27 research outputs found
Anesthesia for Intraocular Surgery in Rabbits
The purpose of the study was to assess a ketamine/xylazine combination along with retrobulbar block using 4% lignocaine HCl for performing intraocular surgery in rabbits. To do so ten healthy adult New Zealand White rabbits aged 1.5-2 years of either sex weighing 2-3 kgs were selected for unilateral cataract extraction by phacoemulsification . Xylazine HCl was used as preanesthetic at a dose rate of 5 mg/kg, i.m., followed by Ketamine HCl at a dose rate of 35mg/kg, i.m. A retro bulbar block was performed with 4% lignocaine HCL. The anesthetic depth was judged by ear pinching reflex. The time for onset and duration of anesthesia was found to be 7±0.5 minutes and 35.5±1.2 minutes respectively. A central eyeball fixation following retro bulbar block was obtained in all the cases. The mean values recorded before induction of anesthesia and during anesthesia of rectal temperature (38.090C±0.2 vs. 37.290C±0.2), heart rate in beats per minute (276±1.2 vs.272±1.1), arterial blood pH (7.35±0.02 vs. 7.32±0.02), bicarbonate (16.2±1.2 vs. 20.3±1.8), PaCo2 (26.09±2.3 vs. 27.52±2.3) and PaO2 (84.79±1.9 vs. 80.39±1.1) did not vary significantly (P>0.05). Recovery was smooth and complete in 32.5±2.8 minutes. Conclusion: the anesthetic regimen provides adequate condition for conducting intraocular surgery in rabbits.
Non-mulberry Silk Fibroin Biomaterial for Corneal Regeneration
Successful repair of a damaged corneal surface is a great challenge and may require the use of a scaffold that supports cell growth and differentiation. Amniotic membrane is currently used for this purpose, in spite of its limitations. A thin transparent silk fibroin film from non-mulberry Antheraea mylitta (Am) has been developed which offers to be a promising alternative. The silk scaffolds provide sufficient rigidity for easy handling, the scaffolds support the sprouting, migration, attachment
and growth of epithelial cells and keratocytes from rat corneal explants; the cells form a cell sheet,
preserve their phenotypes, express cytokeratin3 and vimentin respectively. The films also support growth of limbal stem cell evidenced by expression of ABCG2. The cell growth on the silk film and the amniotic membrane is comparable. The implanted film within the rabbit cornea remains transparent, stable. The clinical examination as well as histology shows absence of any inflammatory response or neovascularization. The corneal surface integrity is maintained; tear formation, intraocular pressure and electroretinography of implanted eyes show no adverse changes. The silk fibroin film from nonmulberry
silk worms may be a worthy candidate for use as a corneal scaffold
Estimating the burden of malaria in pregnancy: a case study from rural Madhya Pradesh, India
BACKGROUND: Malaria in pregnancy (MiP) is inadequately researched in India, and the burden is probably much higher than current estimates suggest. This paper models the burden of MiP and associated foetal losses and maternal deaths, in rural Madhya Pradesh, India. METHODS: Number of pregnancies per year was estimated from the number of births and an estimate of pregnancies that end in foetal loss. The prevalence of MiP, risk of foetal loss attributable to MiP and case fatality rate of MiP were obtained from the literature. The estimated total number of pregnancies was multiplied by the appropriate parameter to estimate the number of MiP cases, and foetal loss and maternal deaths attributable to MiP per year. A Monte Carlo simulation sensitivity analysis was done to assess plausibility of various estimates obtained from the literature. The burden of MiP in tribal women was explored by incorporating the variable prevalence of malaria in tribal and non-tribal populations and in forested and non-forested regions within Madhya Pradesh. RESULTS: Estimates of MiP cases in rural Madhya Pradesh based on the model parameter values found in the literature ranged from 183,000-1.5 million per year, with 73,000-629,000 lost foetuses and 1,500-12,600 maternal deaths attributable to MiP. The Monte Carlo simulation gave a more plausible estimate of 220,000 MiP cases per year (inter-quartile range (IQR): 136,000-305,000), 95,800 lost foetuses (IQR: 56,800-147,600) and 1,000 maternal deaths (IQR: 650-1,600). Tribal women living in forested areas bore 30% of the burden of MiP in Madhya Pradesh, while constituting 18% of the population. CONCLUSION: Although the estimates are uncertain, they suggest MiP is a significant public health problem in rural Madhya Pradesh, affecting many thousands of women and that reducing the MiP burden should be a priority
Pirfenidone nanoparticles improve corneal wound healing and prevent scarring following alkali burn.
To evaluate the effects of pirfenidone nanoparticles on corneal re-epithelialization and scarring, major clinical challenges after alkali burn.Effect of pirfenidone on collagen I and α-smooth muscle actin (α-SMA) synthesis by TGFβ induced primary corneal fibroblast cells was evaluated by immunoblotting and immunocytochemistry. Pirfenidone loaded poly (lactide-co-glycolide) (PLGA) nanoparticles were prepared, characterized and their cellular entry was examined in primary corneal fibroblast cells by fluorescence microscopy. Alkali burn was induced in one eye of Sprague Dawley rats followed by daily topical treatment with free pirfenidone, pirfenidone nanoparticles or vehicle. Corneal re-epithelialization was assessed daily by flourescein dye test; absence of stained area indicated complete re-epithelialization and the time for complete re-epithelialization was determined. Corneal haze was assessed daily for 7 days under slit lamp microscope and graded using a standard method. After 7 days, collagen I deposition in the superficial layer of cornea was examined by immunohistochemistry.Pirfenidone prevented (P<0.05) increase in TGF β induced collagen I and α-SMA synthesis by corneal fibroblasts in a dose dependent manner. Pirfenidone could be loaded successfully within PLGA nanoparticles, which entered the corneal fibroblasts within 5 minutes. Pirfenidone nanoparticles but not free pirfenidone significantly (P<0.05) reduced collagen I level, corneal haze and the time for corneal re-epithelialization following alkali burn.Pirfenidone decreases collagen synthesis and prevents myofibroblast formation. Pirfenidone nanoparticles improve corneal wound healing and prevent fibrosis. Pirfenidone nanoparticles are of potential value in treating corneal chemical burns and other corneal fibrotic diseases
Molecular characterization of Echinococcus granulosus of Indian animal isolates on the basis of nuclear and mitochondrial genotype
Sixty-six isolates of larval stage of Echinococcus
granulosus, a known pathogenic parasite of man
and animals were collected from cattle, buffalo, sheep, and
goats. Single-stranded conformation polymorphism (SSCP)
for analysis of variation after denaturation of amplicon of
intron of actin II (ACTII) revealed six SSCP phenotypes.
Intron portion was analyzed considering introns-early and
introns-late theories. Isolates belonging to different conformers
were further screened for mitochondrial ATPase
subunit 6 (ATP6) and NADH dehydrogenase subunit II
(nadII) genotypes. Assignment of each isolate to its specific
strain was achieved after comparing with standard
genotypes of E. granulosus. Variants deduced by nuclear
targets did not match with mitochondrial haplotypes. A
possible explanation for this observation can be attributed
toward interspecific hybridization since cross-fertilization
occurs less frequently in hermaphrodite organisms. A
phylogenetic tree drawn on the basis of predicted aminoacid
sequence of ATP6 and nadII revealed two distinct clusters i.e. E. granulosus sensu stricto and E. ortleppi/
cattle strain (EG5). To the best of our knowledge, this is the
first report of genetic characterization of two distinct ATP6
and nadII genotypes of zoonotic importance living in
sympatry
Excess of Glucocorticoid Induces Cardiac Dysfunction via Activating Angiotensin II Pathway
Background: Glucocorticoid is widely used as an
anti-inflammatory drug in various diseases however
excess of it often causes cardiovascular
complications. The present study was undertaken to
understand the molecular mechanism of
glucocorticoid-induced cardiac dysfunction. Methods:
Rats were treated daily with synthetic glucocorticoid,
dexamethasone with or without mifepristone or
losartan up to 15 days. Hemodynamic parameters
were measured by PV-loop method using Millar’s
instrument. Cardiac remodelling, fibrosis and oxidative
stress were monitored after 15 days. Results: The
systolic blood pressure was increased whereas the
heart beat and cardiac output (n=6) were decreased
by dexamethasone. Dexamethasone caused increase
in the heart weight to body weight ratio (P<0.001,
n=20), increased level of mRNA of atrial natriuretic
peptide and an increased deposition of collagens in
the extracellular matrix of the left ventricle which were
inhibited by both mifepristone and losartan. The rate of oxygen consumption was decreased in association
with increased levels of hypoxia inducible factor
Analysis of differentially expressed genes in hyperthyroid-induced hypertrophied heart by cDNA microarray
Experiments were carried out to identify the altered genes
in hyperthyroid rat heart and their influence on the
functions of cardiac myocytes. Chronic treatment of rats
with 3,5,3_ triiodo-Ç¿-thyronine (T3) resulted in a prominent
increase in the size of the left ventricle with increased
wall thickness and reduced chamber volume leading to
concentric cardiac hypertrophy. The heart weight to body
weight ratio (HW/BW) in hyperthyroid rats was increased
by about 58% over that of normal rats. Using cDNA
microarray comprising 588 genes, we compared the differences
in mRNA expression of hyperthyroid and normal
rat heart. Based on a threshold of greater than 10% change,
about 37 genes were found to be regulated by T3. Further
analyses by Western blotting, Northern blotting and
real-time quantitative RT-PCR of some of the genes
confirmed the microarray results. The T3-altered genes
encode various types of proteins related to metabolism,
matrix and cytoskeletal structures, growth factors, transcription
factors, Ca2+-channels etc. The physiological
significance of one of these altered proteins in hyperthyroid
heart, insulin-responsive glucose transporter (GLUT)
type 4 (GLUT4), was studied in detail. The expression of
GLUT4 was drastically reduced in the ventricular tissues
of hyperthyroid heart. Insulin-induced glucose uptake in
hyperthyroid cardiomyocytes was reduced significantly,
indicating the impaired glucose transport in cardiac cells.
Interestingly, a few genes such as GLUT4, cytochrome
P450 isoforms, superoxide dismutase (SOD), collagens,
matrix metalloproteinases (MMP), tissue inhibitors of
matrix metalloproteinases etc. which had not been
reported earlier were found to be altered in hyperthyroid
heart. Our results show some new aspects of hyperthyroid
heart which will be important in assessing the
pathophysiology of hypertrophied cardiomyocytes
Molecular characterization of Echinococcus granulosus of Indian animal isolates on the basis of nuclear and mitochondrial genotype
clusters i.e. E. granulosus sensu stricto and E. ortleppi/
cattle strain (EG5). To the best of our knowledge, this is the
first report of genetic characterization of two distinct ATP6
and nadII genotypes of zoonotic importance living in
sympatr
Collagen 1 expression was reduced in the pirfenidone NP treated cornea: Immunohistochemistry shows increased expression of collagen I in the superficial layer of corneas from control and free pirfenidone treated rats, and a reduced expression in the corneas from pirfenidone NP treated rats.
<p>Corresponding DAPI stained sections are also presented.</p