فهرست مطالب

International Journal of Endocrinology and Metabolism
Volume:2 Issue: 1, Mar 2004

  • تاریخ انتشار: 1383/07/20
  • تعداد عناوین: 8
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  • Page 1
    Iodine of maternal origin is required for brain development of the progeny during fetal and early postnatal life. Therefore, the iodine requirements of the mother are increasedduring pregnancy and lactation. This paper reevaluates the iodine requirements duringpregnancy, lactation and the neonatal period and formulates original proposals for the median concentrations of urinary iodine indicating optimal iodine nutrition during these three critical periods of life. Based on an extensive and critical review of the literature on thyroid physiopathology during the perinatal period, the following proposals are made: the iodine requirements are 250-300 #g/day during pregnancy, 225-350 #g/day during lactation and 90 #g/day during the neonatal period. The median urinary iodine indicating optimal iodine nutrition during these three periods should be in the range 150-230 #g/L. These figures are higher than those recommended so far by international agencies.
  • Page 13
    Diabetes is a common endocrine disease and its complications are major stimuli for the enhancment of efforts towards its control. At present, glycosylated hemoglobin (HbA1c) is used for long term control of glucose levels in diabetic patients, but due to lack of availability of a standard control method, recent findings suggest that insulin-like growth factor-I (IGF-I) may be used as a biomarker for glycaemic control. The aim of this study was to examine the correlation between IGF-I and glycaemic control measured as fasting plasma glucose (FPG) and HbA1c in Type 1 diabetes.
    Materials And Methods
    We designed a crosssectional case-control study with systematic random sampling. The study included 26 newly diagnosed patients with Type 1 diabetes (15 male and 11 female; mean age 23.7±9.1 years) and 26 healthy controls (9 male and 17 female; mean age 24.1±4.4 years). The concentrations of FPG, IGF-I, HbA1c and IGF-binding protein-3 (IGFBP-3) were measured in both groups. FPG was measured by the enzymatic glucose oxidase method and the colorimetric method was used tomeasure HbA1c. Determination of serum IGF-I and IGFBP-3 total levels was carried out using immunoassay. P<0.05 was considered as statistically significant.
    Results
    The mean value of IGF-I concentration in Type 1 diabetics was significantly lower than in controls (p<0.05). No correlation was found between IGF-I and HbA1c in the patients.
    Conclusion
    Our data shows that total IGF-I levels are low in patients with Type 1 diabetes. No relationship was found between IGF-I and glycaemic control. However, more detailed intensive studies to further investigate this relationship are recommended.
  • Page 19
    he purpose of this study was to investigate the effect of the volume of consumed water on the sweating response and plasma levels of arginine vasopressin, epinephrine and norepinephrine in the first few minutes of drinking.
    Materials And Methods
    After 4 hours water deprivation, six healthy male medical students were exposed to heat and performed mild exercise under an ambient temperature (2 hours, 38-40°C, relative humidity<30%). Subjects were dehydrated by sweating. They were then allowed to drink water with volumes of 1, 3, and 5 ml/kg of body weight using three separate protocols. Sweat rate was measured by amountof sweat collected from the forehead area in grams during 3 minute periods before and after drinking. Blood samples were drawn before heat exposure, before drinking and then every 3 minutes up to the 15th minute after drinking.
    Results
    Dehydration increased mean serum sodium (p<0.001). Sweating increased markedly just after the onset of drinking (p<0.01) and was greater when consumed water was 5ml/kg of body weight. The more the water volume consumed,the greater was the reduction in plasma arginine vasopressin 3 minutes after drinking.The reverse was true for plasma norepinephrine (p<0.01), whereas plasma epinephrine was essentially unchanged by drinking.
    Conclusion
    These data suggest that oropharyngeal sensors that interfere with the activation of sweating response can also manipulate it by consumed water volume. Moreover, the amount of water received affected plasma arginine vasopressin and norepinephrine but not plasma epinephrine which suggests a drinking stimulated neural mechanism.
  • Page 29
    Isoflavones are a group of phytoestrogens found mainly in soy bean and its products.Their actions on various tissues have motivated researchers to assess the possible related mechanisms and functions. The main objective of this study is to determine the metaboliceffects of purified alcohol-extracted soy protein isoflavones (SPI) on serum lipoproteinsand hormones of mild to moderate hypercholesterolemic male subjects. The effects of SPI on this type of patients and on the serum hormone levels have not been evaluated previously.
    Materials And Methods
    30 male volunteers were randomly divided into two groups in a doubleblind parallel randomized placebo-controlled trial (n=15). Group 1 received 50mg purified alcohol- extracted soy isoflavones solution and group 2 received placebo in a similarly colored solution for an 8-week period. Both groups were matched for age, duration of illness, medications, and diet. Data on other variables of each subject i.e. body mass index, smoking habits, blood pressure, and past medical history were also collected.
    Results
    LDL-, VLDL-, and HDL-cholesterol, Tg and thyroxine, triiodothyronine, FSH, testosterone and fasting blood sugar levels did not change significantly compared to their baseline levels. Total cholesterol decreased by 10 percent, (p=0.055). TSH levels in SPI group showed a significant rise after intervention (p<0.05), remaining, however,within normal range.
    Conclusion
    These results indicate that alcoholextracted SPI without soy protein does not affect serum lipid profiles and hormones in hypercholesterolemic men. More trials with larger number of subjects conducted over a longer period of study are needed to confirm these findings.
  • Page 35
    Thyrotoxic periodic paralysis (TPP) is a fairly common accompaniment of thyrotoxicosisin Orientals. The disorder is a rare complication of thyrotoxicosis in the United States and Europe. There is no published study on the prevalence of hypokalemic periodic paralysis in thyrotoxic Iranian patients. In order to obtain a fairly good estimate, the prevalence of TPP among thyrotoxic patients from the northwestern part of Iran (east Azerbaijan province) was investigated.
    Materials And Methods
    All new cases of thyrotoxicosis attending the endocrine clinics of Tabriz University of medical sciences were questioned specifically on the occurrence of periodic paralytic attacks. Only patients who had experienced one or more attacks of flaccid paralysis of extremities lasting from a few hours to few daysand followed by complete spontaneous or inhospital recovery were included. Thirty-nine patients were evaluated during paralytic episodes. In 14 cases, diagnosis was based on typical and compatible history given by thyrotoxic patients.
    Results
    During a 10-year period between 1989 and 1999 a total of 5463 patients were seen with thyrotoxicosis of various etiologies. Of these patients, 4451 (81.5%) were female and 1012 (18.5%) were males. Among this thyrotoxic population,there were 53 proved cases of TPP (4 females and 49 males). All patients were Iranian from the northwestern part of the country; the prevalence of TPP among male patients was 4.8% and among thyrotoxic females 0.08%, with an overall prevalence of 0.97%
    Conclusion
    This prevalence rate is one half the rates reported from Japan and China and approximately 10 times the rate reported from the United States. It is concluded that TPP is a relatively common complication of thyrotoxicosis in Azari Iranians. Physicians should be cognizant of this condition to ensure early diagnosis and treatment of a potentially life-threatening but remediable disorder.
  • Page 41
    atients with chronic renal failure have abnormal thyroid function and higher levels of serum aluminum. In recent years, the toxicity of Al in human and animals has been a matter of concern. In this study the effect of high aluminum intake in the diet has been investigated in rats.
    Materials And Methods
    Aluminum (1620 mg/kg of the diet as aluminum chloride) was added to the diet of Wistar rats for 40 days. At the end of this period serum aluminum, T4 and TSH concentrations were measured. Aluminum was determinedby atomic absorption spectrometry and the hormones were assayed using commerciallyavailable kits.
    Results
    Serum aluminum concentration of the test rats (6.3±.1 μg/L) was not significantly different from controls (6.6±.4 μg/L). Serum T3 concentration in animals consuming a diet with high aluminum content (138±8 ng/dL) was not significantly different from the control animals (146±7 ng/dL). Serum T3, T4 concentration of thetest animals (3.0±0.3 μg/dL) was significantly lower than control animals (4.7±0.5 μg/dL,p<0.05). Thyrotropin concentrations were not significantly different.
    Conclusion
    The results of this study indicate that high aluminum intake in rats can disturb thyroid function and possible adverse effect(s) of the element need to be considered and fully investigated in subjects in close contact with high amounts
  • Page 47
    Anti-thyroid drugs, methimazole, carbimazole and propylthiouracil are commonly prescribed for the treatment of hyperthyroidism due to Graves’ disease. We present here the report of a Caucasian patient with Graves’ disease who developed ANCA positive propylthiouracil induced vasculitis. The episode was characterised by a vasculitic skin rash associated with polyarthralgia but no renal involvement. While carbimazole/ methimazole has a lower incidence of reported ANCA positive side effects than PTU, the use of the latter in pregnancy may still be considered as reasonable because the immunosuppressionof pregnancy may prevent the appearance of immune problems.
  • Page 51
    Diabetes today is a worldwide problem. The purpose of this study is to assess, in developed and developing countries, the productivity of research on diabetes and to evaluate the gap between the burden of diabetes and research conducted on diabetes.
    Materials And Methods
    An extensive search in PubMed database for diabetes publications (all publication types, all languages) using diabetes as the MeSH term was carried out to ascertain the proportion of diabetes-related publications from countries of different regional (according to WHO regions) and economic (according to World Bank) classifications in 1992, 1997 and 2002. We excluded all publications without the name of a country as affiliation, as we did for publications from the U.S. following which the quota of international publications of countries was calculated. All information related to thedistribution of the global burden of diabetes was extracted from the literature available.
    Results
    Worldwide, the overall growth rate of publications on diabetes during 1992-2002 was 66.3% with a higher rate during 1997-2002, as compared to that of 1992-1997 period (31% vs. 27%). The highest growth rate was found in the South and East Asia region (226%), and the second highest in the Eastern-Mediterranean region(138%). However, the quota of the international publications of these two regions reached 3.9% and 2.5% in 2002, respectively. Developed market economies (except for U.S.) contributed 85.4% (1668) of publications in 1992, 83.0% (2276) in 1997 and 76.7% (2806) in 2002. Contributions of developing countries increased from 12.3%(242) in 1992 to 13.8% (380) in 1997 and 19.8% (726) in 2002. Also, contributions of the developing eastern European countries rose from 2.2% (43) in 1992 to 3.1% (85) and 3.4% (125) in 1997 and 2002, respectively.
    Conclusion
    Despite the fast growth in prevalence of diabetes in developing countries, the quota of international publications on diabetes from developed countries is definitely higher than that of developing countries. Facilitating increases in financial resources and the indexing of national journals in these countries may serve to improve their quota.