Differential role of glucocorticoid receptor based on its cell type specific expression on tumor cells and infiltrating lymphocytes.

BACKGROUND: The glucocorticoid receptor (GR) is frequently expressed in breast cancer (BC), and its prognostic implications are contingent on estrogen receptor (ER) status. To address conflicting reports and explore therapeutic potential, a GR signature (GRsig) independent of ER status was developed. We also investigated cell type-specific GR protein expression in BC tumor epithelial cells and infiltrating lymphocytes. METHODS: GRsig was derived from Dexamethasone treated cell lines through a bioinformatic pipeline. Immunohistochemistry assessed GR protein expression. Associations between GRsig and tumor phenotypes (proliferation, cytolytic activity (CYT), immune cell distribution, and epithelial-to-mesenchymal transition (EMT) were explored in public datasets. Single-cell RNA sequencing data evaluated context-dependent GR roles, and a cell type-specific prognostic role was assessed in an independent BC cohort. RESULTS: High GRsig levels were associated with a favorable prognosis across BC subtypes. Tumor-specific high GRsig correlated with lower proliferation, increased CYT, and anti-tumorigenic immune cells. Single-cell data analysis revealed higher GRsig expression in immune cells, negatively correlating with EMT while a positive correlation was observed with EMT primarily in tumor and stromal cells. Univariate and multivariate analyses demonstrated the robust and independent predictive capability of GRsig for favorable prognosis. GR protein expression on immune cells in triple-negative tumors indicated a favorable prognosis. CONCLUSION: This study underscores the cell type-specific role of GR, where its expression on tumor cells is associated with aggressive features like EMT, while in infiltrating lymphocytes, it predicts a better prognosis, particularly within TNBC tumors. The GRsig emerges as a promising independent prognostic indicator across diverse BC subtypes.

Structural, magnetic, electric and electrochemical studies on zinc doped magnesium ferrite nano particles - Sol-gel method.

The sol-gel process was used to prepare zinc doped magnesium ferrite (Mg1-xZnxFe2O4) nanopowders obtained from the nitrates of magnesium, zinc and ferrous is precursor materials, maintain the pH value which were then studied for sensing purposes. The crystallite size and phase of the ferrite samples studied by X-ray diffraction (XRD) revealed a pure spinel phase (Mg1-xZnxFe2O4) with a cubic spinel structure and higher crystallite size and etc. The functional groups with possible stretching analysis were taken from Fourier transform infrared spectroscopy (FTIR). The surface features and morphology and the purity of the samples were analysed through a Scanning electron microscope (SEM) and energy dispersive X-ray (EDAX) spectrum respectively. Through the vibrating sample magnetometer (VSM), the magnetic behaviour was studied from relevant parameters such as saturation magnetization (Ms), coercivity (Hc) and retentivity (Mr). The larger Ms in 0.8 has ferromagnetic nature were observed. The dielectric constants (ε'& ε''), dielectric loss (tan Î´) with AC conductivity (σAC) determined through the LCR metre, and electrochemical behaviour of the samples were found through cyclic voltametery. The possible polarizations at lower and higher frequencies are studied The obtained data are extensively examined and understood.

Structural, electronic, intermolecular interaction, reactivity, vibrational spectroscopy, charge transfer, Hirshfeld surface analysis, pharmacological and hydropathy plot on 5-Bromo nicotinic acid - Antiviral study (Hepatitis A, B, and C).

The therapeutic properties of 5-Bromonicotinatic acid (5BNA) were studied for antiviral illnesses like Hepatitis A, Hepatitis B and Hepatitis C and the influence of electron-donating and electron-withdrawing properties of functional groups on the nicotinic acid was evaluated and represented in this study using the DFT approach. The molecular parameters were determined for both gases as well as for various solvent phases. The reactive areas in the compound are examined utilising Fukui analysis. The molecular interactions are accomplished by recognising the different types of bonding found in the compound using the AIM, ELF, LOL, RDG and IRI. Solvation investigations were demonstrated to have an influence on molecular orbital energy, ESP, UV-Vis and NLO analyses. Electron-hole, NBO and Hirshfeld investigations are used to investigate the transfer of charges and interactions inside the molecule. The method of vibrational spectroscopy (IR and Raman) is used to differentiate and identify the various types of vibrations displayed by the compound. The hydropathy plots for the proteins 2A4O, 6CWD and 2OC8 associated with Hepatitis A, Hepatitis B and Hepatitis C illustrate the disquiet and attraction of the amino acids towards the water.

Absorption wavelength (TD-DFT) and adsorption of metal chalcogen clusters with methyl nicotinate: Structural, electronic, IRI, SERS, pharmacological and antiviral studies (HIV and omicron).

The DFT B3LYP-LAND2DZ technique is used to examine interactions of Methyl nicotinate with copper selenide and zinc selenide clusters. The existence of reactive sites is determined using ESP maps and Fukui data. The energy variations between HOMO and LUMO are utilised to calculate various energy parameters. The Atoms in Molecules and ELF (Electron Localisation Function) maps are employed to investigate the topology of the molecule. The Interaction Region Indicator is used to determine the existence of non-covalent zones in the molecule. The UV-Vis spectrum using the TD-DFT method and DOS graphs are used to obtain the theoretical determination of electronic transition and properties. Structural analysis of the compound is obtained using theoretical IR spectra. To explore the adsorption of copper selenide and zinc selenide clusters on the Methyl nicotinate, the adsorption energy and theoretical SERS spectra are employed. Furthermore, pharmacological investigations are carried out to confirm the drug's non-toxicity. The compound's antiviral efficacy against HIV and Omicron is demonstrated via protein-ligand docking.

Comparison of Real-time RT-PCR cycle threshold (Ct) values with clinical features and severity of COVID-19 disease among hospitalized patients in the first and second waves of COVID-19 pandemic in Chennai, India.

Introduction: Real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) of nasopharyngeal/ oropharyngeal swab has been the gold standard test for detection of SARS-CoV-2 infection The relationship between cycle threshold (Ct) values of rRT-PCR and severity of disease remain disputable and not clearly defined in COVID-19. Methodology: This is a single-centered retrospective observational study conducted at Government Corona Hospital (GCH), Guindy, Chennai. In the present study, we compared the Ct value of rRT-PCR from nasopharyngeal swab specimens with a diverse range of symptoms and disease severity among 240 individuals who were hospitalized with COVID-19, viz., mild cases (MC; n = 160), moderately severe cases (MSC; n = 46) and severe cases (SC; n = 34) in the first and second waves of COVID-19 pandemic. Results: The study included 240 hospitalized COVID-19 patients with a median age of 52 years (range 21 to 90 years). MC, MSC, and SC all had median Ct values of 25.0 (interquartile range - IQR 20.0 to 30.5), 29.5 (IQR 23.0 to 34.0), and 29.0 (IQR 24 to 37.5) for the ORF1ab gene. The Ct value differed significantly between mild vs moderate, and mild vs severe cases. The Ct value of SC group with co-morbidity of type 2 diabetes have a significant difference compared to non-diabetes group (p value <0.05). There was a significant difference in the median Ct value of ORF1ab gene among the MSC group and MC but not in the SC group in the first and second waves of the pandemic (p<0.05). Conclusion: We conclude that SARS-CoV-2 Ct values of rRT-PCR alone does not have a role in aiding severity stratification among patients with COVID-19 since the viral dynamics and Ct value may vary due to the emerging variants that occur in different waves of the pandemic.

Impact of COVID-19 on Renal Function: A Multivariate Analysis of Biochemical and Immunological Markers in Patients.

Introduction There have been tremendous continuous efforts to understand the broad spectrum of disease and its sequelae since the start of the coronavirus disease 2019 (COVID-19) pandemic. Several studies have identified biomarkers that correlate with multiple organ failure in COVID-19 patients. The purpose of our study was to evaluate COVID-19-associated kidney injury. Methods This retrospective cross-sectional study was conducted at the Institute of Biochemistry, Madras Medical College, by reviewing the electronic records of 1,000 reverse transcription-polymerase chain reaction (RT-PCR)-confirmed COVID-19-positive patients admitted at the COVID-19 care center. Data were extracted from the case records of 1,000 RT-PCR-positive patients with different CT chest grades plus comorbid conditions such as type 2 diabetes mellitus (T2DM), systemic hypertension (SHT), coronary artery disease (CAD), chronic obstructive pulmonary disease (COPD), and cerebrovascular accident (CVA) as Group I (n = 500). Group II (n = 500) comprised of COVID-19-positive patients with no comorbid conditions. The data were recorded from all the patients at the time of admission, prior to starting treatment. Patients with comorbid and non-comorbid conditions were compared according to different CT grades. Results COVID-19 patients with different CT grades showed a significant relationship with creatinine, sodium, potassium, C-reactive protein (CRP), ferritin, total protein, and albumin with p-values of 0.04, 0.01, 0.02, 0.000, 0.00, 0.00, and 0.000, respectively, in Group I. In Group II, with various grades of CT changes, the neutrophil-lymphocyte ratio (NLR) and creatinine showed no significance. The sodium, potassium, CRP, ferritin, total protein, and albumin showed low significance with the chest CT grades. Conclusions Our study demonstrated that COVID-19 can cause mild to moderate renal impairment in COVID-19 patients. Multiple factors contributed to this, such as the higher angiotensin-converting enzyme 2 (ACE2) expression on kidney cells, microinflammation, increased blood clotting, and probable direct infection of the kidney. A high NLR, increased inflammatory markers, and altered renal function analytes such as urea, creatinine, sodium, potassium, total protein, and albumin also confirmed this.

Biochemical predictors for Sars-Cov-2 severity.

It is of interest to assess the inflammatory marker profile in SARS-CoV-2 patients and to correlate the levels of systemic inflammatory biomarkers such as neutrophil-to-lymphocyte ratio (NLR), C-Reactive Protein CRP, Ferritin, Creatine kinase (CK), Lactate dehydrogenase (LDH) and liver function analytes total serum proteins, albumin, total bilirubin, direct bilirubin, alkaline phosphatase, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) with the severity of SARS-CoV-2 infections. A total of 1000 COVID-19 positive patient's data were collected. Laboratory assessments consisted of NLR (neutrophil-lymphocyte ratio) by cell counter, C Reactive Protein (CRP) by immunoturbidimetry, Ferritin by electrochemiluminescence (ECLIA) and Creatine Kinase (CK), Lactate Dehydrogenase (LDH), Alkaline phosphatase (ALP), Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Total Bilirubin, Direct Bilirubin, Total Protein and Albumin by spectrophotometry. The mean plasma CRP levels, NLR, ferritin, CK and LDH levels were higher in severe cases than in non-severe cases, and the difference was statistically significant (p<0.05). All liver function tests such as the total and direct bilirubin, AST, ALT, ALP, total protein and albumin were higher in severe patients than non-severe patients and the difference was statistically significant (p<0.05). Data indicate that NLR, CRP, Ferritin, CK, LDH and liver function analytes have a crucial role as prognostic markers for SARS-CoV-2 infections and hence should be routinely recommended for risk assessment and stratification of the patients to reduce the associated morbidity and mortality.

In vitro biological properties of Streptomyces cangkringensis isolated from the floral rhizosphere regions.

This context was investigated to determine in vitro antimicrobial, antioxidative, and anticancer traits of crude ethyl acetate extract of Streptomyces cangkringensis strain TSAS 04 isolated from soil sample of rhizosphere regions. The antimicrobial activity of ethyl acetate extract of strain TSAS 04 was determined against indicator pathogens using disc diffusion assay which exhibited maximum zones of inhibition of 20.6 ± 0.3 and 16.3 ± 0.6 mm against Bacillus subtilis and Trichoderma viride, respectively. In vitro antioxidant properties of the crude ethyl acetate extract were performed using standard methodologies. The extract revealed maximum DPPH and ABTS•+ radical scavenging activities of 51.1 ± 0.39 and 81.25 ± 0.33%, respectively. Likewise, maximum phosphomolybdenum reduction and Fe3+ reduction of the crude ethyl acetate extract of strain TSAS 04 were estimated 76.18 ± 0.10 and 89.01 ± 0.44%, respectively. In vitro anticancer trait of the extract was determined against HeLa cell line using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay which showed anticancer activities in a dose dependent manner with an IC50 value of 410.5 µg/mL. Fourier transform infrared spectroscopy (FT-IR) and Gas chromatography-mass spectrometry (GC-MS) analyses indicated the presence of distinct functional groups and bioactive components in the extract, respectively. In conclusion, S. cangkringensis strain TSAS 04 showed its effectiveness as ideal bioactive agent by exhibiting substantial antimicrobial, antioxidant, and anticancer properties.

Impact of Radiotherapy on Neck Dissection Nodal Count in Patients With Head and Neck Cancer.

OBJECTIVES/HYPOTHESIS: Our study aimed to review the impact of preoperative radiotherapy (RT) and other factors on the lymph node count of neck dissection (ND) specimens from patients with head and neck cancer (HNC). A retrospective study was conducted on all patients with head and neck cancers who had undergone NDs in Singapore General Hospital between 1992 and 2013. STUDY DESIGN: Retrospective study. METHODS: Patients were categorized into two groups: patients treated with RT with or without chemotherapy before ND and patients who had undergone ND surgery without previous history of RT. The primary endpoint for this study would be the lymph node count from ND. RESULTS: The study cohort consists of 1,024 NDs on 829 patients. There were 597 (58.3%) radical/modified radical NDs involving levels I-V. Within this group, 75 (12.6%) NDs had preoperative RT. Preoperative RT and age were found to significantly reduce nodal yield in both univariate and multivariate analysis in the radical/modified radical ND subgroup. In our multivariate analysis, preoperative RT was shown to decrease the nodal yield by 7.464 (P = .0002, 95% confidence interval [CI]: -11.35 to -3.58). Advanced age independently decreases nodal yield, even after accounting for the effect of RT (P = .0002, 95% CI: -0.27 to -0.08). In addition, preoperative RT has a more pronounced effect in reducing lymph node count in the older age group. CONCLUSIONS: Preoperative RT and advanced age are independent and synergistic factors that reduce nodal count from NDs in patients with head and neck cancers. LEVEL OF EVIDENCE: 4 Laryngoscope, 130: 1947-1953, 2020.

Adherence of head and neck squamous cell carcinoma patients to tumor board recommendations.

BACKGROUND: Multidisciplinary team (MDT) meetings or tumor boards (TBs) are fundamental components of cancer treatment. Although their primary function is improved outcomes, this aspect is often underreported. The main objective of this study was to analyze the outcomes of patients with head and neck squamous cell carcinoma (HNSCC) discussed at TBs, and to compare the effect of adherence and nonadherence to recommended treatment plans on outcomes. METHODS: Retrospective data analysis was conducted of HNSCC patients those who were adherent and nonadherent to TB therapy recommendations during 2008-2009 at a comprehensive cancer center. Fisher's exact test and t test were used for group-wise comparison, and Kaplan-Meier and logistic regression models, for survival analysis and determination of the contributing factors to nonadherence. RESULTS: Comprehensive Treatment plans were recommended by TBs in 293 HNSCC patients with curative intent. Seventy-two patients were excluded based on the selection criteria. Among the remaining 221 patients, 172 (77.9%) were adherent to TB recommendations, while 49 (22.1%) failed to comply. Patient (n = 36; 73.5%), clinician (n = 2; 4.1%), and disease-related (n = 11; 22.4%) factors were significant contributors to nonadherence. Mean (±standard deviation (SD)) survival time was 55.6 ± 2.32 and 29.1 ± 4 months in the adherent and nonadherent groups, (P < .0001, respectively). Multivariate analyses showed that gender, ethnicity, higher T-stage, and multimodal treatment were associated with nonadherence. CONCLUSION: Adherence to TB recommendations improved overall survival, reflecting the importance of interdisciplinary expertise in contemporary cancer treatment. Early identification and intervention is crucial in "at risk" patients to prevent subsequent drop-out from optimal cancer care.

Modeling through space magnetic shielding over the tetrafluoroborate (BF4-) and tetrachloroborate (BCl4-) anions.

The GIAO-B3LYP method was employed to calculate the isotropic NMR shielding increments of a diatomic hydrogen probe above the tetrafluoroborate (BF4-) and tetrachloroborate (BCl4-) anions in tetrahedral (Td) symmetrical structure. The covalently bonded hydrogen nuclei are held in various positions over the anion to obtain the isotropic shielding increment. The NMR chemical shift shielding increments experienced by the proximal proton of diatomic hydrogen have been mapped as a function of their position X, Y, and Z in Cartesian coordinates relative to the center of the anion. A mathematical function was fit to this 3D shielding increment surface at each of the four distances from the plane of the anion, and also, a single mathematical equation was used for predicting the shielding caused by the anion. This equation could be integrated into a molecular mechanics-chemical shift prediction program which could help in the structural determination of structures having these features. In addition, the effect of shielding/deshielding of various probes such as H-atom, H2 molecule, He atom, proximal hydrogen of CH4 molecule, and ghost atom was also studied through their calculated shielding increments (∆σ) with respect to their distance above the center of the both anions. Also, natural bond orbital (NBO) and highest occupied molecular orbital-lowest unoccupied molecular orbital analysis calculations were carried out for both the anions along with the H2 probe placed above the center of the anions in order to investigate the most stable interactions, atomic charges, chemical reactivity, and kinetic stability. Graphical abstract.

Facile hydrothermal bio-synthesis of cellulose acetate templated CuS nanorods like fibres: antibacterial, cytotoxicity effects and DNA cleavage properties against A549 lung cancer cells.

In this research, the hydrothermal method was used for synthesising cellulose acetate (CA) templated nanorods like CuS fibres using vegetable extract (Brassica oleracea var. italica). These extracts act as a reducing agent in the presence of CA. Surprisingly, when the same reaction was carried out in the absence of CA and broccoli extract, structural morphology disappeared and was found as agglomerated. In the presence of cellulose templated extract mediated CuS has revealed as nanorods like fibres and was confirmed by field emission scanning electron microscope analysis. Their crystallinity property of CuS nanoparticles (NPs) and cellulose templated biosynthesised CuS NPs was analysed and compared using X-ray diffraction technique. The biological activities of the obtained product were examined for antibacterial assessment against two bacterial strains that include two-gram negative strains (E.Coli and S. aureus). The nanostructured product found to exhibit excellent antibacterial agent against all the strains. Biosynthesised nanostructure showed its efficacy against A549 lung cancer cells which might attribute to a larger surface to volume ratio of nanorods like fibres. The authors observation suggest that CuS nanorods like fibres can significantly reduce the cell growth with IC50 value of 31.2 µg/ml.

Fish Scales as Potential Substrate for Production of Alkaline Protease and Amino Acid Rich Aqua Hydrolyzate by Bacillus altitudinis GVC11.

Fish processing industries generate large quantities of fish scales as processing waste, if not treated leading to environmental pollution. Fish scales are hard to degrade, hence cause difficulty in waste management. In this context present study was made to utilize fish scales as substrate for the production of alkaline protease by Bacillus altitudinis GVC11 and subsequently amino acid rich aqua hydrolyzate. B. altitudinis GVC11 efficiently utilized five types of fish scales as substrates and produced maximum alkaline protease using Labeo rohita (28,150 U/mL) followed by Catla catla (23,320 U/mL) at 48 h and Cyprinus carpio (17,146 U/mL) Mugil cephalus (18,917 U/mL), Cirrhinus mrigala (12,430 U/mL) at 72 h. The HPLC analysis of protein hydrolyzate obtained after fermentation was enriched in essential amino acids, leucine, isoleucine, phenylalanine, lysine and non-essential amino acids, tyrosine, arginine and cysteine which can be used as animal feed supplement and organic fertilizer.

Occurrence of spintronics behaviour (half-metallicity, spin gapless semiconductor and bipolar magnetic semiconductor) depending on the location of oxygen vacancies in BiFe0.83Ni0.17O3.

The current communication signifies the effect of oxygen vacancies (OVs) both qualitatively and quantitatively in multiferroic BiFe0.83Ni0.17O3 by an in-depth atomic-level investigation of its electronic structure and magnetization properties, and these materials have a variety of applications in spintronics, optoelectronics, sensors and solar energy devices. Depending on the precise location of OVs, all the three types of spintronic material namely half-metallic, spin gapless semiconductor and bipolar magnetic conductor have been established in a single material for the first time and both super-exchange and double-exchange interactions are possible in accordance with the precise location of OVs. We have also calculated the vacancy formation energies to predict their thermodynamic stabilities. These results can highlight the impact and importance of OVs that can alter the multiferroic properties of materials.

Radix Entomolaris - a rare case series.

INTRODUCTION: The success of root canal treatment is determined by satisfying the basic principles of complete removal of the endodontic pathology through chemo-mechanical cleansing of the root canals followed by shaping and then by obturation to provide the ideal hermetic seal. To achieve such success a thorough knowledge of the root canal anatomy is a basic requirement. Several anatomic variations of the mandibular molars have been reported among which is the reportedly rare Radix Entomolaris(RE), a mandibular molar with an additional root located lingually. AIMS AND OBJECTIVES: To present five cases of RE diagnosed pre-operatively using radiographs and subsequently successfully endodontically treated. We also aim to highlight the considerations for the diagnosis and management of RE in general dental practice. CONCLUSION: Even though RE is rarely encountered in general dental practice, the possibility that it may occur warrants the need to have sufficient knowledge regarding diagnosis and the appropriate modifications in endodontic management of these teeth. Preparedness coupled with a carefully modified clinical approach aids in successful management of RE and ensures that these cases could be handled with ease.

yciM is an essential gene required for regulation of lipopolysaccharide synthesis in Escherichia coli.

The outer membrane of Gram-negative bacteria is an asymmetric lipid bilayer consisting of an essential glycolipid lipopolysaccharide (LPS) in its outer leaflet and phospholipids in the inner leaflet. Here, we show that yciM, a gene encoding a tetratricopeptide repeat protein of unknown function, modulates LPS levels by negatively regulating the biosynthesis of lipid A, an essential constituent of LPS. Inactivation of yciM resulted in high LPS levels and cell death in Escherichia coli; recessive mutations in lpxA, lpxC or lpxD that lower the synthesis of lipid A, or a gain of function mutation in fabZ that increases the formation of membrane phospholipids, alleviated the yciM mutant phenotypes. A modest increase in YciM led to significant reduction of LPS and increased sensitivity to hydrophobic antibiotics. YciM was shown to regulate LPS by altering LpxC, an enzyme that catalyses the first committed step of lipid A biosynthesis. Regulation of LpxC by YciM was contingent on the presence of FtsH, an essential membrane-anchored protease known to degrade LpxC, suggesting that FtsH and YciM act in concert to regulate synthesis of lipid A. In summary, this study demonstrates an essential role for YciM in regulation of LPS biosynthesis in E. coli.

(2E,4E)-Ethyl 5-(2,4-di-chloro-phenyl-sulfon-yl)penta-2,4-dienoate.

In the title compound, C13H12Cl2O4S, both C=C double bonds adopt an E conformation. The S atom has a distorted tetra-hedral geometry with bond angles ranging from 103.03 (12) to 118.12 (13)°. The eth-oxy-carbonyl group is disordered over two sets of sites, with site-occupancy factors of 0.739 (11) and 0.261 (11). In the crystal, C-H⋯O inter-actions link the mol-ecules into chains mol-ecules running parallel to the a axis.

Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer.

Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage.

Collagen-coated polycaprolactone microparticles as a controlled drug delivery system.

OBJECTIVE: Polycaprolactone (PCL) microparticles coated with acetylated collagen have been assessed for use as a controlled drug delivery system. METHOD: The surface morphology, drug encapsulation and release profile of PCL microparticles and collagen-coated PCL microparticles containing doxycycline hydrochloride (DH) have been investigated in order to develop a controlled release system which would in addition act as a scaffold for cell attachment. PCL microparticles were prepared by emulsion solvent evaporation technique and loaded with DH. Since the encapsulation was found to be low, PCL microparticles were coated with acetylated collagen containing DH, to increase the drug availability. Collagen was modified by acetylation to shift its isoelectric point and to have acetylated collagen solution at pH 7.0. The microparticles were characterized using a scanning electron microscope (SEM) and the in vitro drug release profile was determined using HPLC. RESULTS: Uniform sized (approximately 1000 nm) PCL microparticles were prepared using 4% PVA in the external water phase. Acetylated collagen at pH 7.0 was coated onto the PCL microparticles. This resulted in microparticles of uniform size at neutral pH. PCL acts as a support for collagen which acts as a scaffold for cell attachment. In vitro drug release studies show that collagen-coated PCL microparticle is a promising candidate for controlled drug delivery system having release duration of over 10 days. In vitro fibroblast culture studies reveal that collagen is a good substrate for cell attachment and would provide a stable environment for cell proliferation and regeneration. Thus, this system would be ideal for a short-term drug delivery to create an aseptic environment where cells can adhere and proliferate to regenerate the site.