Does consanguinity increase the risk of schizophrenia? Study based on primary health care centre visits

Background Consanguinity has been suggested as a risk factor for the development of schizophrenia in offspring in some Middle Eastern countries.Aim The purpose of this study was to review the frequency, pattern of parental consanguinity, and family history of schizophrenia among schizophrenia patients in Qatar, and to determine their impact on the associated risk factors.Design This is a cross-sectional study which was conducted between January 2009 and December 2010, in the setting of primary health care (PHC) centres of the Supreme Council of Health, State of Qatar.Subjects A total of 1491 patients aged 18–55 years were approached, of whom 1184 individuals agreed to participate in the study, giving a response rate of 79.4%.Methods The study was based on face-to-face interviews using a specially designed questionnaire that covered sociodemographic characteristics and genetic and other biological factors (e.g. obstetric complications), and a diagnostic screening questionnaire which consisted of six questions about the symptoms of schizophrenia. The diagnostic screening questionnaire was reviewed and used to calculate the final score, which determined a provisional diagnosis. The psychiatrists discussed the psychiatric diagnosis and confirmed it using DSM-IV criteria. The degree of consanguinity between the patient''s parents was recorded. Consanguinity was evaluated based on the coefficient of inbreeding (F), which is the probability of homozygosity.Results More than half of the schizophrenia patients were female (57.1%) and over 45 years of age (62.5%). A family history of schizophrenia was significantly more common in parents of schizophrenia patients than in the Arab population without schizophrenia (24.6% vs. 17.1%; P = 0.038). Parental consanguinity was elevated among the patients with schizophrenia (41.3%) with a higher mean coefficient of inbreeding (0.04356 ± 0.028) than in non-schizophrenic subjects (28.7%) with a lower mean coefficient of inbreeding (0.0298 ± 0.035). Schizophrenia diagnoses were more frequent among the offspring of consanguineous parents than among the offspring of non-consanguineous parents.Conclusion The substantial risk observed in the present study reveals that consanguinity is an important risk factor for schizophrenia in Qatar. In addition, the study confirms that the higher familial risks provide strong genetic epidemiological evidence for the overall heritable effects in the aetiology of schizophrenia.     

Liposomal co-delivery-based quantitative evaluation of chemosensitivity enhancement in breast cancer stem cells by knockdown of GRP78/CLU

Resistance to chemotherapy is a key factor in the inefficacy of various forms of treatments for cancer. In the present study, chemo-resistant proteins, including glucose-regulated protein 78 (GRP78)/clusterin (CLU) targeted 1,2-dioleoyloxy-3-trimethylammoniumpropane (DOTAP) liposomes, were developed as a delivery system for co-delivery of camptothecin (CPT) and GRP78 siRNA/CLU siRNA. Their drug/gene co-deliveries were quantitatively assessed in cancer stem cells (CSC) and MCF-7 cells. DOTAP-CPT/siRNA were prepared via electrostatic interaction on GRP78 siRNA or CLU siRNA. The size and ζ-potential of liposomes and lipoplexes were measured by dynamic light scattering techniques and electrophoretic light scattering spectrophotometry. The lipoplexes formation was tested by using gel electrophoresis. Immunofluorescence analysis showed that the expression level of CLU and GRP78 were significantly elevated in CSC compared to MCF-7 cells. Transfection and drug-delivery efficiency of DOTAP-CPT/siRNA were quantitatively compared with Lipofectamine 2000. Compared to free CPT, DOTAP-CPT-siCLU delivery in CSC and MCF-7 cells increased transfection efficiency and chemo-sensitivity by 4.1- and 5.9-fold, respectively. On the other hand, DOTAP-CPT-siGRP78 delivery increased transfection efficiency and chemo sensitivity by 4.4- and 6.2-fold in CSC and MCF-7 cells, respectively, compared to free CPT. It is significant that 3?±?1.2-fold increase in transfection efficiency was achieved by lipofectamine. Consequently, an increase in anti-cancer/gene silencing efficacy was quantitatively observed as an effect of DOTAP-CPT/siRNA treatment, which was relatively higher than lipofectamine treatment. Conclusively, our experimental data quantitatively demonstrate that using DOTAP-CPT-siRNA specifically targeting (CSCs) chemo-resistant protein in vitro offers substantial potential for synergistic anti-cancer therapy.     

Soil core and minirhizotron comparison for the determination of root length density

Detailed knowledge of the distribution of roots in the soil is important in understanding the extraction of water and nutrients from soil. Various techniques have been developed to monitor root-length density under field conditions. Excavation techniques, including soil cores, have long been considered to give reliable estimates of root-length density, but these techniques are laborious in sample collection and tedious in determination of root lengths. An attractive alternative for monitoring root-length density has been the minirhizotron whereby a periscope is inserted into a clear tube permanently installed in the soil for repeated and rapid measures of root development. The objective of this study was to compare the ability of the minirhizotron technique to measure root-length density as compared to the root-core technique.As in previous studies, substantial disagreement existed between the two techniques in the top 30-cm of the soil. The results from the minirhizotron consistently indicated a much lower root population than the root-core technique in the surface layer of soil. This is especially worrisome because more than 45% of the root-length density was found in this layer with the root-core technique. At deeper soil layers, the minirhizotron data proved to be no less variable than the root-core technique making the determination of statistically significant results difficult. Finally, the relationship between the minirhizotron and soil-core results varied with time even when the observations from the soil surface layer were ignored. Attempts to directly translate minirhizotron observations into a root-length density using a correlation approach would be suspect based on the results of this experiment.Mention of company names or commercial products does not imply recommendation or endorsement by the United States Department of Agriculture over others not mentioned.     

Diversity and composition of trees and shrubs in Kasagala forest: a semiarid savannah woodland in central Uganda

The diversity and composition of trees and shrubs of ≥5 cm diameter at breast height (DBH) were investigated in Kasagala woodland in central Uganda using 1 ha permanent sample plots. A total of 2745 trees and shrubs with a mean stem density of 686 ha⁻¹ were recorded. These included 69 tree species belonging to 28 families and 47 genera. There was a larger number of small stems compared with that of larger stems. There was significant variation in stem size class distribution between the plots ( F  =   3.14, P  =   0.027). The variation in stem densities (counts) across different size classes was significant ( F  =   8.31, P  <   0.001). Species diversity was higher in the low lands compared with that in the elevated sites in the woodland. The species encountered were unevenly distributed across the plots. Species abundance was not significantly different across the sample plots ( F  =   2.63, P  =   0.053). We suggest that the structure of the forest is typical of any regenerating forest, but other human influences may have played a part in the dominance of size classes <10 cm DBH. The causes of the present status and composition of the woodland require further investigation.     

Testing of an ammonia ion selective electrode for ammonia nitrogen measurement in the methanogenic sludge

Summary The ammonia ion selective electrode method was the most practical and the most convenient one for measuring the ammonia nitrogen in methanogenic sludge. This is because of its simplicity, rapidity, high precision and accuracy, freedom from interference, small sample size, and possibility for continuous monitoring.