. This indicates greater oxidative stress in the patients.Key Words: Total oxidant status, Paraoxonase 1, Tuberculosis, Oxidative stress     

Suicidal ingestion of potassium permanganate

BACKGROUND:

Potassium permanganate is used clinically as an antiseptic and antifungal agent. Ingestion of potassium permanganate may result in damage to the upper gastrointestinal tract. Burns and ulceration of the mouth, esophagus and stomach occur due to its action. Emergency endoscopy is useful to assess the severity of damage and also to guide management.

METHODS:

We reported a patient presenting to the emergency department after suicidal ingestion of potassium permanganate.

RESULTS:

After treatment, the patient was discharged home on the 7th day after admission.

CONCLUSION:

Early emergency endoscopy should be considered to determine the extent of upper gastrointestinal damage in the emergency department.KEY WORDS: Emergency endoscopy, Gastric damage, Suicide, Potassium permanganate     

B-type natriuretic peptide in predicting the severity of community-acquired pneumonia

BACKGROUND: Although pneumonia severity index(PSI) is widely used to evaluate the severity of community-acquired pneumonia(CAP), the calculation of PSI is very complicated. The present study aimed to evaluate the role of B-type natriuretic peptide(BNP) in predicting the severity of CAP.METHODS: For 202 patients with CAP admitted to the emergency department, BNP levels, cardiac load indexes, inf lammatory indexes including C-reactive protein(CRP), white blood cell count(WBC), and PSI were detected. The correlation between the indexes and PSI was investigated. BNP levels for survivor and non-survivor groups were compared, and a receiver operating characteristic(ROC) curve analysis was performed on the BNP levels versus PSI.RESULTS: The BNP levels increased with CAP severity(r=0.782, P0.001). The BNP levels of the high-risk group(PSI classes IV and V) were signifi cantly higher than those of the low-risk group(PSI classes I–III)(P0.001). The BNP levels were signifi cantly higher in the non-survivor group than in the survivor group(P0.001). In addition, there were positive correlations between BNP levels and PSI scores(r=0.782, P0.001). The BNP level was highly accurate in predicting the severity of CAP(AUC=0.952). The optimal cut-off point of BNP level for distinguishing high-risk patients from low-risk ones was 125.0 pg/m L, with a sensitivity of 0.891 and a specifi city of 0.946. Moreover, BNP level was accurate in predicting mortality(AUC=0.823). Its optimal cut-off point for predicting death was 299.0 pg/m L, with a sensitivity of 0.675 and a specifi city of 0.816. Its negative predictive cut-off value was 0.926, and the positive predictive cut-off value was 0.426.CONCLUSION: BNP level is positively correlated with the severity of CAP, and may be used as a biomarker for evaluating the severity of CAP.     

Effect of platelet–lymphocyte ratio and lactate levels obtained on mortality with sepsis and septic shock

Background

Sepsis is a potentially fatal condition with high treatment costs, and is especially common among the elderly population. The emergency management of septic patients has gained importance.

Protective effect of glutamine in critical patients with acute liver injury

BACKGROUND:

Glutamine (Gln) supplementation is known to decrease oxidative stress and inflammatory response, enhance resistance to infectious pathogens, shorten hospital stay, and decrease medical costs of patients. This study was undertaken to evaluate the relationship between the effect of early parenteral glutamine (Gln) supplement on acute liver injury (ALI) and heat shock protein 70 (HSP-70) expression in critical patients.

METHODS:

Forty-four patients who had been admitted to the emergency intensive care unit (EICU) of Nanjing First Hospital Affiliated to Nanjing Medical University were randomly divided into a control group (n=22) and a Gln group (n=22). The patients of the two groups received enteral and parenteral nutrition. In addition, parenteral Gln 0.4 g/kg per day was given for 7 days in the Gln group. Serum HSP-70 and Gln were measured at admission and at 7 days after admission. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TBiL), serum levels of HSP-70 and Gln, mechanical ventilation (MV) time, ICU stay, peripheral blood of TNF-α, IL-6, CD3, CD4 and CD4/CD8 levels were also measured in the two groups.

RESULTS:

In the Gln group, the levels of serum HSP-70 and Gln were significantly higher after Gln treatment than those before the treatment (P<0.01). HSP-70 level was positively correlated with the Gln level in the Gln group after administration of parenteral Gln (P<0.01). The levels of serum ALT, AST, TBiL and TNF-α, IL-6 were lower in the Gln group than in the non-Gln group (P<0.01). MV time and ICU stay were significantly different between the two groups (P<0.05). The levels of CD3, CD4 and CD4/CD8 were significantly higher in the Gln group than in the control group after treatment (P<0.05).

CONCLUSION:

Parenteral Gln significantly increases the level of serum HSP70 in critically ill patients. The enhanced expression of HSP70 is correlated with improved outcomes of Gln-treated patients with acute liver injury.KEY WORDS: Glutamine, Heat shock protein, Critically ill patients, Acute liver injury     

Variation in hospital admission rates between a tertiary care and two freestanding emergency departments

Background

Recently, freestanding emergency departments (FSEDs) have grown significantly in number. Critics have expressed concern that FSEDs may increase healthcare costs.

Effect of Comprehensive Postural Instructions and Range of Motion Exercises Via Educational Videos on Motor Function and Shoulder Injury in Stroke Patients With Hemiplegia: A Preliminary Study

Objective

The purpose of this study was to investigate the effect of comprehensive postural instructions and range of motion (ROM) exercises via educational videos for shoulder injury prevention and functional improvement of the hemiplegic shoulder after acute stroke.

Fetal circulation in left-sided congenital heart disease measured by cardiovascular magnetic resonance: a case–control study

Background

The distribution of blood flow in fetuses with congenital heart disease (CHD) is likely to influence fetal growth, organ development, and postnatal outcome, but has previously been difficult to study. We present the first measurements of the distribution of the fetal circulation in left-sided CHD made using phase contrast cardiac magnetic resonance (CMR).

Methods

Twenty-two fetuses with suspected left-sided CHD and twelve normal controls underwent fetal CMR and echocardiography at a mean of 35 weeks gestation (range 30–39 weeks).

Results

Fetuses with left-sided CHD had a mean combined ventricular output 19% lower than normal controls (p < 0.01). In fetuses with left-sided CHD with pulmonary venous obstruction, pulmonary blood flow was significantly lower than in those with left-sided CHD without pulmonary venous obstruction (p < 0.01). All three fetuses with pulmonary venous obstruction had pulmonary lymphangectasia by fetal CMR and postnatal histology. Fetuses with small but apex forming left ventricles with left ventricular outflow tract or aortic arch obstruction had reduced ascending aortic and foramen ovale flow compared with normals (p < 0.01). Fetuses with left-sided CHD had more variable superior vena caval flows than normal controls (p < 0.05). Six fetuses with CHD had brain weights at or below the 5^th centile for gestational age, while none of the fetuses in the normal control group had brain weights below the 25^th centile.

Conclusions

Measurement of the distribution of the fetal circulation in late gestation left-sided CHD is feasible with CMR. We demonstrated links between fetal blood flow distribution and postnatal course, and examined the relationship between fetal hemodynamics and lung and brain development. CMR enhances our understanding of pathophysiology of the fetal circulation and, with more experience, may help with the planning of perinatal management and fetal counselling.     

Treatment of vitamin K-dependent coagulation factor deficiency and subarachnoid hemorrhage

BACKGROUND:

In adults, vitamin K-dependent coagulation factor deficiency (VKCFD) increases in the recent years. We treated a VKCFD patient with subarachnoid hemorrhage, with favorable outcomes.

METHODS:

A 19-year-old male student with VKCFD was treated at our hospital. The initial treatment was injection of a large dose of vitamin K and fresh plasma, and then with oral high dose of vitamin K4.

RESULTS:

At 4 weeks after admission, the focus of hemorrhage subsided, neurological examination was normal, and the patient was discharged.

CONCLUSIONS:

VKCFD is rare and its diagnosis should be based on the history of the patient and the results of laboratory examinations. A large dose of vitamin K is the first choice of treatment.KEY WORDS: Vitamin K-dependent coagulation factor deficiency, Subarachnoid hemorrhage, Diagnosis     

Artificial liver support system in treatment of liver failure after acute poisoning

BACKGROUND:

Acute poisoning (AP) may cause failure of the liver and kidney, and even death. This study aimed to investigate the efficacy of artificial liver support system (ALSS) on the treatment of liver failure after acute poisoning.

METHODS:

A total of 31 patients with liver failure caused by AP were admitted to emergency ICU, central ICU, and Department of Gastroenterology from 2005 to 2009 in Zhongshan Hospital Affiliated to Xiamen University, China. Among them, 13 patients served as a treatment group, and used ALSS in addition to detoxification treatment and protective treatment of liver function, and the other 18 patients served as a control group receiving detoxification treatment and protective treatment of liver function.

RESULTS:

In the treatment group, 10 patients (76.9%) were cured or improved, 2 died, and 1 was discharged against advice. In the 18 patients in the control group, 7 (38.9%) were cured or improved, 3 died, and 8 were discharged against advice. There was a significant difference in the rates of improvement between the two groups (P<0.05).

CONCLUSION:

ALSS is a safe and effective clinical method for the treatment of acute toxic liver failure.KEY WORDS: Toxicity, Liver failure, Artificial liver support system     

Are testers also admitters? Comparing emergency physician resource utilization and admitting practices

Objective

To describe the relationship between emergency department resource utilization and admission rate at the level of the individual physician.

Effect of spironolactone on cardiac remodeling after acute myocardial infarction

BACKGROUND:

Few studies have reported the effect of aldosterone receptor antagonist (ARA) on myocardial remodeling after acute myocardial infarction (AMI). This study was undertaken to investigate the preventive effect of ARA on myocardial remodeling after AMI.

METHODS:

A total of 616 patients who had been admitted into the CCU of the First Affiliated Hospital of Harbin Medical University from January 2008 to January 2010 were studied prospectively. Only 528 patients were observed completely, including 266 of the control group and 262 of the treatment group. There was no statistical difference in age, gender, medical history, admission situation, and treatment between the two groups (P>0.05). The preventive effects of spironolactone on cardiac remodeling, left ventricular function, renal function and blood levels of potassium were evaluated by echocardiography, serum potassium and serum creatinine at one-month and one-year follow-up.

RESULTS:

The echocardiography indicators such as LVESD, LVEDD, LVEF, LAD-ML and LAD-SI were significantly improved in the treatment group compared with the control group at one year (P<0.05). In the treatment group, LVESD, LVEDD, LVPWT, LVEF, LAD-ML and LAD-SI were more significantly improved at one year than one month (P<0.05, P=0.007 to LVEF), and in the control group LVEF was more significantly improved at one year than one month (P=0.0277). There were no significant differences in serum potassium and serum creatinine levels between the two groups.

CONCLUSION:

On the basis of conventional treatment, the early combination of low-dose spironolactone (20 mg/d) could inhibit cardiac remodeling at late stage and prevent heart failure.KEY WORDS: Myocardial infarction, acute, Ventricular remodeling, Atrial remodeling, Aldosterone, Aldosterone blockade, Spironolactone, Cardiac function, Prognosis     

Effect of ulinastatin on paraquat-induced-oxidative stress in human type II alveolar epithelial cells

BACKGROUND:

Ulinastatin (UTI) is a urinary trypsin inhibitor extracted and purified from urine of males. This study aimed to explore the effects of UTI on paraquat-induced-oxidative stress in human type II alveolar epithelial cells.

METHODS:

The human type II alveolar epithelial cells, A549 cells, were cultured in vitro. The A549 cells were treated with different concentrations of paraquat (200, 400, 600, 800, 1 000, 1 200 µmol/L) and ulinastatin(0, 2 000, 4 000, 6 000, 8 000 U/mL) for 24 hours, the cell viability was measured by cell counting kit-8 and the median lethal concentration was selected. In order to establish an in vitro model of paraquat intoxication and to determine the safe dose of ulinastatin, we calculated LD50 using cell counting kit-8 to determine the survival rate of the cells. A549 cells were divided into normal control group, paraquat group and paraquat+ulinastatin group. The levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were detected by biochemistry colorimetry, while the level of reactive oxygen spies (ROS) was detected by DCFH-DA assay.

RESULTS:

The survival rate of A549 cells treated with different concentrations of paraquat decreased in a concentration-dependent manner. Whereas there was no decrease in the survival rate of cells treated with 0–4 000 U/mL ulinastatin. The levels of MDA, MPO, and ROS were significantly higher in the paraquat group than in the normal control group after 24-hour-exposure. And the survival rate of the paraquat+ulinastatin group was higher than that of the paraquat group, but lower than that of the normal control group. The levels of MDA, MPO, and ROS were lower than those of the paraquat group.

CONCLUSION:

Ulinastatin can alleviate the paraquat-induced A549 cell damage by reducing oxidative stress.KEY WORDS: Ulinastatin, Paraquat, Oxidative stress, A549 cell     

Comparative Study of Glucose Homeostasis,Lipids and Lipoproteins,HDL Functionality,and Cardiometabolic Parameters in Modestly Severely Obese African Americans and White Americans With Prediabetes: Implications for the Metabolic Paradoxes

OBJECTIVE

To determine whether modestly severe obesity modifies glucose homeostasis, levels of cardiometabolic markers, and HDL function in African Americans (AAs) and white Americans (WAs) with prediabetes.

RESEARCH DESIGN AND METHODS

We studied 145 subjects with prediabetes (N = 61 WAs, N = 84 AAs, mean age 46.5 ± 11.2 years, mean BMI 37.8 ± 6.3 kg/m²). We measured fasting levels of lipids, lipoproteins, and an inflammatory marker (C-reactive protein [CRP]); HDL functionality (i.e., levels of paraoxonase 1 [PON1]); and levels of oxidized LDL, adiponectin, and interleukin-6 (IL-6). We measured serum levels of glucose, insulin, and C-peptide during an oral glucose tolerance test. Values for insulin sensitivity index (Si), glucose effectiveness index (Sg), glucose effectiveness at zero insulin (GEZI), and acute insulin response to glucose (AIR_g) were derived using a frequently sampled intravenous glucose tolerance test (using MINMOD software).

RESULTS

Mean levels of fasting and incremental serum glucose, insulin, and C-peptide tended to be higher in WAs versus AAs. The mean Si was not different in WAs versus AAs (2.6 ± 2.3 vs. 2.9 ± 3.0 × 10⁻⁴ × min⁻¹ [μU/mL]⁻¹). Mean values for AIR_g and disposition index as well as Sg and GEZI were lower in WAs than AAs. WAs had higher serum triglyceride levels than AAs (116.1 ± 55.5 vs. 82.7 ± 44.2 mg/dL, P = 0.0002). Mean levels of apolipoprotein (apo) A1, HDL cholesterol, PON1, oxidized LDL, CRP, adiponectin, and IL-6 were not significantly different in obese AAs versus WAs with prediabetes.

CONCLUSIONS

Modestly severe obesity attenuated the ethnic differences in Si, but not in Sg and triglyceride levels in WAs and AAs with prediabetes. Despite the lower Si and PON1 values, AAs preserved paradoxical relationships between the Si and HDL/apoA1/triglyceride ratios. We conclude that modestly severe obesity has differential effects on the pathogenic mechanisms underlying glucose homeostasis and atherogenesis in obese AAs and WAs with prediabetes.