Field and laboratory investigations of budding in the tetillid sponge Cinachyrella cavernosa

The budding process of the tetillid sponge Cinachyrella cavernosa was studied for one year in the low intertidal zone near Mhapan (15°55′27.48″N, 73°33′29.89″E), on the central west coast of India. The sponges showed the highest budding frequency when the average water temperature of intertidal rock pools was 32.4±0.23°C (February–March), followed by a significant decrease in budding frequency at 28.2±0.12°C (April–July), and no budding at ≤25.9±0.12°C (August–November). Stepwise multiple regression analysis of physico‐chemical factors revealed temperature as the most prominent factor regulating the intensity of budding. Based on size and morphology, three stages of sponge buds were defined. The production of buds was found to be asynchronous, as adult sponges possessed buds of all three stages. Differences among these stages were examined at ultrastructural (in terms of spicules) and molecular (in terms of RNA/DNA) levels. Stage I (<0.5 mm dia‐meter) buds showed a complete absence of microscleres (sigmaspires), whereas stage II (0.5–1 mm) and stage III (>1 mm) buds contained all spicules characteristic of the adult sponge. There was a significant increase in RNA/DNA ratio from stage I to III, suggestive of a progressive increase in physiological activity during the developmental process. Additionally, we studied post‐settlement bud growth under field and laboratory conditions. Newly settled buds displayed a lower average‐specific growth rate in the field, owing to variability in environmental conditions, but more rapid growth under controlled conditions in the laboratory. This study highlights the role of abiotic factors in regulating the budding process and stresses the ecological significance of budding in maintaining natural sponge populations. Our data suggest that an increased frequency of budding under stressful conditions, such as high temperature, is an advantageous adaptation for these sponges. Buds showed rapid development, as no metamorphosis is involved, and retained the genotype of the parents, yielding high reproductive outputs and survival rates.     

Brucella abortus bacA mutant induces greater pro-inflammatory cytokines than the wild-type parent strain

The inner-membrane protein BacA affects Brucella LPS structure. A bacA deletion mutant of Brucella abortus, known as KL7 (bacA(mut)-KL7), is attenuated in BALB/c mice and protects against challenge. Thus, bacA mutation was a candidate for incorporation into live attenuated vaccines. We assessed bacA(mut)-KL7 in 2 additional mouse strains: the more resistant C57BL/6 that produces interferon-gamma throughout the infection and the highly susceptible interferon-gamma-deficient C57BL/6 in which brucellae exhibit continual exponential growth. While it was hypothesized that bacA(mut)-KL7 would exhibit even greater attenuation relative to its parent strain B. abortus 2308 in C57BL/6 mice than it did in BALB/c mice, this was not the case. Moreover, it was more pathogenic in C57BL/6 interferon-gamma-deficient mice than 2308 causing abscesses and wasting even though the splenic loads of bacA(mut)-KL7 were significantly lower. These 2 observations were correlated, respectively, with an ability of IFNgamma-activated macrophages to equivalently control strains 2308 and bacA(mut)-KL7 and the ability of bacA(mut)-KL7 organism and its LPS to induce greater amounts of pro-inflammatory cytokines than 2308. We conclude that attenuation properties of bacA mutation are dependent upon the nature of the host but more importantly that bacterial gene deletion can result in increased host pathology without an increase in bacterial load, crucial considerations for vaccine design.     

Chronic spinal cord injury impairs primary antibody responses but spares existing humoral immunity in mice

Spinal cord injury (SCI) results in immune depression. To better understand how injury inhibits humoral immunity, the effects of chronic thoracic SCI on B cell development and immune responses to thymus-independent type 2 and thymus-dependent Ags were determined. Mice received complete crush injury or control laminectomy at either thoracic level 3, which disrupts descending autonomic control of the spleen, or at thoracic level 9, which conserves most splenic sympathetic activity. Although mature B cell numbers were only mildly reduced, bone marrow B cell production was transiently but profoundly depressed immediately after injury. Despite the return of normal B cell production 4 wk after SCI, mice receiving thoracic level 3 injury showed a significant reduction in their ability to mount primary thymus-independent type 2 or thymus-dependent immune responses. The latter were marked by decreases in germinal center B cells as well as class-switched high-affinity Ab-secreting cells. Importantly, injury did not affect affinity maturation per se, pre-existing B cell memory, or secondary humoral immune responses. Taken together, these findings show that chronic high thoracic SCI impairs the ability to mount optimal Ab responses to new antigenic challenges, but spares previously established humoral immunity.     

Investigations of scutellum derived calli,cues from size,effective ionic strength of synthetic media and improved regeneration capacity for indica rice

Scutellum derived calli of recalcitrant indica rice variety ASD-16 are subjected to qualitative and quantitative changes using different callus induction media (CIM). The suitable media for generation of regenerating calli by evaluating the increase in size of these calli as a function of time (Meazure^TM2.0 software), were recorded (till 25-days post-inoculation). After 10-days post-inoculation significant differences which ranged from 5 mm to 6.5 mm and 30% variation in calliQuery size were recorded for different CIM. Improved regeneration achieved by reducing the time on callusing media to 5-days and 10-days. Also, the insights are provided for the role of cationic and anionic strength, phenomics of somatic embryogenesis, and also browning of the calli for recalcitrant indica rice variety ASD-16. The statistical analysis of size of calli with ionic strength of cations K⁺, H⁺, NH₄⁺, Mg²⁺, Ca²⁺ and anions PO₄^3?, NO₃^?, Cl^? (statistical analysis tool “The Unscramble X”) shows positive correlation. The loss of scutellum derived calli due to browning was reduced by allowing the mature seed used for generation of calli to be attached to the growing calli. The browning of the calli was monitored in different media for the pattern, and statistical evidences are provided for the important role played by ionic ratios of media constituent namely, NH₄⁺/NO₃^? and SO₄^2?/PO₄^3? (reported here for the first time). Maximum healthy calli obtained (80%) were on CIM-2 whereas maximal browning (60%) was obtained on CIM-4 after 15-days post-inoculation. Successful regeneration is achieved for recalcitrant indica rice variety ASD-16.

     

Evidences for differential expression of miR167d-5p,target, positional nucleotide preference,and its role in somatic and different stages of regenerating calli of Oryza sativa

Plant Cell, Tissue and Organ Culture (PCTOC) - The incorporation of important value-added features in rice by Agrobacterium-mediated transformation of scutellum-derived calli is an established...     

Association of 25 bp deletion in MYBPC3 gene with left ventricle dysfunction in coronary artery disease patients

Rationale

Mutations in MYBPC3 encoding cardiac myosin binding protein C are common genetic cause of hereditary cardiac myopathies. An intronic 25-bp deletion in MYBPC3 at 3′ region is associated with dilated (DCM) and hypertrophic (HCM) cardiomyopathies in Southeast Asia. However, the frequency of MYBPC3 25 bp deletion and associated clinical presentation has not been established in an unrelated cohort of left ventricular dysfunction (LVD) secondary to coronary artery disease (CAD) patients.

Objective

We sought to determine the role of MYBPC3 25 bp polymorphism on LVD in two cohorts of CAD patients.

Methods and Results

The study included 265 consecutive patients with angiographically confirmed CAD and 220 controls. MYBPC3 25 bp polymorphism was determined by polymerase chain reaction. Our results showed that carrier status of MYBPC3 25 bp deletion was associated with significant compromised left ventricle ejection fraction (LVEF ≤45) in CAD patients (p value  =  <0.001; OR = 4.49). To validate our results, we performed a replication study in additional 140 cases with similar clinical characteristics and results again confirmed consistent findings (p = 0.029; OR = 3.3). Also, presence of the gene deletion did not have significant association in CAD patients with preserved ejection fraction (LVEF>45) (p value  = 0.1; OR  = 2.3).

Conclusion

The frequency of MYBPC3 DW genotype and D allele was associated with compromised LVEF implying that genetic variants of MYBPC3 encoding mutant structural sarcomere protein could increase susceptibility to left ventricular dysfunction. Therefore, 25 bp deletion in MYBPC3 may represent a genetic marker for cardiac failure in CAD patients from Southeast Asia.