Iranian Journal of

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Background: Chronic complications of diabetes causes substantial mortality and morbidity. The incidence and rate of progression of these complications depends on ethnic factors. The aim of this study was to investigate the incidence of late complications of diabetes and its relation to blood glucose control in a group of diabetic patients from South of Iran.
Methods: In this retrospective study, medical records of all diabetic patients who were followed regularly during a 12 year period at outpatient clinics of Shiraz University of Medical Sciences were investigated. Information regarding age, sex, type of diabetes, duration of disease , mean fasting and postprandial blood sugar, complications (eye, kidneys, peripheral nerves, foot, cardiovascular, cerebrovascular), and timing of complications with regard to duration of disease were collected.
Results: The study population included 392 patients (205 males and 186 females), 300 patients had type 2 and 92 had type 1 diabetes. The mean age at diagnosis was 20.412.8 years for type 1 and 47.510.4 years for type 2 patients. 95% of patients developed at least one chronic complication during the follow-up period. The incidence rates of eye , renal, and peripheral nerve complications were 51.5, 44.7, and 68.8 percent respectively. Diabetic foot problems occurred in 16.8 percent of cases and it led to amputation in 8.4 percent (33 cases) of patients. The incidence rates of cardiovascular and cerebrovascular complications were 49.7 and 15.3 percent respectively. The development of eye, renal, and peripheral nerve complications was related to blood sugar control.
Conclusion: Our diabetic patients developed chronic complications early and at a higher than expected rates. Future studies and more emphasis on prevention methods are recommended.

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Background: Due to homeostatic and regulatory potentials of nitric oxide (NO) in vascular physiology, regulatory systems that determine NO bio-synthesis and bioavailability have been the subject of extensive research in molecular medicine. In the field of vascular system pathophysiology, endothelial nitric oxide synthase (eNOS) which is the major producer and regulator of NO in vascular tissues has received the most attention. Impairment of NO bioavailability (NO quenching) is a common feature in poorly controlled diabetics due to increased catabolism and decreased production of NO. Such impairment in severe forms could end to vasodilation breakdown in peripheral tissues (mainly in skeletal muscles) and defective regional blood flow, that in turn disturb insulin-dependent glucose uptake ensuing insulin resistance state.
Methods: The phenotypic impact of an eNOS gene polymorphism at position 786*C/T (that its functionality has been revealed already) on genetic propensity to diabetic retinopathy is evaluated in a British-Caucasian population with type 1 diabetes (T1DM).
Results: In contrast to genotypes, there was a significant difference in distribution of allele frequencies between T1DM patients (n= 249) and healthy controls (n= 104) (p= 0/036), that may imply eNOS and/or NO involvement in development of T1DM. Most notably a significant difference also was evident in allele frequency between retinopaths (n= 134) and healthy controls (p= 0/02). No significant difference was detected when the genotype/allele frequencies were compared between retinopaths (n= 134) and non-retinopaths diabetics (n= 115) (p=NS).
Conclusion: Our data is compatible with previous studies which demonstrated that allele C of eNOS 786*C/T polymorphism is associated with increased HbA1c levels. By emphasizing the phenotypic and prognostic value of the abovementioned polymorphism, our data calls for further investigations to find out whether this polymorphism can be employed as a genetic marker in clinical medicine to recognize high-risk diabetics at the time of diabetes onset/diagnosis.

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Background: VEGF is newly discovered growth factor that has diverse biologic properties. The bottom-line of these activities is conduction and orchestration of a series of reactions that are taking place at microvasculature of different tissues/organs. Among the growth factors, cytokines and other mediators that reflect meaningful alteration in their local/systemic level, VEGF is the distinct player which can explain by its own all hemodynamic and architectural manifestations present in diabetic retinopathy (DR). The present study was conducted to pursue the role of a candidate gene structure variation, VEGF gene polymorphisms, in genetic susceptibility/resistance to development of DR through a cross sectional case-control study.
Methods: The frequency of four SNPs in VEGF gene at positions –7*C/T, –1001*G/C, –1154*G/A and –2578*C/A has been traced among 248 type 1 diabetic subjects (135 DR+, 113 DR−) along with 95 healthy controls. The populations had "British-Caucasian" background and ARMS-PCR technique was employed for DNA genotyping.
Results: Comparing the polymorphic variants' frequency at both allelic and genotypic levels among different groups/subgroups, significant difference was noticeable for –7*C/T polymorphism between diabetic patients with vs. without DR, while T allele conferred protective effect (p=0.002 OR=1.98).
Conclusion: Contemplating that up-regulation/over-expression of VEGF (local/systemic) as a common pre-requisite for DR development, our hypothesis was that whether the VEGF gene structural variations is correlated with the magnitude of VEGF expression in response to different stimuli present in diabetic context, namely hypoxia and hyperglycemia. Our data indicate that among the examined polymorphisms of VEGF gene, only SNP at position –7*C/T harbored significant difference between DR+ vs. DR− cases, proposing phenotypic impact for that SNP illustrating by evolvement/impediment of DR. However, reminding the insubstantial role of genetic issues in development of DR relative to DN or DNU, replicating current hypothesis by providing larger sample size and also employing more polymorphic markers could shed more light on the subject of present study.

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Background: Retinopathy is one of the microvascular complications of diabetes which is strongly related to the glycemic control and duration of the disease. According to results of other studies, the prevalence of retinopathy has been reported 5-30% in newly diagnosed patients whit type 2 diabetes (T2DM). The aim of this study was to determine the prevalence of idabeteic retinopathy among newly diagnosed T2DM patients in Isfahan, Iran.
Methods: From july 2001 to March 2004, 710 newly diagnosed patients with T2DM were recruited in this study. Patients with duration of diabetes less than 1 year were considered as newly diagnosed ones. Along with physical examination and laboratory measurment for FBS, HbA1c, lipid profile, urea, Creatinin, and 24 houre urin examniation for albumin, retinoscopy was performed by an experienced ophttalmologist.
Results: In this study, 286 men and 424 women were investigated. The mean age of patients at presentation and the mean duration time of diabetes were 48.8 ±9.8 years (range 31-72years) and 8.6±5.4 months respectively. The prevalence of retinopathy was 9 % (9/8% in males and 8.5% in females). Logistic regression analysis revealed that BMI, diastolic blood pressure and 24 hour urine albumin, were independent risk factors for developing retinopathy.
Conclusion: Nevertheless of relatively moderate prevalence of diabetic retinopathy in our study as compared with other studies, it is necessary to perform retinal examination in newly diagnosed T2DM patients in order to prevent the sight-threatening outcomes of diabetic retinopathy.

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Background: The alteration of IGF-I systemic level in diabetes is typically characterized by depletion of free IGF-I plasma level and its decreased bioavailability. With regard to protective and advantageous effects of IGF-I on tissue healing and cellular regeneration such depletion could facilitate or accelerate tissue damages and complications.  By contrast, the local concentration of IGF-I is reportedly increased in particular tissues during some occasions, which has also clinical implications as IGF-I could function in an autocrine and paracrine manner.

The present study was conducted to assess that whether the differential outcome of diabetic subjects relative to diabetic retinopathy (DR) is linked to some extent to the structural variations of IGF-I gene.

Methods: Two polymorphisms of the IGF-I gene at positions -383*C/T and -1089*C/T were employed for genotyping analysis by ARMS-PCR assay and the data of genotype/allele distribution was compared between two subgroups of 248 British Caucasian type 1 diabetic subjects, 135 cases with DR and 113 controls (DR^-).

Results: The distribution of these polymorphisms did not associate significantly with presence or absence of DR (P≥ 0.05).

Conclusion: Since the involvement of IGF-I in development of DR is fairly rational, our results firstly may reflect some reservations about the functionality of the employed polymorphic markers and secondly may indicate that all regulators of IGF-I functionality or its local concentration level including IGFBPs and IGFRs should be taken into account, so their genes could be the subject of new study to accomplish current investigation.