Development of a Modified Friedewald's Formula to Calculate Low-Density Lipoprotein in an Iranian Population.

Background: Elevated low-density lipoprotein cholesterol (LDL-C) is a significant risk factor for cardiovascular diseases. LDL-C can be directly measured using various methods, but this requires expensive equipment. Currently, clinical laboratories estimate LDL-C based on Friedewald's formula (FF). We aimed to develop a modified formula based on directly measured LDL-C (D-LDL-C) values in a large population in Southern Iran and compare the results with various other estimation formulas. Methods: The participants of this cross-sectional study were adults aged >18 years living in Southern Iran. Blood samples from 15,200 individuals were collected, and the measured lipid parameters were randomly divided into training (n=10,184) and validation (n=5,016) datasets. A new formula was developed using a linear regression model, and its accuracy was validated. Pearson's correlation and Cohen's kappa were used to determin the relationship between D-LDL-C and calculated LDL-C (C-LDL-C). Results: The developed formula for the estimation of LDL-C was 0.857 total cholesterol (TC)-0.915 high-density lipoprotein cholesterol (HDL-C)-0.115 triglycerides (TG). Based on our proposed formula, for TG<150 and TG≥150 mg/dL, there was a significant correlation between mean values of D-LDL-C and C-LDL-C (r=0.985 and r=0.974, respectively). Compared to other formulas, C-LDL-C obtained from the proposed formula had the highest correlation with D-LDL-C. The agreement between D-LDL-C and C-LDL-C for TC<200, 200-239, and ≥240 mg/dL was 80.8%, 63.2%, and 67.4%, respectively, indicating a higher level of agreement than other formulas. Conclusion: The new formula appears to be more accurate than FF when applied to the population of Southern Iran.

A high dose of estrogen can improve renal ischemia-reperfusion-induced pulmonary injury in ovariectomized female rats.

Renal ischemia-reperfusion injury (RIRI) as a pathological process induces remote organ injury such as lung complications and it is regulated in a hormone-dependent manner. This study investigates the effect of estrogen on RIR-induced pulmonary injury in ovariectomized (OV) rats. A total of 60 female Wistar rats were divided into six groups: (i) intact sham, (ii) OV sham, (iii) OV sham + estradiol valerate (E), (iv) intact ischemia, (v) OV ischemia, and (vi) OV ischemia + E. Bilateral ischemia was performed for 45 min in all groups except sham. Before the ischemia, OV groups received an intramuscular (i.m.) injection of E. After reperfusion, blood samples were collected for serum analysis and kidney and lung tissue were separated for pathological experiment and malondialdehyde (MDA) and nitrite measurement. The left lung was weighed to measure pulmonary edema. Estrogen deficiency caused a greater increase in blood urea nitrogen and creatinine levels during IRI. Ischemia reduced nitrite of serum and lung tissue. The increased level of MDA during ischemia, returned to normal levels via estrogen injection. The severity of renal and lung damage in ischemic groups increased significantly, and estrogen improved this injury. Estrogen as an antioxidant agent can reduce oxidative stress and may improve renal function and ameliorating lung damage caused by RIR.

Immune deviation in recurrent vulvovaginal candidiasis: correlation with iron deficiency anemia.

BACKGROUND: Iron Deficiency Anemia (IDA) has been controversially linked to IL-4 production in previous studies. A predominant Th1 response leads to resistance against recurrent vulvovaginal candidiasis (RVVC), whereas a Th2 response exacerbates the disease. OBJECTIVE: To investigate the possible effect of iron deficiency on the host's susceptibility to RVVC as a result of the Th1/Th2 cytokine polarization. METHODS: We conducted a case-control study of 92 women in 4 groups based on strict inclusion and exclusion criteria: RVVC+IDA+ group consisted of 23 women with RVVC and IDA; RVVC+ IDA- group consisted of 23 women with RVVC without IDA; RVVC-IDA+ group consisted of 23 women without RVVC and with IDA and RVVC- IDA- group consisted of 23 healthy women. The iron parameters and key cytokines (IFN-γ, IL-10, IL-12, IL-4) were measured in blood samples. RESULTS: Comparison of IL-4 production between RVVC+ IDA+ (12.2 ± 1.3 pg/ml) and RVVC+ IDA- (2.4 ± 4.0 pg/ml) groups (p=0.044), between RVVC- IDA+ (14.6 ± 1.7 pg/ml) and RVVC- IDA- (1.28 ± 3.6 pg/ml) groups (p=0.006), between RVVC- IDA+ (14.6 ± 1.7 pg/ml) and RVVC+ IDA-) 2.4 ± 4.0 pg/ml) groups (p=0.009) and also between RVVC+ IDA+ and RVVC- IDA- (1.28 ± 3.6 pg/ml) groups (p=0.03) showed significant differences. We found a significant positive correlation between IL-4 and total iron binding capacity (TIBC, p=0.046) and between serum IL-10 and Hb levels (p=0.041) in the RVVC+ IDA- group. There was also a significant negative correlation between serum IL-4 and levels of serum iron (SI, p=0.041) in the RVVC- IDA- group. CONCLUSION: It seems that IDA determines the balance between and the intensity of Th1 and Th2 arms of the immune response and leads to a deviation toward Th2 response which could contribute to recurrence of candidiasis.

Prevalence of HBc-Ab among HBs-Ag negative healthy blood donors in south of Iran.

BACKGROUND: The risk of infection with transfusion-transmitted viruses, such as Hepatitis B virus (HBV), has been reduced markedly. However, a zero-risk blood supply remains a popular goal. Anti-hepatitis B core antigen (anti-HBc) is considered to be an effective marker for occult HBV infection, and it has served a significant role in improving blood safety. The purpose of this study was to determine the seroprevalence of anti-HBc antibodies among blood donors. METHODS: During a period of six months in 2012, 1000 blood donors in Bandar Abbas were investigated for the presence of HBV infection markers. We used ELISA for the detection of HBsAg and chemiluminescence for the detection of HBsAb and anti-HBc antibodies. RESULTS: The prevalence of positive anti-HBc among the 1000 donors was 8.3%. Almost 2.3% of the donors were reactive for anti-HBc and negative for HBsAg. CONCLUSIONS: The study showed that more than 2% of healthy blood donors in Bandar Abbas already have been exposed to HBV, although their HBsAg tests were negative. We suggest screening for anti-HBc to improve the safety of the blood supply.