The Development of a Novel Controlled Release Drug Delivery System

The aim of this research was to formulate, characterise and assess the feasibility of a novel drug delivery system known as the in situ gelling matrix (ISGM) where a hydrophilic polymer is suspended in a non-aqueous solvent that converts into a gel when injected subcutaneously or intramuscularly thus giving a controlled release matrix for a drug. Although the concept has been patented with claims that this kind of drug delivery is achievable in theory for a wide variety of candidate substances, actual formulation studies for making a commercially viable product for this technology are completely lacking in practice. The research embodied in this thesis addresses this lack. Initial studies involved conducting a biocompatibility study using the HET-CAM (hens egg test - chorioallantoic membrane) test on a range of possible ingredients for the delivery system. The materials deemed biocompatible were then carried through to a screening process where the physical stability of the hydrophilic polymers in non-aqueous solvents was monitored. It was found that the hydrophilic polymers tested sedimented rapidly in the non-aqueous solvents indicating such a system was not physically stable. Consequently, density-inducing or viscosity-inducing agents were added to the non-aqueous solvents to retard the sedimentation rate. The addition of polycarbophil, a viscosity-inducing agent, clearly increased the viscosity of the system. However, undesirable formation of polycarbophil globules occurred during the manufacturing process, which caused batch-to-batch variations in the viscosity of the continuous phase. Various manufacturing methods were tested before arriving at the optimum procedure to prevent globule formation using a high speed dispersion tool. A final physical sedimentation analysis of candidate continuous phases and hydrophilic polymers was conducted for determining the ideal combination of ingredients to use in the system. These investigations finally led to the adoption of an optimum mix of components consisting of 10% (w/w) hydroxypropyl methylcellulose (HPMC) (the hydrophilic polymer) suspended in a continuous phase of propylene glycol (the non-aqueous solvent) containing 0.67% (w/w) polycarbophil (the viscosity inducing agent). Using this mix of components, the in situ gelling matrix system was then subjected to various characterisation studies including infrared (IR), differential scanning calorimetry (DSC), ultraviolet-visible (UV-Vis) spectrophotometry and redispersion studies. The chemical stability of the hydrophilic polymer and the continuous phase (the non-aqueous solvent and polycarbophil) was monitored and were found to be chemically stable over a 9 month period. The feasibility of the in situ gelling matrix technology as a controlled release device was assessed using the drug propranolol. In vitro drug release studies were conducted using a custom-built dissolution apparatus. The effect of various parameters such as the concentration of the hydrophilic gelling agent on the drug release rate was investigated. Increasing the concentration of the gelling agent in the formulation resulted in a slower rate of release. The drug release data were modelled using the Higuchi relationship and a power law relationship to compare the effects of the various parameters on the release rate Stability studies on the drug in the in situ gelling matrix system were carried out by storing samples in accelerated ageing conditions of 40 C / 75% relative humidity for 4 weeks. During this time, the samples were analysed each week by high performance liquid chromatography (HPLC). These demonstrated that no apparent drug degradation had occurred over the 4-week period. This indicates that the drug propranolol in the in situ gelling matrix system is stable under ambient conditions for at least 4 weeks. The results of this study demonstrated that the in situ gelling matrix technology is potentially viable as a drug delivery system and provide a practical methodology for the commercial development of such systems

Biofloc Technology for Sustainable Growth of Shrimp Species: Litopenaeus Vannamei

Aquaculture stands as the fastest-growing food-producing sector globally, undergoing continuous development, expansion, and intensification across all regions. Despite the anticipation of higher production levels, the global growth of aquaculture is constrained by the severe scarcity of water and the limited availability of suitable land. Biofloc systems have emerged as a viable solution tailored for water-scarce areas. This innovative system offers a potential food source for shrimp reared in an environmentally friendly, limited or zero water exchange environment, with minimal effluents released into the surrounding ecosystem. The present study was conducted at a corporate aquaculture farm facility located in Cuddalore district, Tamilnadu. The research focused on evaluating the water quality, survival rates, and growth performance of Litopenaeus vannamei, ranging from post-larvae (PL-9) to 26.6 grams, over a 120-day period within a Biofloc system. Three cement tanks, designated as C1 (control) and C2, C3 (test), were utilized, each with a stocking density of 120 PL/sq.m. After reaching a weight of 2 grams, the shrimp were transferred to grow-out ponds. The results indicated that shrimp reared in Biofloc tanks exhibited significantly higher final weights, survival rates, and favorable water quality parameters compared to the control group, which relied solely on commercial feed. Significantly, as the biofloc volume rose, there was a noteworthy decrease in the requirement for feed application, thereby establishing the Biofloc system as a financially efficient option for shrimp cultivation

3D Evaluation of Maxillary Sinus Using Computed Tomography: A Sexual Dimorphic Study

Purpose. Gender determination is considered to be an important step in the reconstruction of the biological profile in forensic medicine. Maxillary sinus can be used for identification of sex when other methods are indecisive. Computed tomography (CT) provides an excellent method for examining maxillary sinuses. Hence the aim of the study was to determine the accuracy of gender determination using maxillary sinus with CT. Materials and Methods. CT images were used to measure the mediolateral, superoinferior, and anteroposterior dimensions and the volume of the maxillary sinuses in 100 patients (50 males and 50 females) to determine the gender of an individual for forensic identification. Discriminative analysis was done using the values derived and the t-test for independent samples was used to compare these values in males and females. Results. The accuracy rate was found to be 84% in males and 92% in females with the mean accuracy of 88%. Conclusion. Our study concludes that gender determination can be done using measurements of maxillary sinus through CT when other methods are unavailable. The prediction rate can be increased by including volume of the maxillary sinus

4-Bromo-3-{N-[2-(3,4-dimethoxy­phen­yl)eth­yl]-N-methyl­sulfamo­yl}-5-methyl­benzoic acid monohydrate

In the title compound, C19H22BrNO6S·H2O, the dihedral angle between the planes of the two benzene rings is 3.1 (1)°. These rings are stacked over one another with their centroids separated by 3.769 (2) Å, indicating weak π–π inter­actions. In the crystal structure, mol­ecules are linked by O—H⋯O and O—H⋯(O,O) hydrogen bonds involving the water mol­ecule, forming a two-dimensional network parallel to (001)

Adaptive Extended Kalman Filter for Orbit Estimation of GEO Satellites

The aim of this paper is to develop Adaptive Extended Kalman Filter (AEKF) algorithm for the precise orbit estimation of GEO satellites (viz., GSAT-10 – Geostationary satellite and IRNSS-1A – Geosynchronous satellite) using two-way CDMA range measurements data from different ranging stations located in India. It brings forward the effectiveness of AEKF algorithm over Extended Kalman Filter (EKF) algorithm. EKF algorithm is adapted by updating process noise covariance (Q), measure of uncertainty in state dynamics during the time interval between measurement updates and measurement noise covariance (R), function of measurement update based on measurement residual. This paper addresses the modeling of all errors in measurement domain and the computation of measurement residual using observed and modeled measurement ranges for all stations. The filter incorporates non-linear model for measurement update, non-linear dynamic model for time update and estimation is carried out at every second. This paper also elaborates the development of indigenous full force propagation model considering all the perturbations during orbit prediction period for GEO Satellites. Adaptation of EKF algorithm in precise orbit estimation is done primarily for making the algorithm more robust by countering the uncertainties in process and measurement noises, resolving the problem of manual tuning of the filter and also by keeping the error covariance (P) consistent with real performance. Adaptation of Q is implemented based on the error in system states with respect to estimated states while Adaptation of R is implemented based on the error in observed measurements with respect to measurements obtained from estimated state vectors (aposteriori measurement expectation). Analysis of the estimated results using the above proposed method is carried out by comparison of Station-wise range residues for both the methods (AEKF and EKF). Consistency of obtained orbit for GEO Satellites are validated using overlapping technique for both AEKF and EKF methods, orbit estimated from these methods are also validated by comparing with batch least squares method and filter behavior is continuously monitored during data gaps by observing error covariance(P) for both the methods. Keywords: Kalman Filtering, Process Noise Covariance, Measurement Noise Covariance, Orbit Estimation, CDM

A SHORT REVIEW ON POLYCYSTIC OVARY SYNDROME

Polycystic ovary syndrome (PCOS) is said to be the commonest endocrine disorder in women of reproductive age with a heterogeneous presentation, which includes hyperandrogenism and ovulatory dysfunction. Polycystic ovary syndrome usually has a peri-pubertal onset;the present review discuss about the causes,complications,risck factors,dianosis and treatment.Key words:Polycystic ovary syndrome (PCOS),Hyperandrogenism,Treatmen

MITIGATION OF VOLTAGE DISTURBANCES BY CONVERTER BASED DVR

An increasing demand for high quality, reliable electrical power and increasing number of distorting loads may leads to an increased awareness of power quality both by customers and utilities. The most common power quality problems today are voltage sags, harmonic distortion and low power factor. Voltage sags is a short time (10 ms to 1 minute) event during which a reduction in r.m.s voltage magnitude occurs. It is often set only by two parameters, depth/magnitude and duration. The voltage sags magnitude is ranged from 10% to 90% of nominal voltage and with duration from half a cycle to 1 min. Voltage sag remains a serious power-quality (PQ) problem by being the most common and causing more economic losses. The dynamic voltage restorer (DVR) is a definitive solution to address the voltage-related PQ problems. Conventional topologies operate with a dc link, which makes them bulkier and costlier; it also imposes limits on the compensation capability of the DVR. Topologies with the same functionality, operating without the dc link by utilizing a direct ac–ac converter, are preferable over the conventional ones. Since no storage device is employed, these topologies require improved information on instantaneous voltages at the point of common coupling and need flexible control schemes depending on these voltages. Therefore, a control scheme for DVR topologies with an ac–ac converter, based on the characterization of voltage sags is proposed in this paper to mitigate voltage sags with phase jump. The main objective of this project is, the control scheme is tested on an inter phase ac–ac converter topology to validate its efficacy based on characterization of voltage sags and to mitigate the voltage sags. Detailed simulations to support the same have been carried out in MATLAB, and the results show the effectiveness of proposed method

Maternal and perinatal outcome in eclampsia complicated by posterior reversible encephalopathy syndrome; a three years’ experience in a tertiary care hospital

Background: PRES can be associated with number of medical conditions and was observed frequently in patients with preeclampsia and eclampsia. Neuroimaging is important for the diagnosis of PRES. Study was conducted to find out the maternal and perinatal outcome in patients with eclampsia complicated by posterior reversible encephalopathy syndrome (PRES).Methods: This is a retrospective study done at St. Johns Medical College Bangalore, between October 2013 and October 2016. We reviewed case records of all the patients with eclampsia who underwent neuro imaging studies and a diagnosis of PRES was made. The maternal and perinatal outcomes in these women were studiedResults: In the past three years we had 55 cases of eclampsia who underwent neuroimaging studies for persistent neurological symptoms after 24 hours of MgSO­4 treatment. Of these women 30 were diagnosed to have PRES. In the present study PRES was common in multiparous women and more in patients with antepartum eclamptic women. Mean age at diagnosis of PRES was 26±5.1 years. Common presenting symptoms were headache (93.3%) and vomiting (53.3%). The mean SBP/DBP was 180/110 mmHg. All patients who had recurrent seizures were controlled with MgSO­4 alone. 53.3% of our patients had eclampsia related complications and 36.7% required ICU care. There were 3 maternal deaths (10%). Perinatal mortality was 20%.Conclusions: Neuroimaging in eclamptic patients with persistent neurological symptoms could help in early diagnosis of PRES and multidisciplinary approach in management could contribute significantly in reducing the maternal mortality and morbidity

1-Naphthyl 9H-carbazole-4-sulfonate

In the title compound, C22H15NO3S, the plane of the carbazole ring system forms a dihedral angle of 65.06 (4)° with the naphthalene ring system. In the crystal structure, a weak intra­molecular C—H⋯O inter­action is observed between the naphthalene ring system and the sulfonate group. Two weak inter­molecular C—H⋯O inter­actions are also observed

Panorama of neoplasms of upper GI tract: a 5 year research study

Background: The diseases of the gastrointestinal tract (GIT) are the most common and leading cause of morbidity and mortality than the disorders of any other systems of the body. Gastrointestinal (GI) tract tumors are one of the most common cancers accounting for 11% of all cancers. Among these tumors, upper gastrointestinal tract malignancies are quite aggressive with a dismal prognosis. Malignant tumors are most common than benign. The most common carcinoma of the esophagus is Squamous cell carcinoma (SCC). Incidence of SCC is less than 5 per 100,000 populations in males and 1 per 100,000 populations in females. Gastric cancer was the second most common cancer in the World and 60% of them occurred in developing countries. The most common carcinoma of the Stomach is Adenocarcinoma.Aim & Objectives: To study the spectrum of neoplastic lesions of the upper gastrointestinal tract by the examination of endoscopic biopsies and surgically resected specimens. To determine the degree of severity of the malignancies by assessing the depth of invasion, Lymph nodal & Omental spread.Methods: The present study is both retrospective & prospective study for a period of 5 years from January 2007 to December 2011. The sample size includes all the endoscopic biopsies & surgically resected specimens of gastrointestinal tract received at Department of Pathology, S.V. Medical College, Tirupati. The study also obtained clearance from the ethical committee of the institution. The biopsy specimens thus obtained were fixed in 10% buffered neutral formalin. The sections were stained routinely with H & E. Special stains and IHC done wherever necessary.Results: we have received 120 specimens regarding the upper gastrointestinal system. Among these 120 specimens, 71 specimens were endoscopic biopsies & 49 specimens were surgically resected specimens. Out of 71 Endoscopic biopsies 28 biopsies were malignant among which 2 was esophagus and 26 were stomach. Out of 49 surgically resected specimens 1 was benign and 32 were malignant tumors. Out of 59 neoplasms of stomach there were single cases each of Sub mucosal Lipoma, Malignant lymphoma, GIST & 56 cases of Adenocarcinoma & its variants were noted.Conclusion: Most of the neoplasms are of stomach (97%). All the neoplasms are malignant except one benign lesion sub mucous lipoma of stomach. Most of the neoplasms of stomach were Adenocarcinoma (96.5%). Both tumors of esophagus were squamous cell carcinoma occurred after 50 years of age.