M. Mahfuzur Rahman

Arsenic uptake by aquatic macrophyte Spirodela polyrhiza L.: Interactions with phosphate and iron

The uptake of arsenate (As(V)) and dimethylarsinic acid (DMAA) by aquatic macrophyte Spirodela polyrhiza L. was investigated to determine the influence of arsenic interaction with PO4(3-) and Fe ions. Plants were grown hydroponically on standard Murashige and Skoog (MS) culture solutions. Arsenic concentrations in Fe-oxide (Fe-plaque) on plant surfaces were determined by citrate-bicarbonate-ethylenediaminetetraacetic acid (CBE) technique. S. polyrhiza L. accumulated 51-fold arsenic from arsenate solution compared to that from DMAA solution with initial concentrations of 4.0 and 0.02microM of arsenic and phosphate, respectively. The arsenate uptake was negatively (p<0.001) correlated with phosphate uptake and positively (p<0.05) correlated with iron uptake. About 56% of the total arsenic was accumulated into the plant tissues while 44% was adsorbed on Fe-plaque (CBE-extract), when the plants were grown on arsenate solution. The DMAA uptake into the plant was neither affected by the phosphate concentrations nor correlated (p>0.05) with iron accumulation. The results suggest that adsorption of arsenate on Fe-plaque of the surface of S. polyrhiza L. contributes to the arsenic uptake significantly. Thus, arsenate uptake in S. polyrhiza L. occurred through the phosphate uptake pathway and by physico-chemical adsorption on Fe-plaques of plant surfaces as well. The S. polyrhiza L. uses different mechanisms for DMAA uptake.

Chitosan biopolymer promotes yield and stimulates accumulation of antioxidants in strawberry fruit

Strawberry is a well-known source of natural antioxidants with excellent free radical scavenging capacity. This study determined the effects of chitosan application in field condition on plant growth, fruit yield and antioxidant activities in strawberry fruit. Foliar applications of chitosan on strawberry significantly increased plant growth and fruit yield (up to 42% higher) compared to untreated control. Increased fruit yield was attributed to higher plant growth, individual fruit weight and total fruit weight/plant due to the chitosan application. Surprisingly, the fruit from plants sprayed with chitosan also had significantly higher contents (up to 2.6-fold) of carotenoids, anthocyanins, flavonoids and phenolics compared to untreated control. Total antioxidant activities in fruit of chitosan treated plants were also significantly higher (ca. 2-fold) (p< 0.05) than untreated control. To the best of our knowledge, this is the first report of chitosan applied on field plants providing significant improvement of both yield and health benefiting biochemical contents in strawberry fruit. Further study on the elucidation of mechanisms involved with enhancement of growth, yield and biochemical contents by chitosan is needed to promote sustainable production of strawberry.

Socio-demographic Characteristics and Mode of Traumatic Thoraco-Lumbar Spine Injuries at a Referral Tertiary Care Hospital in Bangladesh

Background: Traumatic thoraco-lumbar spine injuries occur in different ways during working. Objectives: The purpose of the present study was to find out the-demographic Characteristics and Mode of Traumatic Thoraco-Lumbar Spine Injuries. Methodology: This cross-sectional study was conducted at the National Institute of Traumatology and Orthopaedic Rehabilitation (NITOR), Dhaka, Bangladesh from July 2004 to June 2006 for a period of 2(two) years. Patients with diagnosed cases of traumatic thoraco-lumbar spinal injury with complete or incomplete cord lesion irrespective of sex were selected as study population. An elaborate history of the selected patient was taken with an emphasis of mechanism, time of injury, past history of illness. Result: A total number of 17 patients with thoracolumbar spine injury were recruited. Out of 17 patients, 7(41.2%) patients were in the age group of 21-30 years that is very younger age group. The mean age was 29.29 years. The male and female ratio was 4.7:1. In this series most affected people are farmer (47.05%). Most affected groups are injured by fall from height (70.58%) especially from tree and from roof of the buildings. Conclusion: Young age group male workers are most commonly affected in traumatic thoraco-lumbar spine injuries. [Journal of National Institute of Neurosciences Bangladesh, 2018;4(1): 51-53]

Surgical Management of Intestinal Tuberculosis in Preoperatively Unsuspected Cases at a Tertiary Care Hospital in Dhaka City

Background: Surgical management of intestinal tuberculosis is a crucial task in preoperatively unsuspected cases. Objective: The present study was undertaken to see the different surgical management of intestinal tuberculosis in preoperatively unsuspected cases. Methodology: This clinical trial was conducted in different units of the Department of Surgery at Dhaka Medical College Hospital, Dhaka from March 2002 to March 2004 for a period of two (2) years. Purposive sampling technique was applied to collect the study population. Patients with no suspicion about pulmonary as well as intestinal tuberculosis, history of cough & hemoptysis, no history of antitubercular drug taken, diagnosed as other than tuberculosis, per operative suspicion raised by any one or more of followings, enlarge lymph nodes in mesentery, omental masses, ileocaecal masses, suspicious growth in ileum, omental thickening, perforation suspected by tuberculosis were selected as study population. Biopsy was taken from suspicious lesions. Histopathology was confirmed the granulomatous lesion. Results: A total number of 300 patients were undergone surgical intervention of which 38(12.7%) cases. Maximum affected age group was 21 to 30 years which was 16(42%) cases. Granulomatous inflammation was found in 12(31.6%) cases. Maximum mode of presentation was in the form of emergency which was 36(94.7%) cases. Tissue was taken for biopsy from mesenteric lymph node in 16(42.10%) cases. Procedures done during laparotomy were resection of ileum and ileoileal anastomosis and proximal ileostomy which was performed in 6(23.07%) cases, resection of ileum and ileostomy in 5(19.23%) cases and resection of ileum with ileoileal anastomosis in 3(11.53%) cases. Conclusion: In conclusion surgical management is performed by resection of jejunum with jejunojejunal anastomosis, hemicolectomy with ileotrasverse anastomosis and resection of ileum with ileostomy.