bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three novel CYP21A2 mutations and their protein modelling in patients with classical 21‐hydroxylase deficiency from northeastern Iran
Authors: Baradaran‐Heravi Alireza , Vakili Rahim , Robins Tiina , Carlsson Jonas , Ghaemi Nosrat , A’rabi Azadeh , Abbaszadegan Mohammad Reza 
Published: June 2007

SummaryObjective  Congenital adrenal hyperplasia (CAH) refers to a group of autosomal recessive disorders frequently caused by mutations in the steroid 21‐hydroxylase gene (CYP21A2). We describe three novel CYP21A2 mutations in CAH patients.Design and methods  Sequence analysis of the entire CYP21A2 gene followed by molecular modelling was performed in three unrelated classical CAH patients of northeastern Iranian origin. The active (CYP21A2) and pseudogene (CYP21A1P) alleles were screened for the presence of the new variations in controls.Results  Two novel missense mutations, F404S in exon 9 and T450P in exon 10, were found in homozygous forms in two female patients with a salt‐wasting (SW) phenotype. These novel variants were screened by allele‐specific polymerase chain reaction (PCR) and excluded in 100 unrelated normal alleles. Prediction of clinical severity, based on molecular modelling and sequence conservation, correlates well with the clinical diagnosis of the patients carrying these mutations. The third novel mutation, a small 10‐bp deletion in exon 1, g.19_28del, was found in a female patient with a simple virilizing phenotype in a compound heterozygous form with the common intron 2 splice mutation (IVS2–13A/C>G). This frameshift mutation causes a premature stop codon at amino acid position 48, L48X, resulting in a nonfunctional protein. The CYP21A1P pseudogene alleles were also screened and none of these novel mutations could be detected.Conclusions  Three novel mutations were found in the CYP21A2 gene and predicted to drastically impair enzyme activity resulting in severe classic CAH. None of these mutations occurs in the CYP21A1P pseudogene.
Diagnosis and treatment of low‐renin hypertension
Authors: Mulatero Paolo , Verhovez Andrea , Morello Fulvio , Veglio Franco 
Published: June 2007

SummaryPlasma renin levels can be used to classify hypertension. A significant proportion of hypertensive individuals display a low‐renin profile and thus low‐renin hypertension (LRH) requires appropriate diagnosis and treatment. LRH includes essential, secondary and genetic forms, the most common of which are low‐renin essential hypertension and primary aldosteronism. Several studies have investigated the relationship between PRA status and clinical response to different antihypertensive therapies. The present review will discuss the differential diagnosis of LRH subtypes and the most appropriate treatment options based on the pathophysiological background of this condition.
RET proto‐oncogene mutations are restricted to codons 634 and 918 in mainland Chinese families with MEN2A and MEN2B
Authors: Zhou Yulin , Zhao Yongju , Cui Bin , Gu Liqun , Zhu Shaoxin , Li Jianjun , Liu Jinbo , Yin Ming , Zhao Tieyun , Yin Zhiqiang , Yu Chaoli , Chen Changyou , Wang Liming , Xiao Buyun , Hong Jie , Zhang Yifei , Tang Zhengyi , Wang Shu , Li Xiaoying , Ning Guang 
Published: June 2007

SummaryObjective  Multiple endocrine neoplasia type 2 is caused by autosomal dominant gain‐of‐function mutations in the RET proto‐oncogene, which includes multiple endocrine neoplasia type 2A (MEN2A), type 2B (MEN 2B), and familial medullary thyroid carcinoma (FMTC). In this paper we present the phenotype–genotype correlation of 20 unrelated Chinese families with 15 cases of MEN2A and five cases of MEN2B.Design  Cross‐sectional study.Patients  A total of 147 members from the 20 families were included. Among them, 119 family members were from MEN2A pedigrees (including 15 MEN2A probands) and 28 members from MEN2B pedigrees (including five MEN2B probands).Measurements  Genomic DNA was isolated from peripheral blood leucocytes and was amplified using polymerase chain reaction (PCR). DNA analysis for RET mutations in exons 8, 10, 11, 13, 14, 15 and 16 was performed with specific primers.Results  Thirty‐seven MEN2A and five MEN2B patients were identified as having RET mutations. The incidence of medullary thyroid carcinoma (MTC), pheochromocytoma (PCC) and hyperparathyroidism (HPT) in the 37 MEN2A patients was 91·9, 56·8 and 10·8%, respectively; the onset of MTC in MEN2A patients was earlier than that of PCC and HPT. Five germline mutations, all located at codon 634 of exon11 in the RET proto‐oncogene, were detected in all of the 37 MEN2A patients. The highest frequency of the five germline mutations was C634Y (46·7%), followed by C634R (26·7%), C634W (13·3%), C634F (6·7%) and C634S (6·7%). No statistical significance was found between the incidence of PCC and different genotypes of codon 634 in MEN2A patients, whereas the incidence of HPT was closely associated with C634R and C634Y. The gene mutation (M918T) at exon16 of the RET proto‐oncogene was present in five MEN2B probands.Conclusions  RET proto‐oncogene mutations were restricted to codon 634 and 918 in Chinese families with MEN2A and MEN2B. In general the genetic characteristics of these patients with MEN2A and MEN2B reflect the general pattern around the world and it remains to be determined with larger studies in China whether Chinese patients have a different genetic pattern of mutations.
Altered expression of adhesion molecules in inflammatory cervical smears
Authors: Politi E. N. , Lazaris A. C. , Kehriotis M. , Papathomas T. G. , Nikolakopoulou E. , Koutselini H. 
Published: June 2007

Objective:  The aim of the present study was to evaluate the expression of pan‐cadherin and β‐catenin in cervical smears with various types of infectious agents.Patients and Methods:  Cervical smears obtained from 53 women, aged 21–65 years, with a diagnosis of specific inflammation were examined in our study. Eighteen subjects were infected by Candida albicans, 18 by Gardnerella vaginalis, nine by Bacteroides spp. and eight by Chlamydia trachomatis. All infectious agents found in the smears were at the same time confirmed by the microbiological laboratory methods. We performed a biotin–streptavidin‐peroxidase immunocytochemical method using anti‐β‐catenin (Clone 12F7) and anti‐pan‐cadherin (pan, polyclonal) antibodies.Results:  Aberrant expression of pan‐cadherin was found in the cytoplasmic membrane of glandular, metaplastic, superficial and intermediate squamous cells in all types of infections. With regard to β‐catenin, this was expressed in majority (90%) of glandular and metaplastic cells in all types of infections and in a small proportion (15%) of superficial and intermediate squamous cells in infections caused by C. albicans and G. vaginalis.Conclusion:  Our data show that infectious agents may cause alterations in the expression and distribution of these adhesive molecules, which can be recognized in cervical smears. Additional studies in larger sets of patients should help clarify this issue further.
Altered endothelial gene expression associated with hereditary haemorrhagic telangiectasia
Authors: Thomas B. , Eyries M. , Montagne K. , Martin S. , Agrapart M. , Simerman‐François R. , Letarte M. , Soubrier F. 
Published: June 2007

AbstractBackground  Mutations in endoglin (ENG) and activin receptor‐like kinase 1 (ALK‐1 or ACVRL1) genes are the underlying basis of hereditary haemorrhagic telangiectasia (HHT) types 1 and 2, respectively. Both genes belong to the transforming growth factor‐β (TGF‐β) receptors superfamily and are expressed in endothelial cells. The current model for HHT is that ENG or ALK‐1 haplo‐insufficiency affects angiogenesis and predisposes to vascular dysplasia and arteriovenous malformations.Materials and methods  Using microarray technology, we compared human umbilical vein endothelial cells (HUVEC) from newborns with ENG or ALK‐1 mutations to control cells to search for gene profiles associated with early stages of the disease. Real‐time polymerase chain reaction and Western blot analysis were used to validate a subset of the modulated genes and functionally related genes.Results  Our results indicate that HHT endothelial cells in vitro display several gene expression disturbances, including genes associated with the activation phase of angiogenesis, with cell guidance and intercellular connections, and also with the TGF‐β pathway. Hierarchical clustering using modulated genes enables discrimination between affected and non‐affected samples.Conclusion  HHT HUVECs display gene modulations which can suggest that ENG and ALK‐1 haplo‐insufficiency induces compensatory regulatory mechanisms at the expression levels.
Effects of infectious disease on plasma lipids and their diagnostic significance in critical illness
Authors: Lüthold S. , Berneis K. , Bady P. , Müller B. 
Published: June 2007

AbstractBackground  Plasma lipids can be affected by acute illnesses. The present study attempts to characterize the impact of infectious disease on plasma lipids in critical illness. It also aims to determine the value of plasma lipid routine measurements in the diagnosis of infection in critical illness in comparison to markers of infection and acute phase reactants.Materials and methods  An observational study was carried out in 101 critically ill patients admitted consecutively to a medical intensive care unit in a university medical centre. Levels of total cholesterol (TC), high‐density lipoprotein cholesterol (HDL‐C), triglycerides (TG), and additional variables were measured in blood samples taken on the day of admission.Results  In critically ill patients significantly lower levels of HDL‐C and TC were found in infectious disease patients compared to non‐infectious disease patients (P < 0·001). No significant differences in levels of TG were found between infectious and non‐infectious disease patients. Using receiver operating characteristic (ROC) curve analysis, the area under the curve (AUC) value for HDL‐C and TC in the diagnosis of infection was 0·791 (P < 0·001) and 0·730 (P < 0·001), respectively. At a cutoff value for HDL‐C of ≤ 0·78 mmol L−1, a sensitivity of 71·7% and a specificity of 86·0% were recorded. The AUC value of HDL‐C was significantly (P < 0·001) inferior to procalcitonin (AUC: 0·967, P < 0·001) and non‐significantly inferior to C‐reactive protein (CRP) (AUC: 0·874, P < 0·001). HDL‐C correlated with albumin (r = 0·7, P < 0·001) and CRP (r = –0·54, P < 0·001), but not with the Acute Physiology and Chronic Health Evaluation II score. There was no significant difference between the plasma lipid concentrations in survivors and non‐survivors.Conclusion  In critically ill infected patients, HDL‐C and TC levels are lower than in non‐infected critically ill patients. In this study the diagnostic accuracy of CRP is not better than the one of HDL‐C. The diagnostic accuracy of procalcitonin is superior to HDL‐C.
Mutations of chronic granulomatous disease in Turkish families
Authors: Köker M. Y. , Sanal Ö. , De Boer M. , Tezcan İ. , Metin A. , Ersoy F. , Roos D. 
Published: June 2007

AbstractBackground  Chronic granulomatous disease (CGD) is an inherited disorder of the innate immune system characterized by impairment of intracellular microbicidal activity of phagocytes. Mutations in one of four known NADPH‐oxidase components preclude generation of superoxide and related antimicrobial oxidants, leading to the phenotype of CGD. Defects in gp91‐phox, encoded by CYBB, lead to X‐linked CGD and have been reported to be responsible for approximately 70% of all CGD cases. The aim of this study was to identify the CGD mutations in a group of Turkish CGD patients and to evaluate the predominance of CGD mutations as X‐linked or autosomal recessive (AR) within the Turkish CGD families with known mutations.Materials and methods  Two Turkish CGD families were included in the study, and mutations were identified by sequence analysis of DNA and RNA from peripheral blood in the patients. Before mutation analysis, subgroup analysis of patients was made by flow cytometry with antibodies against NADPH oxidase components and with DHR‐123 oxidase activity assay. For comparison, we included previously reported results from four other Turkish CGD families.Results  Two different mutations were identified, one of them a novel mutation g.700G>T located in exon 7 of CYBB, and the other a hot‐spot mutation located in exon 2 of the NCF1 gene. These mutations were detected in three patients from two Turkish families.Conclusions  Until now, we have altogether identified mutations in six Turkish CGD families. In this limited number of families our results show AR‐CGD in two‐thirds of the Turkish families investigated, in contrast to previous reports in the literature. This is probably due to the high rate of consanguineous marriages in Turkey. Consanguineous parents were found in 75% of the families with AR‐CGD patients, which favours homozygous deficiencies.
Denitrification characteristics of subtropical soils in China affected by soil parent material and land use
Authors: Xu Y. B. , Cai Z. C. 
Published: June 2007

SummaryForty‐five soil samples were collected from rice paddy land (R), tea garden land (T), forestland (F), brush land (B), and upland (U) in Jiangxi province, a subtropical region of China. These soils were derived from Quaternary red earth (Q), Tertiary red sandstone (S), and granite (G). Their denitrification capacities were determined after treatment with 200 mg NO3−‐N kg−1 soil by measuring changes in NO3−‐N content during a 28‐day anaerobic incubation under N2 gas in the headspace, at 30°C. The subtropical soils studied here were characterized by generally small denitrification capacities, ranging from no denitrification capacity to complete disappearance of added NO3−‐N within 11 days of incubation. With few exceptions, NO3−‐N reduction with incubation time followed a first‐order relationship with reaction constants of 0 – 0.271 day−1, but the data could be simulated better by a logarithmic relationship. Thus, denitrification capacity was determined by the reaction constant of the first‐order reaction, the slope of the logarithmic relationship, and the averaged NO3−‐N reduction rate in the first 7 days of anaerobic incubation (ranging from 0 to 28.5 mg kg−1day−1), and was significantly larger in the soils derived from G than from Q and S for all land uses except for rice paddy land. Soil organic carbon and nitrogen availability are the key factors that determine differences in denitrification capacity among the three soil parent materials. Rice cultivation significantly promoted denitrification capacity compared with the other four land uses and masked the effect of soil parent materials on denitrification capacity. This is most likely due to increases in organic carbon and total N content in the soil, which promoted the population and biological activities of microorganisms which are able to respire anaerobically when the rice soil is flooded. Neither the increased pH of upland soil caused by the addition of lime for upland crop production, nor the decreased pH of the tea garden soil by the acidification effect of tea plants altered soil denitrification capacity. Our results suggest that land use and management practices favour soil carbon and/or nitrogen accumulation and anaerobic microorganism activities enhance soil denitrification capacity.
Comparison of chemical fractionation methods for isolating stable soil organic carbon pools
Authors: Helfrich M. , Flessa H. , Mikutta R. , Dreves A. , Ludwig B. 
Published: June 2007

SummaryStable soil organic matter (SOM) is important for long‐term sequestration of soil organic carbon (SOC), but the usefulness of different fractionation methods to isolate stable SOM is open to question. We assessed the suitability of five chemical fractionation methods (stepwise hydrolysis, treatment with H2O2, Na2S2O8, NaOCl, and demineralization of the NaOCl‐resistant fraction (NaOCl + HF)) to isolate stable SOM from soil samples of a loamy sand and a silty loam under different land use regimes (grassland, forest and arable crops). The apparent C turnover time and mean age of SOC before and after fractionation was determined by 13C and 14C analysis. Particulate organic matter was removed by density fractionation before soils were exposed to chemical fractionation. All chemical treatments induced large SOC losses of 62–95% of the mineral‐associated SOC fraction. The amounts of H2O2‐ and Na2S2O8‐resistant SOC were independent from land use, while those of NaOCl‐ (NaOCl + HF)‐ and hydrolysis‐resistant SOC were not. All chemical treatments caused a preferential removal of young, maize‐derived SOC, with Na2S2O8 and H2O2 being most efficient. The mean 14C age of SOC was 1000–10000 years greater after chemical fractionation than that of the initial, mineral‐associated SOC and mean 14C ages increased in the order: NaOCl < NaOCl + HF ≤ stepwise hydrolysis ≪ H2O2≈ Na2S2O8. None of the methods appeared generally suitable for the determination of the inert organic matter pool of the Rothamsted Carbon Model. Nonetheless, our results indicate that all methods are able to isolate an older, more stable SOC fraction, but treatments with H2O2 and Na2S2O8 were the most efficient ones in isolating stable SOM.
Multidecadal to millennial‐scale shifts in drought conditions on the Canadian prairies over the past six millennia: implications for future drought assessment
Authors: MICHELS ASTRID , LAIRD KATHLEEN R. , WILSON SUSAN E. , THOMSON DAVID , LEAVITT PETER R. , OGLESBY ROBERT J. , CUMMING BRIAN F. 
Published: June 2007

AbstractThree high‐resolution climatic reconstructions, based on diatom analyses from lake sediment cores from the Canadian prairies, show that shifts in drought conditions have prevailed on centennial to millennial time scales for at least the past six millennia. These shifts in mean aridity exhibit broad regional synchrony, with particularly pronounced shifts at all sites between ∼1700–2000 cal. yr bp and ∼3600–3900 cal. yr bp, as well as at ∼5400–5500 cal. yr bp for the two sites which extend back to at least 6000 cal. yr bp. The two Saskatchewan lakes exhibited significant coherence in both the timing and direction of these shifts, whereas inferred changes at the westernmost site in Alberta were significantly correlated to the Saskatchewan sites, but opposite in sign, and exhibited more high‐frequency variation on the scale of centuries. The mechanisms behind these abrupt shifts in aridity are poorly understood, but may be linked to changes in oceanic–atmospheric interactions that influence the mean position of the jetstream and the associated storm tracks. Natural shifts in mean climatic conditions may accelerate with increasing carbon dioxide levels intensifying the likelihood of extreme droughts in North American prairies.
Development of a stable isotope index to assess decadal‐scale vegetation change and application to woodlands of the Burdekin catchment, Australia
Authors: KRULL EVELYN , BRAY STEVEN , HARMS BEN , BAXTER NATHALIE , BOL ROLAND , FARQUHAR GRAHAM 
Published: June 2007

AbstractForty‐four study sites were established in remnant woodland in the Burdekin River catchment in tropical north‐east Queensland, Australia, to assess recent (decadal) vegetation change. The aim of this study was further to evaluate whether wide‐scale vegetation ‘thickening’ (proliferation of woody plants in formerly more open woodlands) had occurred during the last century, coinciding with significant changes in land management. Soil samples from several depth intervals were size separated into different soil organic carbon (SOC) fractions, which differed from one another by chemical composition and turnover times. Tropical (C4) grasses dominate in the Burdekin catchment, and thus δ13C analyses of SOC fractions with different turnover times can be used to assess whether the relative proportion of trees (C3) and grasses (C4) had changed over time. However, a method was required to permit standardized assessment of the δ13C data for the individual sites within the 13 Mha catchment, which varied in soil and vegetation characteristics. Thus, an index was developed using data from three detailed study sites and global literature to standardize individual isotopic data from different soil depths and SOC fractions to reflect only the changed proportion of trees (C3) to grasses (C4) over decadal timescales. When applied to the 44 individual sites distributed throughout the Burdekin catchment, 64% of the sites were shown to have experienced decadal vegetation thickening, while 29% had remained stable and the remaining 7% had thinned. Thus, the development of this index enabled regional scale assessment and comparison of decadal vegetation patterns without having to rely on prior knowledge of vegetation changes or aerial photography.
Oxidative stress biomarkers and hormonal profile in human patients undergoing varicocelectomy
Authors: Hurtado de Catalfo Graciela E. , Ranieri‐Casilla Adalberto , Marra Fernando A. , De Alaniz María J. T. , Marra Carlos A. 
Published: June 2007

SummaryThe aetiology of varicocele is multifactorial although hormonal imbalance and oxidative stress play a key role in the progression of illness. No conclusive evidence has been presented previously, describing the changes in these two factors and the evolution of patients after varicocelectomy. Semen characteristics and hormonal profile were analysed in 36 infertile men with unilateral left varicocele and 33 age‐paired controls (proved to be fertile men), after careful inclusion/exclusion selection criteria. Liposoluble and hydrosoluble antioxidants, oligoelements and enzyme activities of the antioxidant defence system were also determined in plasma and erythrocyte from antecubital and spermatic veins, and in spermatozoa. Data were compared between groups at different times before and after varicocelectomy. Decreased levels of liposoluble and hydrosoluble antioxidants and increased activities of the antioxidant defence system enzymes were observed in patients compared with controls. Varicocelectomy normalized this condition at different post‐surgical times. Levels of Zn and Se in seminal plasma, protein carbonyls and fragmented DNA remained elevated up to 1 month after surgery. Luteinizing and follicle stimulating hormone concentrations exhibited a biphasic behaviour while testosterone was diminished in patients but normalized soon after varicocelectomy. The results clearly demonstrate the link between the antioxidant defence system, hormonal status and semen characteristics along the post‐varicocelectomy period. We suggest that oxidative biomarkers may be appropriate in controlling the evolution of post‐varicocelectomy patients, and antioxidant supplementation may improve the clinical condition of infertile men with varicocele.
Fertility treatment in male cancer survivors
Authors: Schmidt Kirsten Louise Tryde , Carlsen Elisabeth , Andersen Anders Nyboe 
Published: June 2007

SummaryThe present study reviews the use of assisted reproductive technology in male cancer survivors and their partners. As antineoplastic treatment with chemotherapy or radiation therapy, has the potential of inducing impairment of spermatogenesis through damage of the germinal epithelium, many male cancer survivors experience difficulties in impregnating their partners after treatment. The impairment can be temporary or permanent. While many cancer survivors regain spermatogenesis months to years after treatment, some become infertile with a‐, oligo‐ or azoospermia. An option to secure the fertility potential of young cancer patients is to cryopreserve semen before cancer treatment for later use. A desired pregnancy may be obtained in couples where the husband has a history of cancer, using assisted reproductive technology with either fresh or cryopreserved/thawed semen. Successful outcomes have been obtained with intrauterine insemination (IUI) as well as in vitro fertilization (IVF) with or without the use of intracytoplasmic sperm injection (ICSI). In conclusion, male cancer survivors and their partners who have failed to obtain a pregnancy naturally within a reasonable time frame after end of treatment should be referred to a fertility clinic.