Bat guano and historical evidence of climate changes in the west of Iran during the Late Holocene (Meghalayan Stage)

An 86 cm thick sequence of bat guano layers in the Kolatarika Cave in Kurdistan province in the west of Iran was analysed. The sequence was radiocarbon dated and covers an age of approximately 4060 years. The results of geochemical data, statistical studies, along with the investigation, analysis and explanation of historical sources indicate the presence of warm and dry climate conditions between ca 2100 BC and 800 CE. These were contemporaneous with the occurrence of periods of drought and famine during the Achaemenid and Sassanid empires, and might have been was one of the causes of their ‘collapse. The existence of humid climate conditions between 800 and 1450 AD was contemporaneous with the period of Medieval Climate Anomaly and the historically documented prosperity of farms and agriculture during the Seljuk dynasties, the Samanids, and the rise of rainfall and river floods during the period of the Abbasid caliphate. The presence of cold and humid climate conditions between ca 1600 and 1750 AD was consistent with the so-called Little Ice Age and the Maunder Minimum. After this period, the climate of this area changed to warm and dry which was contemporaneous with the occurrence of famine and subsequent droughts of the late Safavid and Qajar dynasties in Iran.Key words: palaeoclimate, geochemistry, Little Ice Age, Medieval Climate Anomaly, Kolatarika Cave, Iran.Poznoholocenske podnebne spremembe v zahodnem Iranu: analize netopirskega gvana in zgodovinskih dokumentovV članku predstavimo analize 86 centimetrov debelega zaporedja plasti netopirskega gvana v jami Kolatarika v provinci Kurdistan, Zahodni Iran. Radiometrično ugotovljen starostni razpon gvana obsega zadnjih 4060 let. Statistična obravnava geokemičnih analiz gvana in raziskava zgodovinskih virov kažeta na toplo in suho podnebje v obdobju 2100 pr. n. št. in 800 n. št. To sovpada s sušami in lakoto v času ahamenidskega in sasanidskega cesarstva, kar je bil najverjetneje tudi vzrok njunega propada. Analize gvana kažejo na vlažno podnebje med 800 n. št. in 1450 n. št., kar ustreza srednjeveški podnebni anomaliji in obdobju razvoja kmetijstva in blaginje v času dinastij Seldžukov in Samanidov. Vlažno podnebje s padavinami je povzročilo tudi poplavljanje rek v času abasidskega kalifata. Hladno in vlažno obdobje med letoma 1600 in 1700 sovpada z malo ledeno dobo oziroma Maunderjevim minimumom. Po tem obdobju podnebje postane toplejše in bolj suho, kar spet sovpada z lakoto in sušami v poznem obdobju safavidske in kadžarske dinastije v Iranu.Ključne besede: paleoklima, geokemija, mala ledena doba, srednjeveška podnebna anomalija, jama Kolatarika, Iran.

Assessment of pyridoxine and folate intake in migraine patients

Background: Migraine is a highly prevalent disorder worldwide. It affects 10–20% of the population during their lifetime. Recent studies have indicated that supplementation with folate and pyridoxine improves migraine symptoms. This study was undertaken to evaluate dietary intake of folate and pyridoxine in migraine patients and assessed their association with the frequency of migraine attacks. Materials and Methods: This is a case–control study performed on 124 migraine patients and 130 non-migraine subjects. Individuals' common dietary intake was determined by using a valid semi-quantitative 168-item food frequency questionnaire (FFQ). Data had been analyzed using independent t-test using SPSS software (version 18). Results: In this study, we found that migraine patients had lower intake of dietary folate compared with control group, but energy and pyridoxine intake were not different between the two groups. Further analysis among men and women revealed no statistically significant changes in these relationships. In addition, we found no significant association between dietary intake of pyridoxine and folate with the frequency of migraine attacks. Conclusion: Migraine patients had lower dietary intake of folate, compared with non-migraine group subjects. There was no significant association between folate and pyridoxine intake with the frequency of migraine attacks. Further studies are needed to confirm our findings

The association between abdominal obesity and characteristics of migraine attacks in Iranian adults

Background: Migraine is a primary headache disorder that affects the neurovascular system. Recent studies have shown that migraine patients with general obesity have higher characteristics of migraine attacks compared with normal weight patients, but data on central obesity are scarce. This study was done to assess the relationship between central obesity and the characteristics of migraine attacks in migraine patients. Materials and Methods: This cross-sectional study was conducted on 129 migraine patients (28 men and 101 women), aged 15–67 years, in Isfahan, Iran. Anthropometric measurements such as waist circumference (WC), hip circumference (HC), waist–hip ratio (WHR) and waist–height ratio (WHtR), as well as characteristics of migraine attacks such as severity, frequency, duration, and headache diary result (HDR) was determined for each participant. Linear regression was used to examine the association between anthropometric measurements and characteristics of migraine attacks. P value less than 0.05 was considered significant. Results: WC, WHR, and WHtR were positively associated with the severity (P-value: WC: 0.002, WHR: 0.002, WHtR: 0.001) and frequency (P-value: WC: 0.006, WHR: 0.01, WHtR: 0.002) of migraine attacks. Moreover, we found a significant association between WC (P = 0.001), WHR (P = 0.004), and WHtR (P < 0.001) with HDR. No significant relationship was observed between central obesity indicators and duration of migraine attacks. Conclusions: Central obesity indicators were positively associated with the severity and frequency of migraine attacks as well as HDR, but not with duration of attacks. Based on our findings, it can be concluded that weight loss may decrease the characteristics of migraine attacks