Bhaskar Bhattacharjee | Tripura University (original) (raw)

Uploads

Papers by Bhaskar Bhattacharjee

Chemotherapy for leukemia has severe toxicity and bone marrow transplantation is both financially... more Chemotherapy for leukemia has severe toxicity and bone marrow transplantation is both financially and logistically demanding. Therefore, immunotherapy is a feasible and promising approach to treat leukemia. For immunotherapy, cytotoxic T lymphocytes (CTL) against leukemic cells were induced. In BALB/c mice, leukemia was induced by N-ethyl-N′-nitrosourea (ENU). The mice were treated with recombinant IL-3 and GM-CSF – both 5 μg/kg/day for four days to induce functional CTL. The IL-3+GM-CSF treatment increased total leukocyte counts, accompanied by significant increase in CTL activity, in the leukemic mice. The IL-3+GM-CSF treatment also enhanced the expression of both p40 and p35 isoforms of IL-12. Perforin and granzyme B expressions were increased in the treated group supporting the T lymphocyte-mediated cytotoxic killing of the target cells. The protein tyrosine kinase (PTK) activity was increased in leukemia but decreased after the treatment with IL-3 and GM-CSF. Interferon gamma (IFN-γ) production was decreased in leukemic condition but increased after the treatment with these colony stimulating factors. These data indicate the anti-leukemic potential of the IL-3 and GM-CSF combination therapy.

Objectives: Murine macrophages were playing a key role against microbes and foreign particles as ... more Objectives: Murine macrophages were playing a key role against microbes and foreign particles as well as help in solid tumorigenesis in the host body. In this experiment we were trying to evaluate the protein tyrosine kinase (PTK) activity in macrophages from experimentally induced leukemic animal model.
Methods: Balb/C mice were divided into four groups, two groups were challenged with N-N’ ethyl nitrosourea (ENU) and two groups remained without ENU challenged condition. After confirmation of leukemia induction, one normal and one ENU challenged groups were received rmIL-3 and rmGM-CSF in combination for 4 consecutive days. Disease was confirmed by histological studies of peripheral blood and bone marrow smear. PTK activity assay were done using universal tyrosine kinase assay kit.
Results: Protein tyrosine kinase (PTK) activity of macrophages was increased in leukemic animal significantly which were reduced after combination of IL-3 and GM-CSF treatment. IFN-γ level in blood serum was increased in leukemic mice and reinstates after treatment.
Conclusion: Results suggest that, in leukemia reduced macrophage number can be increased by IL-3 and GM-CSF administration in combination but PTK activity is not involved to increase the number of macrophages. PTK activity may be involved in macrophage activation process in leukemic animal.
Keywords: Macrophages, protein tyrosine kinase, interferon- γ, leukemia, N-N’ ethyl nitrosourea, cytokines, interleukin-3, granulocyte-macrophage colony stimulating factor

Aim: The enrolment of blood progenitor cells from the bone marrow into peripheral blood or mobili... more Aim: The enrolment of blood progenitor cells from the bone marrow into peripheral blood or mobilization is required in leukemia following treatment with chemotherapy and/or cytokines. In this experiment, we examined the mobilization of lymphocytes from bone marrow to peripheral blood using interleukin-3 (IL-3) and granulocyte monocyte-colony stimulating factor (GM-CSF) in
experimentally induced leukemia model.
Methods: In our Laboratory, leukemia is induced in Balb/C mice by challenging with N’-N’ Ethylnitrosourea (ENU) at the dose of
80mg/kg body twice in one week interval and confirmed by staining of peripheral blood and bone marrow smear. After confirmation of leukemia induction, animals were received rmIL-3 and rmGM-CSF in combination for consecutive four days. Leishman’s staining of peripheral blood smear and isolation of lymphocytes by percoll gradient method used in this study to determine the
cell count.
Results: Total leukocyte count exhibits 6 folds higher in number in leukemia group compared to control group. After combination of treatment the total leukocyte count was same as leukemic control group until the sacrifice of animals. But the lymphocyte count increased around 2.6 fold after combination of IL-3 and GM-CSF treatment to leukemic mice.
Conclusion: This data suggests the mobilization of lymphocytes from bone marrow to peripheral blood may be immunologically
beneficial to combat against tumor cells.

Key Words: Mobilization, Leukemia, ENU, interleukin-3, Granulocyte monocyte colony, Stimulating factor
Abbreviations: ENU: N-ethyl-N’-nitrosourea, rmIL-3: recombinant mouse Interleukin-3, rmGM-CSF: recombinant mouse
Granulocyte-Macrophage Colony-Stimulating Factor, CD-8: Cluster of Differentiation 8, CD-4: Cluster of Differentiation 4, HSC:Haematopoetic stem cells, CTL: Cytotoxic T Lymphocytes.

Protein tyrosine kinase (PTK) is an enzyme which mediates cell function, growth, metabolism and a... more Protein tyrosine kinase (PTK) is an enzyme which mediates cell function, growth, metabolism and apoptosis. The present work has an objective to evaluate the involvement of PTK activity on neutrophil population in the peripheral blood upon stimulation with G-CSF plus IL-15 in leukemic animal. N-N’-Ethyl-nitrosourea (ENU), a carcinogen was used to induce leukemia in BALB/C mice where in combination with Granulocyte colony stimulating factor (G-CSF) and Interleukin-15 (IL-15) were treated. To determine the PTK activity in normal and leukemic animal universal tyrosine kinase assay kit were used. Appearance of blast cells in peripheral blood and bone marrow smear confirmed the leukemia. Neutrophils were isolated from spleen using percoll gradient method. Cell population was measured in both normal and leukemic animal before and after treatment of combination of cytokines. ENU induced mice model showed mixed type leukemia dominating lymphoblastic in nature. The data indicated that treatment with IL-15 and G-CSF in combination to leukemic mice, increased the number of neutrophil population in periphery and under the regulated control of protein tyrosine kinase activity. Results may hint for cell based therapeutic approach to improve neutrophil population in leukemia.

ABSTRACT Context: Ichnocarpus frutescens (Linn) (Family-Apocynaceae) is an evergreen plant and th... more ABSTRACT
Context: Ichnocarpus frutescens (Linn) (Family-Apocynaceae) is an evergreen plant and this plant is used in traditional Indian medicine for centuries to treat several illness including fever, dyspepsia, skin troubles and headache. The possible antitumor activity and antioxidant role of I. frutescens in the mice transplanted with Ehrlich ascites carcinoma (EAC) was reported. Objectives: We have evaluated the antimicrobial activity, in vitro biochemical antioxidant activity (viz. superoxide radical scavenging activity, DPPH radical scavenging assay) and in vitro biochemical antidiabetic activity (viz. α-glucosidase inhibitory assay) of the ethyl acetate extract of I. frutescens roots. Results: The root extract of the plant exhibited potential antibacterial activity against, Shigella flexneri 16 (gram negative), Shigella dysenteriae 1 (gram negative), Vibrio cholerae non 0139(L4) (gram negative), Vibrio cholerae non0139(CSK6669) (gram negative), Streptococcus pneumoniae (gram positive) and Escherichia coli (gram negative). The extract also showed significant inhibitory activity of α-glucosidase enzyme compared to acarbose (positive control) which indirectly indicated antidiabetic activity. The extract had potent superoxide radical scavenging activity compared to butylated hydroxyanisole (BHA). Conclusion: These results indicate that this plant may have phytochemicals of potential antibacterial, antioxidant and antidiabetic activities.
Keywords: Ichnocarpus frutescens, antibacterial, antidiabetic, antioxidant, superoxide, α-glucosidase, acarbose, butylated hydroxyanisole.

ABSTRACT Objective: The present investigation is carried out to assess in vitro antimicrobial, an... more ABSTRACT
Objective: The present investigation is carried out to assess in vitro antimicrobial, antioxidant and anti-alphaglucosidase activity of the crude and fraction extracts of both leaf and fruits of the plant Dillenia pentagyna Roxb. (Dilleniaceae).
Methods: Extracts prepared from leaf and fruits by drying and fractionation process. Antibacterial activity assessed by disc diffusion and liquid culture method. Antioxidant activity was assayed by superoxide radical scavenging capability and by DPPH scavenging capability. By using the enzyme α-glucosidase and substrate p-nitrophenyl glucopyranoside (pNPG), the inhibitory activity of the extracts was assayed.
Results: Crude extracts of fruits from both butanol fraction and chloroform fraction showed promising antibacterial activity in disc diffusion method through measuring inhibition zone. Both butanol and chloroform fraction showed a significant superoxide radical scavenging activity and using DPPH (1,1-diphenyl-2-picryl hydrazyl), butanol fraction extract of fruit showed a significant scavenging property. α-glucosidase (E.C No. 3.2.1.20) enzyme activity is inhibited significantly by the leaf extract of the plant.
Conclusion: The results suggest that the crude plant extract contain some compounds which have antimicrobial activity, more potent antioxidant activity as well as α-glucosidase inhibitory activity.
Keywords: Dillenia pentagyna, antimicrobial, antioxidant, antidiabetic, superoxide, α-glucosidase, DPPH.

The extract of the plant, Artocarpus chaplasa, (family Moraceae; Local name: Chamal) is used as t... more The extract of the plant, Artocarpus chaplasa, (family Moraceae; Local name: Chamal) is used
as traditional medicine for treatment of various ailments and skin diseases in north eastern India. The
antimicrobial, antioxidant and antidiabetic properties of the crude stem bark methanol extract of the
plant have been evaluated. The extract showed antimicrobial activity against Shigella dysentariae 1,
Klebsiella pneumonia, Vibrio cholerae non.0139 (L4), Vibrio cholerae non.0139 (CSK6669), E. coli,
Staphylococcus aureus and Streptococcus pneumoniae strain with inhibition zone diameter of 10mm,
8.66mm, 8.66mm, 9.66mm, 9.66mm, 8.66mm and 9.66mm respectively at highest concentration of
1mg/disc. It also showed superoxide radical scavenging activity in a dose dependent manner with
highest inhibition of 63.2% at 200μg/ml compared to positive control BHA having 46.4% inhibition.
It exhibited significant DPPH reduction with inhibition of 71.1% at 10μg/ml. On a-glucosidase
inhibitory assay, the extract (100μg/ml) showed 85.3% inhibition compared with positive control
acarbose (84.723%).

Context: The genus Mussaenda (Rubiaceae) includes 200 species distributed in hilly tracks of nort... more Context: The genus Mussaenda (Rubiaceae) includes 200 species distributed in hilly tracks of north eastern India and in tropics of the old world. Mussaenda roxburghii Hook. f. mainly grown in Tripura and other north eastern states of India has been used as traditional medicine. Objectives: The objective of this study was to evaluate in vitro antimicrobial, antioxidant and anti-α-glucosidase activities of the leaves extract from Mussaenda roxburghii. Methods: Antimicrobial assay was done by disc diffusion technique using six human pathogenic bacteria, Shigella dysenteriae 1, Vibrio cholerae non.0139(L4), Vibrio cholerae non.0139(CSK6669), Streptococcus pneumoniae, Staphylococcus aureus and Escherichia coli. In vitro antioxidant potential was studied using DPPH (1,1-diphenyl-2-picryl hydrazyl) and superoxide radical scavenging property with Butylated Hydroxy Anisole (BHA) and Ascorbic acid as positive control, respectively. In vitro α-glucosidase (E.C No.3.2.1.20) inhibitory activity was determined using Acarbose as positive control. Results: Among the two fractions, maximum antimicrobial activity was against V. cholerae non.0139(CSK6669) at 500 µg/disc with n-butanol fraction and with chloroform fraction it was against S. aureus and E. coli at 1 mg/disc concentration. At 100µg/ml concentration both n-butanol and chloroform fractions showed significant antioxidant activity against DPPH and superoxide radicals. Both the fractions also exhibited moderate inhibition of α-glucosidase activity at 500 µg/ml of n-butanol fraction and 250 µg/ml of chloroform fraction. W WO OR RL LD D J JO OU UR RN NA AL L O OF F P PH HA AR RM MA AC CY Y A AN ND D P PH HA AR RM MA AC CE EU UT TI IC CA AL L S SC CI IE EN NC CE ES S V Vo ol lu um me e 2 2, , I Is ss su ue e 5 5, , 3 32 21 16 6--3 32 22 28 8. . R Re es se ea ar rc ch h A Ar rt ti ic cl le e I