Photodynamic therapy in cancer treatment: properties and applications in nanoparticles

Most of the treatment strategies for tumors and other disorders is photodynamic therapy (PDT). For several years, increasing the efficiency of nanostructured treatment devices, including light therapy, has been considered in different treatment methods. Light Dynamics The use of nanomaterial in this method's production and progress. The use of nanoparticles as carriers is a promising accomplishment, since all the criteria for an ideal photodynamic therapy agent can be given with these nanomaterials. The kinds of nanoparticles that have recently been used in photodynamic therapy are mentioned in this article. Latest advancements are being explored in the use of inorganic nanoparticles and biodegradable polymer-based nanomaterial as carriers of photosynthetic agents. Photosynthetic nanoparticles, self-propagating nanoparticles, and conversion nanoparticles are among the successful photodynamic therapy nanoparticles addressed in this report.

Effects of dietary replacement of fish meal by soybean meal on growth, feed utilization, and health condition of stinging catfish, Heteropneustes fossilis

Soybean meal (SBM) is a cost-effective alternative protein source to replace costly fish meal in aquaculture. This present study determined to measure the effects of replacing fish meal (FM) protein with SBM on growth, feed utilization, and health condition of stinging catfish, Heteropneustes fossilis. Four isonitrogenous (35 %) diets were applied in four treatment groups designed as SBM₀, SBM₂₅, SBM₅₀, and SBM₇₅, where 0 %, 25 %, 50 %, and 75 % of FM protein were substituted by SBM, respectively. Significantly higher mean final weight (g), weight gain (g), percent weight gain (%), specific growth rate (% day^-1), and protein efficiency ratio (PER) were recorded in SBM₀, SBM₂₅, and SBM₅₀ groups than SBM₇₅ group. Consequently, significantly lower feed conversion ratio (FCR) was found in SBM₀, SBM₂₅, and SBM₅₀ groups than SBM₇₅ group. Moreover, protein content of whole-body carcass was significantly higher in SBM₂₅ and lower in SBM₀ group however, lipid content was significantly higher in SBM₀ and SBM₇₅ than in other groups. Hemoglobin, red blood cells, and white blood cells were significantly higher in SBM₀, SBM₂₅, and SBM₅₀ groups compared to SBM₇₅. However, the higher the substitution of FM protein by SBM in diets higher the values of glucose. Morphological analysis of the intestine including villi length (μm), width (μm), and area (mm²); crypt depth (μm); wall thickness (μm); abundance of goblet cell (GB); and muscle thickness (μm) showed an increasing trend in fish fed diet containing upto 50 % replacement of FM protein by SBM. Therefore, the results suggest that SBM could replace upto 50 % FM protein in diets of H. fossilis without compromising growth, feed efficiency, and health status.

Spatiotemporal variation and toxicity of trace metals in commercially important fish of the tidal Pasur River in Bangladesh

The release of toxic metals in the water creates an adverse condition for the living organisms (e.g., fish). The aim of this research was to learn more about the spatiotemporal variations and toxicity of heavy metals (As, Cr, Cd, and Pb) among fish species that are economically important (Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Mystus vittatus, Glossogobius giuris, Harpadon nehereus, Pseudapocryptes elongatus, Polynemus paradiseus, and Sillaginopsis panijus) collected from Pasur River. Heavy metal (HMs) concentrations were evaluated using the atomic absorption spectrometry (AAS) technique. Most of the metals showed no significant variation spatiotemporally (p ˃ 0.05) except As and Cr showed substantial variation in terms of seasons (p ˂ 0.05). All fish species' Cr and Pb concentrations, as well as As and Cd values, were estimated to be greater than FAO/WHO tolerable concentrations, implying that these metals pose danger to humans. HM has a total hazard quotient (THQ) value in individual fish species reported to be greater than 1, whereas an individual metal, arsenic, exceeds the standard value (THQ > 1), causing a significant noncarcinogenic issue in the study region. The target hazard (TR) value for As and Pb exceeds the USEPA norm (10^-4) suggesting that long-term consumption of fish poses a chronic cancer risk to the people in the study field. According to the findings, the fish in the Pasur River are unfit for human consumption. The correlation matrix (CM) indicates that sources of metals are similar (e.g., industries, ships, agricultural inputs, etc.).

The effect of metal substitution in CsSnI3 perovskites with enhanced optoelectronic and photovoltaic properties

Non-toxic lead-free halide metal perovskites have gained significant interest in photovoltaic and optoelectronic device applications. In this manuscript, we have studied the structural, electronic, mechanical, and optical properties of eco-friendly cubic CsSn_1-x Cu _x I₃, (x = 0, 0.125, 0.25, 0.5, 1) perovskites applying first-principles pseudopotential-based density functional theory (DFT). Cu-doped CsSnI₃ has a large impact on the band gap energy viz. the transition of direct band gap towards the indirect band gap. The mechanical properties demonstrate that the pristine and Cu-doped CsSnI₃ samples are mechanically stable and their ductility is enhanced by Cu doping. The mechanical stability and ductility favors the suitability of pure and Cu-doped samples in the thin film industry. The absorption edge of Cu-doped CsSnI₃ moves towards the lower energy region in comparison with their pure form. In addition, the high dielectric constant, high optical absorption, and high optical conductivity of Cu-doped CsSnI₃ materials suggests that the studied materials have a broad range of applications in optoelectronic devices, especially solar cells. A combined analysis of the structural, electronic, mechanical and optical properties suggests that CsSn_1-x Cu _x I₃, (x = 0, 0.125, 0.25, 0.5, 1) samples are a suitable candidate for photovoltaic as well as optoelectronic device applications.

Comparison of P2Y12 receptor inhibition by clopidogrel and prasugrel in patients undergoing percutaneous coronary intervention

Dual antiplatelet treatment (DAPT) with aspirin and clopidogrel is vital after percutaneous coronary intervention (PCI). Clopidogrel and prasugrel act on P2Y12 platelet surface receptors. Both these P2Y12 inhibitors are pro-drugs and depend on cytochrome system of the liver for their conversion to active metabolite. There is growing concern regarding suboptimal response in platelet inhibition by clopidogrel. Verify Now system got approval by Federal Drug Administration, USA, for assessing platelet function as its result is almost comparable to gold standard Light Transmission Aggregometry (LTA). There are no data on the prevalence of clopidogrel resistance in Bangladeshi population. Prasugrel, as an antiplatelet drug, is a newer introduction in this country. This study will show light on the efficacy of these drugs on our population especially in patients who undergo PCI where DAPT is mandatory. A total 120 (60 diabetics) patients with Acute Coronary Syndrome (ACS), were alternatively given 600 mg clopidogrel loading dose (LD) followed by 75 mg maintenance dose (MD) daily or 60 mg LD of prasugrel followed by 10 mg MD daily. Five samples of blood were taken at different time intervals over a period of 2 weeks. Measurement of percent inhibition of P2Y12 was done by VerifyNow. Patients who showed less than 20% inhibition (clopidogrel resistant) at any stage were switched to prasugrel. The outcomes of clopidogrel, prasugrel and clopidogrel switched to prasugrel groups were then compared. Nearly half (46.7%) of the patients in the clopidogrel group was found resistant to the drug as opposed to none in the prasugrel group. No difference was found between diabetic and non-diabetic subjects with respect to drug resistance. Intracoronary blood samples showed high degree of platelet inhibition with prasugrel. There was a gradual decline of platelet inhibition over two weeks with prasugrel. Almost fifty percent of the population is clopidogrel resistant in our study. Prasugrel is a much more potent antiplatelet drug and should be preferred in patients undergoing PCI. Prasugrel may also show resistance over time.

Efficacy of methotrexate in rheumatoid arthritis

Rheumatoid arthritis is a common inflammatory articular disorder in Bangladesh. Methotrexate has proved to be an effective and relatively safe disease modifying drug for this disease. A quasiexperimental trial of the efficacy of methotrexate in rheumatoid arthritis was carried out in the Rheumatology Clinic, Institute of Postgraduate Medicine & Research, Dhaka during the period between July 1992 and September 1993. Thirty eight patients fulfilling the revised ARA criteria were given methotrexate in a total weekly dose of 7.5 to 15 mg. They were followed up at weekly intervals for one month and then monthly for a total duration of six months. Twenty three subjects eventually completed the trial. The trial showed significant differences in the disease activity indices at the end of six months. The decline of activity was noted at the end of one month. As a whole the response was complete in 4(17%), marked in 14(61%), moderate in 4(17%) and nil in 1(4%). Adverse effects occurred in 27 subjects. They were mild and transient in 22. Methotrexate appeared to be an acceptable DMARD for our rheumatoid arthritis population.

The sheep as an animal model for heart valve research

The first test used to assess new heart valve prostheses and devices is to implant them in a medium-sized animal. This is a costly piece of research and it is important to select the most appropriate animal. The authors feel that the sheep is an appropriate animal model for heart valve research and describe their experience in this area. It is hoped that the detailed description provided will be useful to any other group contemplating similar studies.

Critical role of the sinuses of Valsalva in the durability of valved conduits

BACKGROUND AND AIMS OF THE STUDY

Most work in search of an ideal extracardiac valved conduit has assumed that the type of tissue used for construction is the determining factor for its behavior and durability. The excellent results of our study with a valved conduit incorporating sinuses of Valsalva and made of autologous pericardium showed that the design plays a crucial role in addition to the type of material.

MATERIALS AND METHODS

We report the experimental results of three different pericardial sinus bearing valved conduits made of 0.5% glutaraldehyde treated autologous pericardium (Group 1), dye mediated photooxidized bovine pericardium (Group 2), and glutaraldehyde treated bovine pericardium (Group 3) implanted in the right ventricular outflow tract of sheep. Groups 1, 2 and 3 had 11, 11 and four animals available for assessment out of 12, 18 and six implantations respectively. The valved conduits were explanted at varying intervals between one and 11 months. The conduit function was assessed with hemodynamic, echocardiographic and Doppler studies both at the time of implantation and sacrifice. The explanted conduit was studied macroscopically and subjected to histopathologic examination.

RESULTS

The hemodynamic and echocardiographic studies at implantation showed very satisfactory results in all three groups. At the time of sacrifice, Group 1 showed consistently good results. In a significant number of animals in Groups 2 and 3, one, two or even three cusps had become adherent to the conduit wall, resulting in severe regurgitation. The sinuses were well preserved in Group 1, while they were less prominent in Group 2 and least in Group 3. Histopathologically, the three groups basically showed the same feature, a process of fibrocellular proliferation resulting in thickening. In this study the adhesion of the cusps to the sinus wall was related to the degree of prominence of the sinuses of Valsalva, which in turn depended on the ability to shape the pericardium at the time of construction of the valved conduit.

CONCLUSIONS

This study stresses the importance of the sinuses in the behavior of the semilunar valve leaflets.

Comparison of fresh and glutaraldehyde-treated autologous stented pericardium as pulmonary valve replacement

The use of fresh autologous pericardium in valve surgery has shown poor results in the past mainly due to thickening and retraction. Recently, it has been suggested that a short treatment with glutaraldehyde might radically change its behavior. In an attempt to determine whether this disparity in results is due to the glutaraldehyde treatment or to a better present-day surgical technique, fresh and glutaraldehyde-treated autologous pericardium was mounted in a frame and implanted in the pulmonary position of adult sheep. Six survivors obtained in each group were sacrificed between 2 and 8 months in the "fresh" group and between 2 and 6 months in the "glutaraldehyde-treated" group. Macroscopically, the fresh pericardium became thickened and retracted in all specimens, eventually resulting in severe regurgitation, while the glutaraldehyde-treated, although slightly thickened, retained its pliability without significant retraction. Microscopically, viability of the central core of the collagen was more often preserved in the fresh pericardium. Endothelialization was irregular. In conclusion, short glutaraldehyde treatment seems to improve the results of autologous pericardium mounted on a valve stent. Its effect on calcification remains to be ascertained.

In situ mitral valve stabilization with glutaraldehyde

Mitral valve repair in the young rheumatic patient carries a high reoperation rate due to progression of the disease. In an attempt to halt or at least slow down this process, the possibility of fixing in situ the valve tissues with glutaraldehyde was explored. Six weanling sheep underwent tanning of their anterior mitral leaflet for two minutes with 0.5% buffered glutaraldehyde. The non-treated posterior mitral leaflet served as control. The animals were sacrificed at varying intervals between 2.5 and 6 months. At sacrifice, Doppler echocardiography and hemodynamic studies were done. The leaflets were subjected to histopathologic examination and calcium and glutaraldehyde contents were estimated. Glutaraldehyde treatment of the anterior leaflet caused thickening of the cusp and chordae associated with partial devitalization of its core tissue, partial loss of endothelium and intense fibrocellular reaction with abundant elastic fibers without altering its functional integrity. It did not induce calcification. There were no detectable levels of glutaraldehyde at explantation. The posterior mitral leaflets were normal. Although the absence of calcification and partial viability of the tissue are encouraging, it does not necessarily follow that this treatment would arrest progression of the underlying disease. This process may have clinical application in the future, but it is not yet recommended.

Double blind clinical trial on centperazine & DEC in bancroftian filariasis

Centperazine, an analogue of DEC, was subjected to a double blind controlled trial, to evaluate its efficacy as a newer antifilarial agent. Centperazine (300 mg/day) along with equivalent quantities of DEC and placebo were administered to different types of filariasis patients. DEC was found to be significantly effective in reducing peripheral microfilaraemia, in different weeks and months of follow-up, except at the end of 6th month, as compared to Centperazine. There was no significant difference between the placebo and Centperazine treated patients, in this respect, revealing that the drugs had no efficacy in eliminating peripheral microfilaraemia. Recurrence of acute attack within 6 months was nearly equal with both Centperazine and DEC, being 28.2 and 24 per cent respectively, whereas in the placebo group the recurrence rate was 48.9 per cent. Centperazine treated patients showed significantly less side effects (8.9%), as compared to DEC treated patients (34%). Giddiness, nausea and vomiting were the common adverse effects observed.