Treatment of thalassaemia: a review of the new approaches on transfusion safety and the novel therapeutics

Lifetime red cell concentrate (RCC) transfusions still account for significant iron overload‐related morbidity and mortality despite chelation therapy in thalassaemia. The cumulative risk of transfusion‐transmitted infections is substantial for thalassaemia patients. Pathogen reduction technologies for RCC may imply a proactive approach against new/re‐emerging pathogens and may be an ultimate safeguard for transfusion safety in the developing countries. Red cell alloimmunization may become a significant clinical challenge in thalassaemia. The availability of high‐throughput molecular blood group antigen typing in the donors may allow perfect match transfusion, beyond ABO‐D and CEK antigen‐matched transfusions. Allogeneic stem cell transplantation (A‐SCT) is the only available curative therapy in thalassaemia, but carries a substantial risk of serious adverse events and mortality. Gene addition therapy for correction of the α‐globin chain imbalance overcomes the problems of donor availability and immunological complications of A‐SCT. Gene editing by either gene disruption or correction emerged as a potential alternative to gene addition therapy in beta‐thalassaemia. A new era of novel therapeutics targeting α/β imbalance, ineffective erythropoiesis or iron dysregulation is unfolding in thalassaemia management, and a number of those now have agents in preclinical and clinical development. Hydroxyurea (HU) may improve globin chain imbalance and be beneficial for reducing or omitting transfusion requirement. Ruxolitinib has allowed steady decrease in spleen volume that may serve for avoiding splenectomy in beta‐thalassaemia. Luspatercept may restore normal erythroid differentiation and improve anaemia. Hepcidin mimetics or TMPRSS6 inhibitors may modulate ineffective erythropoiesis by iron restriction and improve anaemia and organ iron loading.     

Evaluation of leukocyte arylsulphatase a, serum interleukin-6 and urinary heparan sulphate following tamoxifen therapy in breast cancer.

Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p=0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (p=0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity.     

Season of birth and fluctuating asymmetry.

Fluctuating asymmetry (FA) refers to random, small deviations from perfect bilateral symmetry in morphological traits. These minor deviations from the ideal phenotype reflect environmental and genetic perturbations experienced during ontogeny. FA has been associated with negative health outcomes and many developmental disorders in humans. The prevalence of developmental disorders and adult health vary according to the month of birth, suggesting that seasonal stressors may leave enduring signs in the adult body, marked by high FA. The current study examined the relationship between FA and birth season. Data were collected for 205 males and females (average age = 20.39 years) on FA of 10 bilateral traits (second, third, fourth, and fifth digit length, palm height, wrist diameter, elbow width, ear height, foot breadth, and ankle circumference). Additional relationships were also investigated among FA, testosterone (T), and birth order. Results indicate that ear FA was lower for fall births compared to winter births in males. In females, palm FA was lower for fall births compared to those of the spring. FA of the digits was positively associated with T in males. Average FA, excluding the digits, decreased as the number of maternal siblings increased for both sexes. T concentrations in males were positively associated with the number of younger brothers. Our results generally confirm previous research on seasonal variation in adult longevity and neurological and psychiatric disorders, suggesting that winter and spring births are at risk for asymmetric developmental trajectory.     

Sequence analysis of rpoB mutations in rifampin-resistant clinical Mycobacterium tuberculosis isolates from Turkey

Drug-resistant tuberculosis is a serious problem throughout the world. Resistance to Rifampicin (RIF) is mainly caused by the mutations in the rpoB gene coding the beta-subunit of RNA polymerase. In this study, we aimed to detect the distribution of rpoB gene mutations in 80 RIF-resistant clinical Mycobacterium tuberculosis (MTB) isolates from Turkey. The rpoB gene was amplified by PCR and mutations leading to RIF resistance were determined by automated sequence analysis. A total of 72 of the 80 isolates (90%) were found to carry mutations in the amplified region, whereas eight isolates (10%) carried no mutations. Overall, 24 different missense mutations affecting 14 codons, and two deletion mutants were identified. Nine new mutations, six in the hot-spot region and three outside this region, were found. The codon numbers of the most frequently encountered mutations were 531 (51.4%), 526 (18.1%), 516 (13.9%), and 513 (12.5%). As a result, 90% of the RIF-resistant MTB isolates from the Turkish patients were found to carry a mutation in the rpoB gene, Ser531Leu being the most frequent one. Although molecular methods identify mutations leading to RIF resistance very quickly, results of the antimycobacterial susceptibility tests must be taken into consideration for the patients carrying no mutations in this region.     

The role of cartilage canals in endochondral and perichondral bone formation: are there similarities between these two processes?

We investigated the development of cartilage canals to clarify their function in the process of bone formation. Cartilage canals are tubes containing vessels that are found in the hyaline cartilage prior to the formation of a secondary ossification centre (SOC). Their exact role is still controversial and it is unclear whether they contribute to endochondral bone formation when an SOC appears. We examined the cartilage canals of the chicken femur in different developmental stages (E20, D2, 5, 7, 8, 10 and 13). To obtain a detailed picture of the cellular and molecular events within and around the canals the femur was investigated by means of three-dimensional reconstruction, light microscopy, electron microscopy, histochemistry and immunohistochemistry [vascular endothelial growth factor (VEGF), type I and II collagen]. An SOC was visible for the first time on the last embryonic day (E20). Cartilage canals were an extension of the vascularized perichondrium and its mesenchymal stem cell layers into the hyaline cartilage. The canals formed a complex network within the epiphysis and some of them penetrated into the SOC were they ended blind. The growth of the canals into the SOC was promoted by VEGF. As the development progressed the SOC increased in size and adjacent canals were incorporated into it. The canals contained chondroclasts, which opened the lacunae of hypertrophic chondrocytes, and this was followed by invasion of mesenchymal cells into the empty lacunae and formation of an osteoid layer. In older stages this layer mineralized and increased in thickness by addition of further cells. Outside the SOC cartilage canals are surrounded by osteoid, which is formed by the process of perichondral bone formation. We conclude that cartilage canals contribute to both perichondral and endochondral bone formation and that osteoblasts have the same origin in both processes.     

Long-term use and tolerability of cyclooxygenase-2 inhibitors in patients with analgesic intolerance.

BACKGROUND: Cyclooxygenase-2 (COX-2) inhibitors are reported to be well tolerated in patients with analgesic intolerance (AI). However, limited data are available about the long-term tolerability of these drugs. OBJECTIVE: To determine the long-term tolerability of COX-2 inhibitors in patients with Al. METHODS: Patients with AI who previously underwent single-masked, placebo-controlled oral provocation tests and were found to tolerate nimesulide, meloxicam, rofecoxib, or celecoxib were interviewed regarding the long-term use and tolerability of these drugs. RESULTS: Of 87 patients, 61 (70%) had used the recommended COX-2 inhibitor(s). Of the 61 users, 54 (89%) tolerated the drug(s) well and 7 (11%) reported adverse events. Three patients reporting adverse events were rechallenged with the responsible COX-2 inhibitor, and their results were found to be negative. CONCLUSIONS: Long-term use of COX-2 inhibitors was tolerated well by most patients with AI, and placebo-controlled oral provocation tests, as a single test, seemed to predict tolerability. Furthermore, self-reported positive reactions in the long-term should also be confirmed with rechallenge tests for definite diagnosis.     

How do gastric carcinoma classification systems relate to mucin expression patterns? An immunohistochemical analysis in a series of advanced gastric carcinomas

Gastric carcinoma classifications differ in their value for distinguishing tumors according to their morphological pattern, functional properties, and biological significance. In this study we evaluated which of three established classification systems is best correlated with the expression patterns of certain mucins. A total of 160 gastric carcinomas from Turkey and Germany were screened immunohistochemically for the expression of MUC1, MUC2, MUC5AC, and MUC6, and the results were related to the different tumor categories in Lauren's, Carneiro's, and Goseki's classifications. It was found that in all three classifications carcinomas belonging to the gland-forming category most commonly expressed MUC1: 78% of Goseki's grade I carcinomas, 81.1% of Lauren's intestinal type carcinomas, and 82.8% of Carneiro's glandular type. MUC2 was expressed in all Goseki grade II carcinomas, which comprise the mucinous type, while it was not significantly associated with any of the other classifications. MUC5AC was found in all Goseki grade IV carcinomas, i.e., signet ring cell carcinomas. It was also significantly associated with Carneiro's mixed type and isolated cell type carcinomas, while there was no correlation with any of Lauren's types. MUC6 failed to show a relationship with any of the categories of the various classifications. We conclude that Goseki's classification is best correlated with MUC expression patterns because it distinguishes clearly between MUC1-positive gland-forming carcinomas, MUC2-positive mucinous ones, and MUC5AC-positive signet ring cell carcinomas. It is likely that each of these gastric carcinoma types has its own carcinogenesis.     

The prevalence of fecal colonization of enterococci, the resistance of the isolates to ampicillin, vancomycin, and high-level aminoglycosides, and the clonal relationship among isolates

The gastrointestinal tract carriage of enterococci was searched in 150 hospitalized patients and 100 outpatients, and clonal relatedness of the isolates and their resistance to ampicillin, vancomycin, and high-level streptomycin and gentamicin were investigated. A stool sample or rectal swab collected from each patient was inoculated into appropriate media within an hour. Enterococcus species were identified by using conventional biochemical tests, API-20 Strep assay, and BBL crystal kit. Antibiotic susceptibility tests were performed using Kirby-Bauer disk diffusion method. A polymerase chain reaction (PCR) was used to detect vanA and vanB genes. Pulsed-field gel electrophoresis (PFGE) and arbitrarily primed-polymerase chain reaction (AP-PCR) methods were used for molecular typing of the strains. Enterococci were isolated from 90 (60%) of the specimens collected from 150 inpatients. Of these 90 isolates, 37 (41%) had high-level gentamicin resistance, 36 (40%) had high-level streptomycin resistance, and 50 (55.6%) had ampicillin resistance. Fecal colonization was found in 30% of the outpatients. Resistances to ampicillin, high-level streptomycin, and gentamicin were 13%, 10%, and 3%, in these patients' isolates, respectively. No vancomycin-resistant enterococci were detected by both agar diffusion and PCR assays in our study. Both typing procedures were applied on 78 Enterococcus strains isolated from inpatients. AP-PCR typing showed that 30 (50.8%) of the 59 E. faecium and 5 (50%) of the 10 E. faecalis strains were clonally related. These values were found to be 12 (20.3%) and two (20%) by PFGE, respectively. The typing procedures did not find any clustered strains in the six E. durans and three E. avium isolates. Neither PFGE nor AP-PCR result was significantly different among the sensitive and resistant strains. Our results indicate that the high prevalence of colonization with ampicillin and highlevel aminoglycoside-resistant enterococci is an important problem in our medical center. The high clonal diversity among the isolates indicates limited spread of antibiotic-resistant strains between patients.