78 research outputs found
Extreme learning machine-based model for solubility estimation of hydrocarbon gases in electrolyte solutions
Calculating hydrocarbon components solubility of natural gases is known as one of the important issues for operational works in petroleum and chemical engineering. In this work, a novel solubility estimation tool has been proposed for hydrocarbon gases—including methane, ethane, propane, and butane—in aqueous electrolyte solutions based on extreme learning machine (ELM) algorithm. Comparing the ELM outputs with a comprehensive real databank which has 1175 solubility points yielded R-squared values of 0.985 and 0.987 for training and testing phases respectively. Furthermore, the visual comparison of estimated and actual hydrocarbon solubility led to confirm the ability of proposed solubility model. Additionally, sensitivity analysis has been employed on the input variables of model to identify their impacts on hydrocarbon solubility. Such a comprehensive and reliable study can help engineers and scientists to successfully determine the important thermodynamic properties, which are key factors in optimizing and designing different industrial units such as refineries and petrochemical plants
The Association of Chlamydia pneumonia and Helicobacter pylori IgG Seropositivity With Omentin-1, Visfatin and Adiponectin Levels in Postmenopausal Women.
Abstract
Some adipocytokines are cardioprotective or pro-inflammatory for cardiovascular system. Chronic infection with Chlamydia pneumoniae and Helicobacter pylori has been also considered as novel risk factors for atherosclerosis. The main aim of the current population-based study is to investigate the potential link between circulating adipocytokines and Chlamydia pneumoniae or Helicobacter pylori IgG seropositivities. A total of 250 healthy postmenopausal women who participated in a prospective cohort study were evaluated for IgG antibodies directed against C.pneumoniae and H. pylori. Omentin-1, visfatin, adiponectin, and high sensitivity C-reactive protein were measured by highly specific enzyme-linked immunosorbent assay methods. The prevalence of IgG antibodies against C. pneumoniae and H. pylori among the studied population was 20.4% (51 women) and 57.2% (143 women), respectively. There were no significant differences in adipocytokine levels between H. pylori IgG seropositive and H. pylori seronegative subjects. Similar results for visfatin and omentin-1 were found when C. pneumoniae IgG seropositive were compared with C. pneumoniae IgG seronegative subjects. However, in general linear model adjusted for age, body mass index and hs-CRP levels revealed significant difference between C. pneumoniae seropositive and C. pneumoniae seronegative subjects for circulating adiponectin. In conclusion, Chlamydia pneumoniae IgG seropositivity was associated with higher adiponectin levels in postmenopausal women. The elucidation of interaction mechanism of Chlamydia pneumoniae and a cardioprotective adipocytokine (adiponectin) will be useful in future therapeutic strategies
Relationship among dietary estimates of net endogenous acid production, bone mineral density and biochemical markers of bone turnover in an Iranian general population
Chronic, low-grade metabolic acidosis due toWestern diets may be a risk factor for osteoporosis. The severity
can be determined in part by net endogenous acid production (NEAP). In a population-based study, a total of
1028 healthy men and women aged 20–72 years were evaluated for dietary intakes and NEAP estimates with
a validated food frequency questionnaire. Dual-energy X-ray absorptiometry (DXA) was used to determine
BMD of the lumbar spine (L2–L4), distal third of radius, and proximal femur. Serum CrossLaps, degradation
products of the C-terminal telopeptides of type I collagen, and osteocalcin were measured by highly specific
ELISA methods. Lower estimates of energy-adjusted rates of NEAP were associated with greater femoral neck
BMD (p=0.01) in premenopausal women and with greater BMDs at the distal radius (p=0.001) and lumbar
spine (p=0.04) in postmenopausal women. Compared with women in the highest quartile of the estimates
of the energy-adjusted rates of NEAP, pre- and postmenopausal women in the lowest quartile had
significantly greater means of osteocalcin [9.12 (SD±1.62) vs. 5.24 (SD±1.41) ng/ml, p=0.02 and 11.74
(SD±1.69) vs. 7.79 (SD±2.63) ng/ml, p=0.002, respectively]. Analysis by quartiles of the estimates of
energy-adjusted rates of NEAP did not reveal a relationship between BMD and bone turnover markers in
men. In conclusion, we found that a high energy-adjusted rate of NEAP was associated with a significantly
lower BMD in women but not in men and the energy-adjusted rate of NEAP had a negative relationship with
bone formation
99mTc-MIBI Lung Scintigraphy in the Assessment of Pulmonary Involvement in Interstitial Lung Disease and Its Comparison With Pulmonary Function Tests and High-Resolution Computed Tomography
Abstract: The differentiation of active inflammatory processes from
an inactive form of the disease is of great value in the management of
interstitial lung disease (ILD). The aim of this investigation was to
assess the efficacy of 99mTc-methoxy-isobutyl-isonitrile (99mTc-
MIBI) scans in distinguishing the severity of the disease compared
to radiological and clinical parameters.
In total, 19 known cases of ILD were included in this study and were
followed up for 1 year. Five patients without lung disease were
considered as the control group. The patients underwent pulmonary
function tests (PFTs) and high-resolution computed tomography scans,
followed by 99mTc-MIBI scanning. The 99mTc-MIBI scans were
analyzed either qualitatively (subjectively) or semiquantitatively.
All 19 ILD patients demonstrated a strong increase in 99mTc-MIBI
uptake in the lungs compared to the control group. The 99mTc-MIBI
scan scores were higher in the patient group in both the early phase
(0.24[0.19–0.31] vs 0.11[0.10–0.15], P<0.05) and the delayed phase
(0.15[0.09–0.27] vs 0.04[0.01–0.09], P<0.05) compared with the
control group. A positive correlation was detected between the
99mTc-MIBI scan and the high-resolution computed tomography
(HRCT) scores (Spearman’s correlation coefficient ¼ 0.65, P<0.02)
in the early phase but not in the delayed phase in patients (P>0.14). The
99mTc-MIBI scan scores were not significantly correlated with the PFT
findings (P>0.05). In total, 5 patients died and 14 patients were still
alive over the 1-year follow-up period. There was also a significant
difference between the uptake intensity of 99mTc-MIBI and the
outcome in the early phase (dead: 0.32[0.29–0.43] vs alive:
0.21[0.18–0.24], P<0.05) and delayed phase (dead: 0.27[0.22–0.28]
vs alive: 0.10[0.07–0.19], P<0.05).
The washout rate was �40 min starting from 20 min up to 60 min
and this rate was significantly different in our 2 study groups (ILD:
46.61[15.61–50.39] vs NL: 70.91[27.09–116.36], P¼0.04).
The present study demonstrated that 99mTc-MIBI lung scans might
distinguish the severity of pulmonary involvement in early views, which
were well correlated with HRCT findings. These results also revealed
that 99mTc-MIBI lung scans might be used as a complement to other
diagnostic and clinical examinations in terms of functional information
in ILD; however, further investigations are strongly require
Association of serum uric acid with high-sensitivity C-reactive protein in postmenopausal women.
OBJECTIVES:
To explore the independent correlation between serum uric acid and low-grade inflammation (measured by high-sensitivity C-reactive protein, hs-CRP) in postmenopausal women.
METHODS:
A total of 378 healthy Iranian postmenopausal women were randomly selected in a population-based study. Circulating hs-CRP levels were measured by highly specific enzyme-linked immunosorbent assay method and an enzymatic calorimetric method was used to measure serum levels of uric acid. Pearson correlation coefficient, multiple linear regression and logistic regression models were used to analyze the association between uric acid and hs-CRP levels.
RESULTS:
A statistically significant correlation was seen between serum levels of uric acid and log-transformed circulating hs-CRP (r = 0.25, p < 0.001). After adjustment for age and cardiovascular risk factors (according to NCEP ATP III criteria), circulating hs-CRP levels were significantly associated with serum uric acid levels (β = 0.20, p < 0.001). After adjustment for age and cardiovascular risk factors, hs-CRP levels ≥3 mg/l were significantly associated with higher uric acid levels (odds ratio =1.52, 95% confidence interval 1.18-1.96).
CONCLUSION:
Higher serum uric acid levels were positively and independently associated with circulating hs-CRP in healthy postmenopausal women.
KEYWORDS:
C-reactive protein; Uric acid; inflammation; postmenopaus
HypertensionriskandconventionalriskfactorsinaprospectivecohortstudyinIran:ThePersianGulfHealthyHeartStudy
Hypertensionriskandconventionalriskfactorsinaprospectivecohort studyinIran: ThePersianGulfHealthyHeartStudy
Association of Pathogen Burden and Hypertension: The Persian Gulf Healthy Heart Study
background
Chronic infection with cytomegalovirus (CMV), Chlamydia pneumoniae,
herpes simplex virus 1 (HSV-1), and Helicobacter pylori may contribute
to essential hypertension. However, the evidence now available does
not clarify whether the aggregate number of pathogens (pathogen
burden) may be associated with hypertension.
methods
Sera from 1,754 men and women aged ≥25 years were analyzed for
immunoglobulin G antibodies to C. pneumoniae, HSV-1, H. pylori,
and CMV using enzyme-linked immunosorbent assay. The aggregate
number of seropositives to the studied viral and bacterial agents was
defined as pathogen burden. Hypertension was defined according to
World Health Organization criteria.
results
A total of 459 (26.3%) of the subjects had hypertension. In the hypertensive
group, 4.2% had 0 or 1 pathogens present, 20.6% had 2, 43.2%
had 3, and 32.1% had 4; in the normotensive group, 7.9% had 0 or 1,
28.4% had 2, 42.7% had 3, and 21.0% had 4. Of the 4 studied pathogens,
H. pylori seropositivity showed a significant independent association
with hypertension (odds ratio (OR) =1.37; 95% confidence interval
(CI) =1.05–1.79; P = 0.02). In multiple logistic regression analyses, the
pathogen burden did not show a significant independent association
with hypertension. Coinfection with H. pylori and C. pneumoniae
was significantly associated with hypertension compared with double
seronegativity after adjustment for age, sex, chronic low-grade inflammation,
and cardiovascular risk factors (OR = 1.68; 95% CI = 1.14–2.47;
PÂ =Â 0.008].
conclusions
The pathogen burden was not associated with hypertension. However,
coinfection with C. pneumoniae and H. pylori showed a significant association
with essential hypertension, independent of cardiovascular risk
factors and chronic low-grade inflammation.
Keywords: blood pressure; Chlamydia pneumoniae; cytomegalovirus;
Helicobacter pylori; herpes simplex virus; hypertension; pathogen
Bushehr Elderly Health (BEH) Programme, phase I (cardiovascular system)
Purpose: The main objective of the Bushehr Elderly
Health Programme, in its first phase, is to investigate
the prevalence of cardiovascular risk factors and their
association with major adverse cardiovascular events.
Participants: Between March 2013 and October
2014, a total of 3000 men and women aged
≥60 years, residing in Bushehr, Iran, participated in
this prospective cohort study ( participation
rate=90.2%).
Findings to date: Baseline data on risk factors,
including demographic and socioeconomic status,
smoking and medical history, were collected through a
modified WHO MONICA questionnaire. Vital signs and
anthropometric measures, including systolic and
diastolic blood pressure, weight, height, and waist and
hip circumference, were also measured. 12-lead
electrocardiography and echocardiography were
conducted on all participants, and total of 10 cc
venous blood was taken, and sera was separated and
stored at –80°C for possible future use. Preliminary
data analyses showed a noticeably higher prevalence of
risk factors among older women compared to that in
men.
Future plans: Risk factor assessments will be
repeated every 5 years, and the participants will be
followed during the study to measure the occurrence
of major adverse cardiac events. Moreover, the second
phase, which includes investigation of bone health and
cognition in the elderly, was started in September
2015. Data are available at the Persian Gulf Biomedical
Research Institute, Bushehr University of Medical
Sciences, Bushehr, Iran, for any collaboratio
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