Priti Prasanna Maity | IIT Kharagpur (original) (raw)

Uploads

Papers by Priti Prasanna Maity

Wound healing management is a major challenge for critical full-thickness skin wounds.

Wound healing is a dynamic process wherein cells, and macromolecules work in consonance to facili... more Wound healing is a dynamic process wherein cells, and macromolecules work in consonance to facilitate tissue regeneration and restore tissue integrity. In the case of fullthickness (FT) wounds, healing requires additional support from native or synthetic matrices to aid tissue regeneration. In particular, a matrix with optimum hydrophilic-hydrophobic balance which will undergo adequate swelling as well as reduce bacterial adhesion has remained elusive. In the present study, Polyurethane Diol Dispersion (PUD) and the antibacterial Chitosan (Chn) were blended in different ratios which self-organized to form macroporous hydrogel scaffolds (MHS) at room temperature on drying. SEM and AFM micrographs revealed the macroporosity on top and fracture surfaces of the MHS. FTIR spectra revealed the intermolecular as well as intra-molecular hydrogen bonding interactions between the two polymers responsible for phase separation, which was also observed by micrographs of blend solutions during the drying process. The effect of phase separation on mechanical properties and in vitro degradation (hydrolytic, enzymatic and pH dependent) of MHS were studied and found to be suitable for wound healing. In vitro cytocompatibility was demonstrated by the proliferation of primary rat fibroblast cells on MHS. Selected MHS was subjected to in vivo FT wound healing study in Wistar rats and compared with an analogous polyurethane containing commercial dressing i.e. Tegaderm TM . The MHS -treated wounds demonstrated accelerated healing with increased wound contraction, higher collagen synthesis, and vascularization in wound area compared to Tegaderm TM . Thus, it is concluded that the developed MHS is a promising candidate for application as FT wound healing dressings.

The potentiality of collagen sponge as a skin substitute, derived from mrigal (Cirrhinus cirrhosu... more The potentiality of collagen sponge as a skin substitute, derived from mrigal (Cirrhinus cirrhosus) scale has been explored in this study. Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) from the scale of mrigal were isolated and characterized. The yields of ASC and PSC were ∼3% and ∼7% based on the dry weight of scale while the hydroxyproline content was ∼90 mg/g. Scanning electron microscope revealed progressive demineralization with EDTA on time dependent scale. Further, the D-Spacing in fibril bundles were calculated to be ∼67 nm. Fourier transform infrared and circular dichroism spectra confirmed extracted protein to be collagen I, where both ASC and PSC comprised of two different-chains (1 and 2). The denaturation temperature (T d) of the collagen solution was 35 • C closer to T d of mammalian collagen. In vitro cell culture studies on the extracted collagen sponge showed efficient cell growth and proliferation. Additionally, co-culture with fibroblast and keratinocyte cells showed development of stratified epidermal layer in vitro. Faster wound healing potential of the extracted collagen in a rat model proved its applicability as a dermal substitute.

Osteochondral injuries are challenging to repair due to their complex tissue anatomy and restrict... more Osteochondral injuries are challenging to repair due to their complex tissue anatomy and restricted self-repairing ability associated with a limited blood supply. Osteochondral tissue engineering is an important clinical aspect of the management and treatment of cartilage and underlying bone. In the present study, we fabricated human placenta-derived extracellular matrix sponges (PEMS) for repair of osteochondral tissue through a decellularization process. There were no significant cellular components present in the PEMS; hematoxylin & eosin/DAPI staining, DNA quantification and agarose gel electrophoresis were used to evaluate the extent of decellularization. Moreover, no significant alteration to the collagen and glycosaminoglycan (native extracellular matrix) content of the PEMS was observed. PEMS in vitro provided a non-cytotoxic environment rich in bioactive cues for human amniotic membrane-derived stem cells (HAMSCs) to proliferate in and differentiate into chondrogenic and osteogenic lineages under induction. Histological analysis at 28 days after the PEMS were subcutaneously implanted demonstrated no severe immune response in the host and supported the formation of blood vessels. To assess the osteochondral tissue repair ability of PEMS, cell-free PEMS (CFP) and cell-seeded PEMS (CSP) were implanted at osteochondral defect sites in a rabbit model. Histological scores indicated that osteochondral regeneration was more successful in the defects filled with CSP compared to those filled with CFP and empty defects (ED) after 60 days of implantation. In summary, a naturally derived biocompatible scaffold composed of extracellular matrix from human placenta has been successfully developed for osteochondral tissue engineering.

Most polymeric nanofibers used for bone tissue engineering lack adequate functional groups for bi... more Most polymeric nanofibers used for bone tissue engineering lack adequate functional groups for bioactivity. This study explores the potential of nanofibers of phosphate functionalized derivative of chitosan-N-methylene phosphonic chitosan (NMPC) for bone tissue engineering. Nanofibers were fabricated by electrospinning of NMPC/PVA blend solutions. NMPC/PVA nanofibers exhibited 172% higher viability of MG-63 cells compared to pure PVA nanofibers. ALP and Collagen type I genes revealed higher expression in NMPC nanofibers on day 3 whereas osteocalcin gene was expressed on day 7. In rabbit tibial defects, NMPC based electrospun graft showed presence of no adverse tissue reaction by histological examination while radiological examination suggested acceleration of bone healing by 300% compared to defects without any scaffold. Thus it is concluded NMPC based nanofibers may have potential for bone grafting applications.

Purpose: Benign phyllodes and fibroadenoma are two well-known breast tumors with remarkable diagn... more Purpose: Benign phyllodes and fibroadenoma are two well-known breast tumors with remarkable diagnostic
ambiguity. The present study is aimed at determining an optimum set of immuno-histochemical
features to distinguish them by analyzing important observations on expressions of important genes in
fibro-glandular tissue.
Methods: Immuno-histochemically, the expressions of p63 and -SMA in myoepithelial cells and collagen
I, III and CD105 in stroma of tumors and their normal counterpart were studied. Semi-quantified features
were analyzed primarily by ANOVA and ranked through F-scores for understanding relative importance
of group of features in discriminating three classes followed by reduction in F-score arranged feature
space dimension and application of inter-class Bhattacharyya distances to distinguish tumors with an
optimum set of features.
Results: Among thirteen studied features except one all differed significantly in three study classes.
F-Ranking of features revealed highest discriminative potential of collagen III (initial region). F-Score
arranged feature space dimension and application of Bhattacharyya distance gave rise to a feature set of
lower dimension which can discriminate benign phyllodes and fibroadenoma effectively.
Conclusions: The work definitely separated normal breast, fibroadenoma and benign phyllodes, through
an optimal set of immuno-histochemical features which are not only useful to address diagnostic ambiguity
of the tumors but also to spell about malignant potentiality.

Abstract: Method and system for analyzing breast carcinoma using microscopic image analysis of fi... more Abstract: Method and system for analyzing breast carcinoma using microscopic image analysis of fine needle aspirates. The method includes extracting a G-plane image from an image. The method also includes de-noising the G-plane image. Further, the method includes balancing histogram imbalance associated with the G-plane image. Furthermore, the method includes generating a binary image from the G-plane image. The method also includes filtering the binary image to yield a nuclear map. Further, the method includes extracting a nuclear contour from the nuclear map. Moreover, the method includes determining one or more parameters from at least one of the G-plane image, the nuclear map and the nuclear contour to enable detection of the breast lesion as one of malignant and non-malignant.

"Abstract- Tn pathology, phyllodes and fibroadenoma of breast are two well-known tumors with dif... more "Abstract- Tn pathology, phyllodes and fibroadenoma of breast are
two well-known tumors with differential malignant potentialities
and aetio-patllOlogy. But diagnostic ambiguity prevails, particularly
in the condition of stromal hyper-cellularity. To address such
classification problem, current study evaluated fresh breast tumor
biopsies in respect to expression of some candidate genes by
immunohistochemistry (THC) and structurally by swept sourceoptical
coherence tomography (SS-OCT). The THC assessed the
expression of p63 and a-SMA in myoepithelial cells (MECs) and
collagen T and TTl in stroma. Through skin SS-OCT, the crosssectional
structural features were noted non-invasively. Tn
phyllodes, expressions of P63 and a-SMA were less in comparison
to fibroadenoma and their normal counterpart whereas it was just
reverse for collagen T and III. The OCT images demonstrated
differential optical features of the biopsies in terms of presence of
foaminess in phyllodes in contrast to compactness of fibroadenoma.
Thus, the current study identified differential structural and
molecular signatures in these tumors, to address the diagnostic
ambiguities."

Wound healing management is a major challenge for critical full-thickness skin wounds.

Wound healing is a dynamic process wherein cells, and macromolecules work in consonance to facili... more Wound healing is a dynamic process wherein cells, and macromolecules work in consonance to facilitate tissue regeneration and restore tissue integrity. In the case of fullthickness (FT) wounds, healing requires additional support from native or synthetic matrices to aid tissue regeneration. In particular, a matrix with optimum hydrophilic-hydrophobic balance which will undergo adequate swelling as well as reduce bacterial adhesion has remained elusive. In the present study, Polyurethane Diol Dispersion (PUD) and the antibacterial Chitosan (Chn) were blended in different ratios which self-organized to form macroporous hydrogel scaffolds (MHS) at room temperature on drying. SEM and AFM micrographs revealed the macroporosity on top and fracture surfaces of the MHS. FTIR spectra revealed the intermolecular as well as intra-molecular hydrogen bonding interactions between the two polymers responsible for phase separation, which was also observed by micrographs of blend solutions during the drying process. The effect of phase separation on mechanical properties and in vitro degradation (hydrolytic, enzymatic and pH dependent) of MHS were studied and found to be suitable for wound healing. In vitro cytocompatibility was demonstrated by the proliferation of primary rat fibroblast cells on MHS. Selected MHS was subjected to in vivo FT wound healing study in Wistar rats and compared with an analogous polyurethane containing commercial dressing i.e. Tegaderm TM . The MHS -treated wounds demonstrated accelerated healing with increased wound contraction, higher collagen synthesis, and vascularization in wound area compared to Tegaderm TM . Thus, it is concluded that the developed MHS is a promising candidate for application as FT wound healing dressings.

The potentiality of collagen sponge as a skin substitute, derived from mrigal (Cirrhinus cirrhosu... more The potentiality of collagen sponge as a skin substitute, derived from mrigal (Cirrhinus cirrhosus) scale has been explored in this study. Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) from the scale of mrigal were isolated and characterized. The yields of ASC and PSC were ∼3% and ∼7% based on the dry weight of scale while the hydroxyproline content was ∼90 mg/g. Scanning electron microscope revealed progressive demineralization with EDTA on time dependent scale. Further, the D-Spacing in fibril bundles were calculated to be ∼67 nm. Fourier transform infrared and circular dichroism spectra confirmed extracted protein to be collagen I, where both ASC and PSC comprised of two different-chains (1 and 2). The denaturation temperature (T d) of the collagen solution was 35 • C closer to T d of mammalian collagen. In vitro cell culture studies on the extracted collagen sponge showed efficient cell growth and proliferation. Additionally, co-culture with fibroblast and keratinocyte cells showed development of stratified epidermal layer in vitro. Faster wound healing potential of the extracted collagen in a rat model proved its applicability as a dermal substitute.

Osteochondral injuries are challenging to repair due to their complex tissue anatomy and restrict... more Osteochondral injuries are challenging to repair due to their complex tissue anatomy and restricted self-repairing ability associated with a limited blood supply. Osteochondral tissue engineering is an important clinical aspect of the management and treatment of cartilage and underlying bone. In the present study, we fabricated human placenta-derived extracellular matrix sponges (PEMS) for repair of osteochondral tissue through a decellularization process. There were no significant cellular components present in the PEMS; hematoxylin & eosin/DAPI staining, DNA quantification and agarose gel electrophoresis were used to evaluate the extent of decellularization. Moreover, no significant alteration to the collagen and glycosaminoglycan (native extracellular matrix) content of the PEMS was observed. PEMS in vitro provided a non-cytotoxic environment rich in bioactive cues for human amniotic membrane-derived stem cells (HAMSCs) to proliferate in and differentiate into chondrogenic and osteogenic lineages under induction. Histological analysis at 28 days after the PEMS were subcutaneously implanted demonstrated no severe immune response in the host and supported the formation of blood vessels. To assess the osteochondral tissue repair ability of PEMS, cell-free PEMS (CFP) and cell-seeded PEMS (CSP) were implanted at osteochondral defect sites in a rabbit model. Histological scores indicated that osteochondral regeneration was more successful in the defects filled with CSP compared to those filled with CFP and empty defects (ED) after 60 days of implantation. In summary, a naturally derived biocompatible scaffold composed of extracellular matrix from human placenta has been successfully developed for osteochondral tissue engineering.

Most polymeric nanofibers used for bone tissue engineering lack adequate functional groups for bi... more Most polymeric nanofibers used for bone tissue engineering lack adequate functional groups for bioactivity. This study explores the potential of nanofibers of phosphate functionalized derivative of chitosan-N-methylene phosphonic chitosan (NMPC) for bone tissue engineering. Nanofibers were fabricated by electrospinning of NMPC/PVA blend solutions. NMPC/PVA nanofibers exhibited 172% higher viability of MG-63 cells compared to pure PVA nanofibers. ALP and Collagen type I genes revealed higher expression in NMPC nanofibers on day 3 whereas osteocalcin gene was expressed on day 7. In rabbit tibial defects, NMPC based electrospun graft showed presence of no adverse tissue reaction by histological examination while radiological examination suggested acceleration of bone healing by 300% compared to defects without any scaffold. Thus it is concluded NMPC based nanofibers may have potential for bone grafting applications.

Purpose: Benign phyllodes and fibroadenoma are two well-known breast tumors with remarkable diagn... more Purpose: Benign phyllodes and fibroadenoma are two well-known breast tumors with remarkable diagnostic
ambiguity. The present study is aimed at determining an optimum set of immuno-histochemical
features to distinguish them by analyzing important observations on expressions of important genes in
fibro-glandular tissue.
Methods: Immuno-histochemically, the expressions of p63 and -SMA in myoepithelial cells and collagen
I, III and CD105 in stroma of tumors and their normal counterpart were studied. Semi-quantified features
were analyzed primarily by ANOVA and ranked through F-scores for understanding relative importance
of group of features in discriminating three classes followed by reduction in F-score arranged feature
space dimension and application of inter-class Bhattacharyya distances to distinguish tumors with an
optimum set of features.
Results: Among thirteen studied features except one all differed significantly in three study classes.
F-Ranking of features revealed highest discriminative potential of collagen III (initial region). F-Score
arranged feature space dimension and application of Bhattacharyya distance gave rise to a feature set of
lower dimension which can discriminate benign phyllodes and fibroadenoma effectively.
Conclusions: The work definitely separated normal breast, fibroadenoma and benign phyllodes, through
an optimal set of immuno-histochemical features which are not only useful to address diagnostic ambiguity
of the tumors but also to spell about malignant potentiality.

Abstract: Method and system for analyzing breast carcinoma using microscopic image analysis of fi... more Abstract: Method and system for analyzing breast carcinoma using microscopic image analysis of fine needle aspirates. The method includes extracting a G-plane image from an image. The method also includes de-noising the G-plane image. Further, the method includes balancing histogram imbalance associated with the G-plane image. Furthermore, the method includes generating a binary image from the G-plane image. The method also includes filtering the binary image to yield a nuclear map. Further, the method includes extracting a nuclear contour from the nuclear map. Moreover, the method includes determining one or more parameters from at least one of the G-plane image, the nuclear map and the nuclear contour to enable detection of the breast lesion as one of malignant and non-malignant.

"Abstract- Tn pathology, phyllodes and fibroadenoma of breast are two well-known tumors with dif... more "Abstract- Tn pathology, phyllodes and fibroadenoma of breast are
two well-known tumors with differential malignant potentialities
and aetio-patllOlogy. But diagnostic ambiguity prevails, particularly
in the condition of stromal hyper-cellularity. To address such
classification problem, current study evaluated fresh breast tumor
biopsies in respect to expression of some candidate genes by
immunohistochemistry (THC) and structurally by swept sourceoptical
coherence tomography (SS-OCT). The THC assessed the
expression of p63 and a-SMA in myoepithelial cells (MECs) and
collagen T and TTl in stroma. Through skin SS-OCT, the crosssectional
structural features were noted non-invasively. Tn
phyllodes, expressions of P63 and a-SMA were less in comparison
to fibroadenoma and their normal counterpart whereas it was just
reverse for collagen T and III. The OCT images demonstrated
differential optical features of the biopsies in terms of presence of
foaminess in phyllodes in contrast to compactness of fibroadenoma.
Thus, the current study identified differential structural and
molecular signatures in these tumors, to address the diagnostic
ambiguities."