Malaria and ovalocytosis--molecular mimicry?

Two recently published reports have described findings which will have a profound impact on the understanding of molecular mechanisms of human resistance to malaria infection. In Melanesian ovalocytosis, a genetic polymorphism found in Papua New Guinea and parts of South East Asia, the red cells are highly resistant to invasion by various species of malaria parasite. The molecular nature of the defect in ovalocytic erythrocytes was not known. Recent reports by Liu et al. (Liu, S.-C., Zhai, S., Palek, J., Golan, D., Amato, D., Hassan, K., Nurse, G., Babona, D., Coetzer, T., Jarolim, P. Zaik, M. and Borwein, S. (1990) N. Engl. J. Med. 323, 1530-1538.) and Jones et al. (Jones, G.L., Edmundson, H.M., Wesche, D. and Saul, A. (1991) Biochim. Biophys. Acta 1096, 33-40.) have now identified the abnormality in the band 3 protein of ovalocytic red cell membranes. A major discovery in the Jones et al. study is the presence of an extended peptide at the N-terminus of ovalocyte band 3 protein. This novel 13 amino acid extended sequence is not found in the primary structure of normal band 3 protein and was suggested to be the cause of band 3 defect in ovalocytes. We have analyzed this extended sequence through Genbank using SWISS-PROT database and found that an almost identical sequence exists in a malaria parasite protein called RESA.     

Visual persistence and cinema?

In Faraday and Plateau's days, both apparent motion and the fusion of intermittent lights, two phenomena that are hardly connected, were explained by retinal persistence. The works of Exner and of the 'Gestalt' psychologists, as well as the modern works on 'sampled' motion and smooth motion, disregarded retinal persistence. One tried, originally, to measure this persistence using intermittent stimulation, but under the pressure of practical concern, what was established in 1902 was the logarithmic relation between fusion frequency and the intensity of the stimulation. One had to wait until the 1950s for the use of harmonic analysis to finally allow a renewal in which many problems that, for decades, had only given rise to discussions that led nowhere and to groundless assertions, were correctly stated and easily solved.     

Why rods and cones?

In continuation of a previous paper, the auxiliary signal focussing properties of more complicated spinal neuronal networks are considered here. Special emphasis is put on the distributive function of the recurrent feedback system of -motoeurones, but also the inhomogeneous distribution of excitatory and inhibitor input to motoneurones is taken into account as an essential prerequisite for signal focussing. Simple hypothetical calculations for steady-state conditions yield a more vivid insight into the interaction of the two types of neuronal circuitry contributing to signal focussing.     

Why cancer and inflammation?

Central to the development of cancer are genetic changes that endow these “cancer cells” with many of the hallmarks of cancer, such as self-sufficient growth and resistance to anti-growth and pro-death signals. However, while the genetic changes that occur within cancer cells themselves, such as activated oncogenes or dysfunctional tumor suppressors, are responsible for many aspects of cancer development, they are not sufficient. Tumor promotion and progression are dependent on ancillary processes provided by cells of the tumor environment but that are not necessarily cancerous themselves. Inflammation has long been associated with the development of cancer. This review will discuss the reflexive relationship between cancer and inflammation with particular focus on how considering the role of inflammation in physiologic processes such as the maintenance of tissue homeostasis and repair may provide a logical framework for understanding the connection between the inflammatory response and cancer.     

Rise and Demise of Bioinformatics? Promise and Progress

The field of bioinformatics and computational biology has gone through a number of transformations during the past 15 years, establishing itself as a key component of new biology. This spectacular growth has been challenged by a number of disruptive changes in science and technology. Despite the apparent fatigue of the linguistic use of the term itself, bioinformatics has grown perhaps to a point beyond recognition. We explore both historical aspects and future trends and argue that as the field expands, key questions remain unanswered and acquire new meaning while at the same time the range of applications is widening to cover an ever increasing number of biological disciplines. These trends appear to be pointing to a redefinition of certain objectives, milestones, and possibly the field itself.     

Serological and genetic analysis of ABO ambiguous blood group samples

The accuracy of regular serum methods to detect ABO blood groups can be negatively affected by some factors, such as irregular antibodies, autoantibodies or effects of diseases leading to false or weak agglutination. This study aimed to accurately identify ambiguous ABO blood groups by serological and gene detection methods. The samples were collected in the First Affiliated Hospital of Nanjing Medical University from December 2018 to December 2019. ABO genotyping was performed by polymerase chain reaction-sequence specific primer (PCR-SSP) method in 20 samples, and ABO exons 6 and 7 or FUT1 and FUT2 genes were sequenced in 5 samples. The genes detected in the 21 specimens included 4 cases of A/B, 2 cases of A205/O01, 3 cases of A/O01, 3 cases of A/O02, 1 case of O01/O01, 1 case of O01/O02, 1 case of B/O01, 1 case of B/O02, 1 case of Bel/O01, 1 case of Cisab01/O01, 1 case of rare B/O04, 1 case of Bombay-like Bmh, 1 case of new gene showing c.261del G of exon 6, c.579 T>C of exon 7 and B new/O01. This study suggests that ABO blood group genotyping technology combined with serological typing can be used for accurately typing ambiguous blood groups.     

ABO blood group system

The accuracy of regular serum methods to detect ABO blood groups can be negatively affected by some factors, such as irregular antibodies, autoantibodies or effects of diseases leading to false or weak agglutination. This study aimed to accurately identify ambiguous ABO blood groups by serological and gene detection methods. The samples were collected in the First Affiliated Hospital of Nanjing Medical University from December 2018 to December 2019. ABO genotyping was performed by polymerase chain reaction-sequence specific primer (PCR-SSP) method in 20 samples, and ABO exons 6 and 7 or FUT1 and FUT2 genes were sequenced in 5 samples. The genes detected in the 21 specimens included 4 cases of A/B, 2 cases of A205/O01, 3 cases of A/O01, 3 cases of A/O02, 1 case of O01/O01, 1 case of O01/O02, 1 case of B/O01, 1 case of B/O02, 1 case of Bel/O01, 1 case of Cisab01/O01, 1 case of rare B/O04, 1 case of Bombay-like Bmh, 1 case of new gene showing c.261del G of exon 6, c.579 T > C of exon 7 and B new/O01. This study suggests that ABO blood group genotyping technology combined with serological typing can be used for accurately typing ambiguous blood groups.     

B para-Bombay phenotype in China caused by homozygous mutation for site 328 G>A of FUT1 gene: a case report

The aim of this paper is to accurately identify a case of B para-Bombay and to analyze the genetic mutation. ABO and Lewis blood groups were identified by standard serological methods, and trace antigens on RBCs were detected by adsorption-elution test, while blood group substances in the saliva were detected by agglutination inhibition test. The ABO gene exons 6-7, FUT1 gene exon 4 and FUT2 gene exon 2 were directly sequenced. Serological results showed that there were B antigens on RBCs without H antigens, anti-A and anti-HI antibodies in serum, and B and H blood group substances in the saliva. The Lewis phenotype was Le (a-b+). According to gene sequencing analysis, ABO, FUT1 and FUT2 genotypes were B101/O02, h^328G/Ah^328G/A and Se^357C/TSe^357C/T, respectively. This rare phenotype can be mislabeled as "O" if any of the detailed investigations are not performed. Therefore, in order to ensure the safety of blood transfusion, genetic and serological tests are necessary for the correct identification of difficult blood groups.     

B para-Bombay phenotype in China caused by homozygous mutation for site 328 G > A of FUT1 gene: a case report

The aim of this paper is to accurately identify a case of B para-Bombay and to analyze the genetic mutation. ABO and Lewis blood groups were identified by standard serological methods, and trace antigens on RBCs were detected by adsorption-elution test, while blood group substances in the saliva were detected by agglutination inhibition test. The ABO gene exons 6-7, FUT1 gene exon 4 and FUT2 gene exon 2 were directly sequenced. Serological results showed that there were B antigens on RBCs without H antigens, anti-A and anti-HI antibodies in serum, and B and H blood group substances in the saliva. The Lewis phenotype was Le (a-b+). According to gene sequencing analysis, ABO, FUT1 and FUT2 genotypes were B101/O02, h^328G/Ah3^28G/A and Se^357C/TSe^357C/T, respectively. This rare phenotype can be mislabeled as "O" if any of the detailed investigations are not performed. Therefore, in order to ensure the safety of blood transfusion, genetic and serological tests are necessary for the correct identification of difficult blood groups.     

The incidence and features of serological ABO subgroups among one million blood donors in Beijing

This study aims to determine the incidence of serological ABO subgroups from a large-scale database, along with the features of blood samples with serological ABO discrepancies. The serological ABO results of one million individuals were randomly sampled from a blood donor database in Beijing between 2009 and 2010. All samples were diagnosed by serological reverse and forward ABO typing using an automatic analyzer. The proportions of the normal ABO types were 27.28%, 31.57%, 30.56%, and 10.16% for blood types A, B, O, and AB, respectively. In samples in which ABO discrepancies or obvious weak agglutinin were identified in the forward or reverse typing, further tests to analyze the ABO subgroup were conducted. The overall incidence of ABO subgroups was 0.047%, with 14 ABO subgroups observed: A2, A3, Ax, Am, Aint, Aend, B2, B3, Bx, Bm, Bel, B(A), cisAB, and AB^h. In conclusion, this study revealed the exact normal ABO and subgroup distributions in the general, healthy population of Beijing using samples from a blood donor database.     

Molecular genetic analysis of the ABO blood group system: 3. A(X) and B(A) alleles

B(A) is a rare ABO blood subgroup. Here we reported a B(A)02/O01 case. One 25-year-old female patient showed inconsistent forward and reverse blood grouping results based on micro-column gel agglutination assay. PCR-SSP and PCR-SBT based genotyping indicated that the patient was B(A)02/O01 heterozygous.     

Rare B(A)02/O01 was found in Sichuan again: a case report

B(A) is a rare ABO blood subgroup. Here we reported a B(A)02/O01 case. One 25-year-old female patient showed inconsistent forward and reverse blood grouping results based on micro-column gel agglutination assay. PCR-SSP and PCR-SBT based genotyping indicated that the patient was B(A)02/O01 heterozygous.     

Consistency of ABO blood group phenotypes and genotypes in renal transplant patients

The aim of this study was to confirm the concordance between the ABO phenotype and genotype in 34 patients undergoing renal transplant before 2010 in Sir Run Run Shaw Hospital. The ABO genotyping kit and column agglutination test (CAT) were used to examine the ABO type, and ABO subgroup was checked by sequence analysis of ABO exons 6 and 7. We found that the genotypes of serological A, AB, O, and B patients were A1A1 in 3 patients and A1O1 in 5 patients, A1B, O1O2 in 1 patient and O1O1 in 11 patients, and BB in 6 patients and BO1 in 6 patients, respectively. However, one patient, who was originally reported as serological B in the 2010 medical record and CAT showed Asub B in 2016 and sequence analysis of ABO exons 6 and 7 demonstrated B(A)04/O1.[not clear] The ABO column agglutination testing combined with genotyping may provide additional value in pre-renal transplantation laboratory examinations, and it may be safe to transplant a B/O1 kidney to a B(A)04/O1 recipient since the transplantation has been success for 6 years.     

Serological and molecular analysis of ABO and Rh blood group chimeras

The serological examination, blood transfusion strategies and the molecular analysis to blood group chimera were conducted to demonstrate existent of chimera in blood group. The blood grouping of ABO or/and RhD, newborn red blood cells separated by capillary centrifugation. Aabsorption tests and DTT treated agglutination erythrocyte tests were implemented in four patients. Further molecular biological research was conducted on one patient''s sample. The results showed that for patient 1: ABO blood group was AB/B chimera, Rh blood cells contained the RhCE chimera gene; Patient 2: Rh blood cells contained the RhD chimera gene; Patient 3: ABO blood group was AB/B chimera, Rh blood cells contained the RhD chimera gene; Patient 4: ABO blood group was O/B chimera, Rh blood cells contained the RhCE chimera gene. The study suggests that the individuals categorized as chimeras are likely to be more common than existing literature reports. According to the serological tests, in the absence of a history of recent blood transfusion or disease to cause reduced antigen, the phenomena of hybrid aggregation of the ABO and Rh blood system were the main feature. In terms of transfusion strategy, the selection of ABO and Rh blood groups should be depended on the group of cells with more antigens.     

Serology and gene sequence analysis of rare subgroup A3 blood group

To investigate the serological phenotypic characteristics and possible mechanism of subgroup A₃, a blood donor's ABO phenotypes were detected by the conventional microcolumn gel method and classic tube method. N-acetylgalactosaminyl transferase activity was detected by the non-radioactive phosphate coupling method. ABO subtype genotyping was determined by PCR-SSP and exons 1-7 of ABO gene were analyzed by Sanger sequencing. The donor's blood type was subgroup A₃ as evaluated by serological test. There was no N-acetylgalactosaminyl transferase activity in the red blood cells and weak N-acetylgalactosaminyl transferase activity in the plasma. The ABO blood group genotyping result was ABO*AO1, and the gene sequencing result was confirmed as A221/O01. Sequencing results showed two mutations, 467C>T and 607G>A in exon 7 in ABO*A allele. In conclusion, it is suggested that the ABO blood group of the donor be subgroup A₃, which may be induced by mutations 467C>T and 607G>A, and led to a decrease in N-acetylgalactosaminyl transferase activity and resulted in weakened A antigen.