RD-OCT net: hybrid learning system for automated diagnosis of macular diseases from OCT retinal images.

Macular Edema is a leading cause of visual impairment and blindness in patients with ocular fundus diseases. Due to its non-invasive and high-resolution characteristics, optical coherence tomography (OCT) has been extensively utilized for the diagnosis of macular diseases. The manual detection of retinal diseases by clinicians is a laborious process, further complicated by the challenging identification of macular diseases. This difficulty arises from the significant pathological alterations occurring within the retinal layers, as well as the accumulation of fluid in the retina. Deep Learning neural networks are utilized for automatic detection of retinal diseases. This paper aims to propose a lightweight hybrid learning Retinal Disease OCT Net with a reduced number of trainable parameters and enable automatic classification of retinal diseases. A Hybrid Learning Retinal Disease OCT Net (RD-OCT) is utilized for the multiclass classification of major retinal diseases, namely neovascular age-related macular degeneration (nAMD), diabetic macular edema (DME), retinal vein occlusion (RVO), and normal retinal conditions. The diagnosis of retinal diseases is facilitated by the use of hybrid learning models and pre-trained deep learning models in the field of artificial intelligence. The Hybrid Learning RD-OCT Net provides better accuracy of 97.6% for nAMD, 98.08% for DME, 98% for RVO, and 97% for the Normal group. The respective area under the curve values were 0.99, 0.97, 1.0, and 0.99. The utilization of the RD-OCT model will be useful for ophthalmologists in the diagnosis of prevalent retinal diseases, due to the simplicity of the system and reduced number of trainable parameters.

Prenatal Evaluation of Intracranial Hemorrhage on Fetal MRI: A Retrospective Review.

BACKGROUND AND PURPOSE: The evaluation and characterization of germinal matrix hemorrhages have been predominantly described on postnatal head sonography in premature neonates. However, germinal matrix hemorrhages that are seen in premature neonates can be also seen in fetuses of the same postconceptual age and are now more frequently encountered in the era of fetal MR imaging. Our aim was to examine and describe the MR imaging findings of fetuses with intracranial hemorrhage. MATERIALS AND METHODS: A retrospective review of diagnostic-quality fetal MRIs showing intracranial hemorrhage from January 2004 to May 2020 was performed. Images were reviewed by 2 radiologists, and imaging characteristics of fetal intracranial hemorrhages were documented. Corresponding postnatal imaging and clinical parameters were reviewed. RESULTS: One hundred seventy-seven fetuses with a mean gestational age of 25.73 (SD, 5.01) weeks were included. Germinal matrix hemorrhage was identified in 60.5% (107/177) and nongerminal matrix hemorrhage in 39.5% (70/177) of patients. Significantly increased ventricular size correlated with higher germinal matrix hemorrhage grade (P < .001). Fetal growth restriction was present in 21.3% (20/94) of our population, and there was no significant correlation with germinal matrix grade or type of intracranial hemorrhage. An increased incidence of neonatal death with grade III germinal matrix hemorrhages (P = .069) compared with other grades was identified; 23.2% (16/69) of the neonates required ventriculoperitoneal shunts, with an increased incidence in the nongerminal matrix hemorrhage group (P = .026). CONCLUSIONS: MR imaging has become a key tool in the diagnosis and characterization of intracranial hemorrhage in the fetus. Appropriate characterization is important for optimizing work-up, therapeutic approach, and prenatal counseling.

Evaluation of Posterior Fossa Biometric Measurements on Fetal MRI in the Evaluation of Dandy-Walker Continuum.

BACKGROUND AND PURPOSE: Dandy-Walker malformation, vermian hypoplasia, and Blake pouch remnant represent a continuum of anomalies and are common reasons for referral for fetal MR imaging. This study aimed to determine biometric measurements that quantitatively delineate these 3 posterior fossa phenotypes. MATERIALS AND METHODS: Our single-center institutional review board approved a retrospective analysis of all fetal MRIs for posterior fossa malformations, including Dandy-Walker malformation, vermian hypoplasia, and Blake pouch remnant. Measurements included the anterior-to-posterior pons, craniocaudal and anterior-to-posterior vermis, lateral ventricle size, and tegmentovermian and posterior fossa angles. Measurements were compared with normal biometry and also between each subgroup. RESULTS: Thirty-three fetuses met the criteria and were included in the study. Seven were designated as having Dandy-Walker malformation; 16, vermian hypoplasia; and 10, Blake pouch remnant. No significant group interactions with adjusted mean gestational age for tegmentovermian and posterior fossa angles were observed. The tegmentovermian angle was significantly higher in Dandy-Walker malformation (109.5° [SD, 20.2°]) compared with vermian hypoplasia (52.13° [SD, 18.8°]) and Blake pouch remnant (32.1° [SD, 17.9°]), regardless of gestational age. Lateral ventricle sizes were significantly higher in Dandy-Walker malformation at a mean of ≥23.1 weeks' gestational age compared with vermian hypoplasia and Blake pouch remnant. The anterior-to-posterior and craniocaudal vermes were significantly smaller in Dandy-Walker malformation compared with vermian hypoplasia and Blake pouch remnant at mean of ≥23.1 weeks' gestational age. CONCLUSIONS: Dandy-Walker malformation can be described in relation to vermian hypoplasia and Blake pouch remnant by an increased tegmentovermian angle; however, other potential qualifying biometric measurements are more helpful at ≥23.1 weeks' gestational age. Because they fall along the same spectrum of abnormalities, the difficulty in distinguishing these entities from one another makes precise morphologic and biometric descriptions important.

Identification and characterization of forced degradation products of pralatrexate injection by LC-PDA and LC-MS.

Pralatrexate (PTXT) is an antineoplastic folate analog and the chemical name is (2S)-2-[[4-[(1RS)-1-[(2,4-diaminopteridin-6-yl)methyl]but-3-ynyl] benzoyl] amino] pentanedioic acid. Degradation products of PTXT drug product (DP) under different forced degradation conditions have been studied using LC-PDA and LC-MS techniques. PTXT DP was subjected to forced degradation under the conditions of hydrolysis, photolysis, oxidation, and heat in accordance with ICH guidelines. The LC-MS compatible HPLC method was developed and stressed solutions were chromatographed on reversed phase HPLC. The degradation products were monitored at a wavelength of 242nm. Stress study revealed that PTXT was sensitive towards acid, alkali, peroxide, light and heat. The degradation impurities (I-IX) were identified and characterized using LC-PDA and mass spectral data.

The impact of viral hepatitis-related hepatocellular carcinoma to post-transplant outcomes.

Hepatocellular carcinoma (HCC) is the most common complication of HCV infection leading to liver transplantation. We evaluated the impact of aetiology of liver disease on patient and graft survival following liver transplantation for HCC. From the Scientific Registry of Transplant Recipients (2002-2011), all adults who underwent liver transplantation for HCC were retrospectively included. Aetiology of liver disease was grouped into HCV, HBV, HCV-HBV co-infection and nonviral liver disease. Of 8,733 liver transplant recipients with HCC, 5507 had HCV, 631 had HBV, 163 were co-infected, and 2432 had nonviral causes of liver disease. In follow-up (48 ± 32 months), 8.2% had graft failure and 29.5% died. The mean rates of graft failure were 9.5%, 4.7%, 6.1% and 6.4% in HCV, HBV, HCV-HBV co-infection and nonviral liver disease, respectively (P < 0.0001). Post-transplant mortality rate in patients with HBV was 20.2%, HCV 31.0%, HCV-HBV 28.5% and nonviral 28.5% (P < 0.0001). This difference was significant starting one year post-transplant and became even more prominent later in follow-up. Five-year post-transplant survival was 64.7% in HCV, 77.7% in HBV, 71.0% in HCV-HBV and 69.1% in nonviral HCC (P < 0.0001). A diagnosis of HCV in patients with HCC was also independently associated with an increased risk of both graft failure (adjusted hazard ratio = 1.84 (1.46-2.33), P < 0.0001) and mortality (1.35 (1.21-1.50), P < 0.0001) in multivariate analysis. Patients with HCV-related HCC are at higher risk of adverse post-transplant outcomes. These patients should be considered for preemptive interferon-free antiviral therapy prior to or immediately following liver transplantation.

Inpatient resource utilization, disease severity, mortality and insurance coverage for patients hospitalized for hepatitis C virus in the United States.

Although the incidence of new hepatitis C virus (HCV) infection has fallen, HCV-related complications are on the rise. Our aim was to assess and describe the 2005-2009 national inpatient mortality and resource utilization trends for patients with HCV. Data from the National Inpatient Sample (NIS) and the National Hospital Discharge Survey (NHDS) between 2005 and 2009 were analyzed. Included were all adult hospital discharges with HCV-related ICD-9 codes. Incremental hospital charge, in-hospital mortality and length of stay (LOS) were estimated using n = 1000 bootstrap replicates clustered by unique hospital identifier. A total of 123 939 (0.38%) discharges were related to HCV (primary or secondary diagnosis). In-hospital mortality increased from 1.7% (2005) to 2.6% (2009) (P < 0.001). Inflation-adjusted charges increased 2% annually from 2005 ($16 455 ± $570) to 2009 ($17 532 ± $1007, P = 0.029). This increase occurred despite the average LOS (5 days) and hospital costs ($6500) remaining stable while at the same time, hospital-to-hospital transfer admissions and disposition to home health care increased. HCV-related hepatocellular carcinoma predicted longer hospital stay and death; older age predicted death; and receiving more procedures predicted higher hospital costs. The percentage of patients with private insurance significantly decreased (4.7%), while government-sponsored insurance and uninsured increased by 2.5% and 2.1%, respectively (P < 0.05). Uninsured patients had a 49%-72% greater chance of dying during hospitalization than those with government-sponsored insurance. HCV-related inpatient mortality and resource utilization have increased. HCC was the largest predictor for mortality and resource utilization. These data are consistent with the rising clinical and societal burden of chronic hepatitis C in the United States.

Cytotoxicity, genotoxicity and oxidative stress of malachite green on the kidney and gill cell lines of freshwater air breathing fish Channa striata.

The cytotoxicity, genotoxicity and oxidative stress of malachite green (MG) was investigated using the fish Channa striata kidney (CSK) and Channa striata gill (CSG) cell lines. Five concentrations ranging from 0.001 to 10 µg mL(-1) were tested in three independent experiments. Cytotoxicity was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Rhodamine 123 and Alamar Blue. The mitochondrial changes and apoptosis of MG-exposed cells were observed by Rhodamine 123 and acridine orange/ethidium bromide (AO/EB) staining, respectively. In vitro potential DNA damaging effect of MG was tested using comet assay. Mitochondrial damage, apoptosis and DNA fragmentation increased in a concentration-dependent manner. Additionally, DNA electrophoretic mobility experiments were carried out to study the binding effect of MG to double-stranded DNA (dsDNA) of cells. DNA shift mobility experiments showed that MG is capable of strongly binding to linear dsDNA causing its degradation. Biochemical parameters such as lipid peroxidation (MDA), catalase (CAT) activity and reduced glutathione (GSH) levels were evaluated after exposure to MG. In CSK and CSG cell lines exposed to MG for 48 h, a significant increase in lipid peroxidation, which might be associated with decreased levels of reduced glutathione and catalase activity in these cell lines (p < 0.001), was observed.

Neutralization of cobra venom by cocktail antiserum against venom proteins of cobra (Naja naja naja).

Naja naja venom was characterized by its immunochemical properties and electrophoretic pattern which revealed eight protein bands (14 kDa, 24 kDa, 29 kDa, 45 kDa, 48 kDa, 65 kDa, 72 kDa and 99 kDa) by SDS-PAGE in reducing condition after staining with Coomassie Brilliant Blue. The results showed that Naja venom presented high lethal activity. Whole venom antiserum or individual venom protein antiserum (14 kDa, 29 kDa, 65 kDa, 72 kDa and 99 kDa) of venom could recognize N. naja venom by Western blotting and ELISA, and N. naja venom presented antibody titer when assayed by ELISA. The neutralization tests showed that the polyvalent antiserum neutralized lethal activities by both in vivo and in vitro studies using mice and Vero cells. The antiserum could neutralize the lethal activities in in-vivo and antivenom administered after injection of cobra venom through intraperitoneal route in mice. The cocktail antiserum also could neutralize the cytotoxic activities in Vero cell line by MTT and Neutral red assays. The results of the present study suggest that cocktail antiserum neutralizes the lethal activities in both in vitro and in vivo models using the antiserum against cobra venom and its individual venom proteins serum produced in rabbits.

Detection and neutralization of cobra venom using rabbit antiserum in experimental envenomated mice.

A sandwich enzyme-linked immunosorbent assay (ELISA) was developed to detect the venom of Indian cobra (Naja naja naja) in various tissues (brain, heart, lungs, liver, spleen, blood, kidneys, and tissue at the site of injection) of mice after cobra venom injected at different time intervals (0, 2, 4, 6, 8, and 12 h intervals up to 24 h). Whole venom antiserum or individual venom protein antiserum (14, 29, 65, 72, and 99 kDa) could recognize N. n. naja venom by Western blotting and ELISA, and antibody titer was also assayed by ELISA. Antiserum raised against cobra venom in rabbit significantly neutralized the toxicity of venom-injected mice at different time intervals after treatment. The assay could detect N. n. naja venom levels up to 2.5 ng/ml of tissue homogenate, and the venom was detected up to 24 h after venom injection. Venom was detected in brain, heart, lungs, liver, spleen, kidneys, tissue at the bite area, and blood. As observed in mice, tissue at the site of bite area showed the highest concentration of venom and the brain showed the least. Moderate amounts of venoms were found in liver, spleen, kidneys, heart, and lungs. Development of a simple, rapid, and species-specific diagnostic kit based on this ELISA technique useful to clinicians is discussed.

Antivenom activity of triterpenoid (C34H68O2) from Leucas aspera Linn. against Naja naja naja venom induced toxicity: antioxidant and histological study in mice.

The isolated and identified triterpenoid, 1-hydroxytetratriacontane-4-one (C34H68O2), obtained from the methanolic leaf extract of Leucas aspera Linn. was explored for the first time for antisnake venom activity. The plant (L. aspera Linn.) extract significantly antagonized the spectacled cobra (Naja naja naja) venom induced lethal activity in a mouse model. It was compared with commercial antiserum obtained from King Institute of Preventive Medicine (Chennai, Tamil Nadu, India). N. naja naja venom induced a significant decrease in antioxidant superoxide dismutase, glutathione (GSH) peroxidase, catalase, reduced GSH and glutathione-S-transferase activities and increased lipid peroxidase (LPO) activity in different organs such as heart, liver, kidney and lungs. The histological changes following the antivenom treatment were also evaluated in all these organs. There were significant alterations in the histology. Triterpenoid from methanol extract of L. aspera Linn. at a dose level of 75 mg per mouse significantly attenuated (neutralized) the venom-induced antioxidant status and also the LPO activity in different organs.

The impact of chronic hepatitis C on resource utilisation and in-patient mortality for Medicare beneficiaries between 2005 and 2010.

BACKGROUND: As baby boomers age, chronic hepatitis C (CHC) will become increasingly important in Medicare eligible group. AIM: To evaluate trends in Medicare resource utilisation for CHC. METHODS: We analysed the Medicare in-patient and out-patient data from 2005 to 2010. For each patient, all claims with CHC as a principal diagnosis were added up and yearly CHC-related spending was calculated. RESULTS: A total of 48,880 out-patient claims for 21,655 CHC patients and 4884 hospital admission claims for 3092 patients were included. The number of in-patient (1.5-1.6/year) or out-patient (2.2-2.3/year) visits per patient did not change over time, nor did the demographic characteristics of the CHC population. The majority of this population was eligible for Medicare based on disability and the average number of diagnoses per in-patient claim (from 8.11 in 2005 to 8.60 in 2010) and per out-patient claim (from 2.18 in 2005 to 2.71 in 2010) increased (both P < 0.0001). The average total yearly spending per patient increased in the out-patient setting from $488 in 2005 to $584 in 2010 (P = 0.0132) and did not change in the in-patient setting (from $22,245 in 2005 to $23,383 in 2010, P = 0.14). In the multivariate analysis, the number of diagnoses and conditions per claim and the number of in-patient or out-patient procedures per year were the important independent predictors of increased resource utilisation. CONCLUSIONS: Most Medicare beneficiaries with chronic hepatitis C who sought in-patient or out-patient care in 2005-2010 had received Medicare for disability. Although the total resource utilisation did not change, the proportion of patient's responsibility increased.

Synthesis and characterization of chitosan tripolyphosphate nanoparticles and its encapsulation efficiency containing Russell's viper snake venom.

Chitosan Tripolyphosphate (CS/TPP) nanoparticle is a biodegradable and nontoxic polysaccharide, used as a carrier for drug delivery. The morphology and particle-size measurements of the nanoparticles were studied by field emission scanning electron microscopy and Fourier Transform Infrared Spectroscopy (FTIR). This study aims to evaluate the impact of Russell's viper venom encapsulation on various factors and loading capacity, in addition to explore the physicochemical structure of nanoparticles. FTIR confirmed that tripolyphosphoric groups of TPP linked with ammonium groups of CS in the nanoparticles. Our results showed that CS can react with TPP to form stable cationic nanoparticles. The results also showed that encapsulation efficiency of venom at different concentrations of 20, 40, 60, 500, and 1000 µg/mL were achieved for CS/TPP nanoparticles at different concentrations of 1.5, 2, and 3 mg/mL. The cytotoxicity of CS/TPP nanoparticles was evaluated by MTT (-3 (4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a tetrazole) assay.

Moderate, excessive or heavy alcohol consumption: each is significantly associated with increased mortality in patients with chronic hepatitis C.

BACKGROUND: The impact of moderate alcohol consumption on long-term outcomes of chronic hepatitis C (CH-C) infected patients remains controversial. AIM: To assess the impact of moderate alcohol consumption on long-term outcomes of CH-C patients using population-based data. METHODS: Data were obtained from the Third National Health and Nutrition Examination Survey (NHANES III)-mortality linked files. Alcohol consumption was estimated as grams/day. Multivariate Cox proportional hazards model was utilized to assess the effects of CH-C and alcohol consumption on mortality (all causes, cardiovascular disease, and liver disease). RESULTS: A total of 8985 participants were included as the study cohort. Of these, 218 had CH-C. The follow-up time was 162.95 months for CH-C and 178.27 months for controls. CH-C patients had increased risk for both overall mortality and liver-related mortality. CH-C patients with excessive alcohol consumption had even higher risks for overall mortality and liver-related mortality. The risk of overall mortality associated with CH-C increased with moderate alcohol consumption of 1-19 g/day and heavy alcohol consumption ≥30 g/day. CONCLUSION: Although chronic hepatitis C is associated with increased risks for overall and liver-related mortality, these risks are even higher for patients consuming moderate and excessive amounts of alcohol.

A 2012 clinical update for internists in adult nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the Western world. Associated with the metabolic syndrome, NAFLD is associated with adverse cardiovascular outcomes. A subset of NAFLD patients with histologic nonalcoholic steatohepatitis (NASH) can have increased liver related mortality. Because of the prevalence and complications of this chronic liver disease, it is important that internists understand important aspects about diagnosis and management. In this article, we aim to provide an update to clinicians related to issues surrounding prognosis, monitoring, and treatment.

Experimental exposure of Artemia to hepatopancreatic parvo-like virus and subsequent transmission to post-larvae of Penaeus monodon.

The different life stages of Artemia franciscana were experimentally exposed to Hepatopancreatic parvo-like virus (HPV), in order to evaluate the possibility of Artemia acting as reservoir or carrier for HPV. All the five developmental stages of Artemia were challenged with HPV both by immersion and oral infection routes. The viral infectivity to Artemia was studied by PCR but not much difference in mortality between control and challenge groups were observed. To confirm the vector status of Artemia for HPV, the HPV exposed Artemia were fed to postlarval forms of Penaeus monodon. Post-larvae of P. monodon were fed with HPV exposed Artemia and could get infected upon feeding on them. Mortality was observed in the post-larvae, which were fed with HPV exposed Artemia, and whereas no mortality was observed in post-larvae fed with Artemia not exposed to HPV and these post-larvae were PCR negative for HPV, as well. Results of this experiment suggest that Artemia might be a possible horizontal transmission pathway for HPV. Further research however is required with histology, immunohistochemistry and transmission electron microcopy to determine whether the Artemia are actually infected with this virus or whether they are simply mechanical carriers. This will enable us to understand better whether Artemia is a carrier of this virus and if so the mechanism involved.

Oral delivery of DNA construct using chitosan nanoparticles to protect the shrimp from white spot syndrome virus (WSSV).

The protective efficacy of oral delivery of a DNA construct containing the VP28 gene of WSSV encapsulated in chitosan nanoparticles was investigated in black tiger shrimp (Penaeus monodon). The results showed that significant survival was obtained in WSSV-challenged shrimp at 7, 15 and 30 days post-treatment (relative survival, 85%, 65% and 50%, respectively) whereas 100% mortality was observed in the control shrimp fed with feed containing chitosan/pcDNA 3.1 or chitosan/PBS complex. The ability of the chitosan to form a complex with the pVP28 and to stabilize it from endonuclease degradation was studied by agarose gel electrophoresis. Cytotoxicity of chitosan-encapsulated pVP28 was also evaluated by the MTT assay, which showed 90% viability of SISK cells incubated with the pVP28/chitosan complexes. Transcription analysis of the chitosan-encapsulated pVP28 gene in different tissues of DNA-treated shrimp and SISK cell line was confirmed by an RT-PCR reaction. The present study also measured the changes in the level of important immunological parameters such as prophenoloxidase, superoxide dismutase and superoxide anion in hemolymph of chitosan-encapsulated VP28 DNA-treated and controls shrimp. The study also correlated the changes in the level of immunological parameters with the survival percentage and protective efficacy of oral route of DNA construct against WSSV in shrimp.

Laboratory study on larvicidal activity of indigenous plant extracts against Anopheles subpictus and Culex tritaeniorhynchus.

Anopheles subpictus and Culex tritaeniorhynchus have developed resistance to various synthetic insecticides, making its control increasingly difficult. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The leaf acetone, chloroform, ethyl acetate, hexane, and methanol extracts of Aegle marmelos (Linn.) Correa ex Roxb, Andrographis lineata Wallich ex Nees., Andrographis paniculata (Burm.f.) Wall. ex Nees., Cocculus hirsutus (L.) Diels, Eclipta prostrata L., and Tagetes erecta L. were tested against fourth-instar larvae of malaria vector, A. subpictus Grassi and Japanese encephalitis vector, C. tritaeniorhynchus Giles (Diptera: Culicidae). All plant extracts showed moderate larvicidal effects after 24 h of exposure at 1,000 ppm; however, the highest larval mortality was found in leaf ethyl acetate of A. marmelos, E. prostrata, hexane, methanol of A. paniculata and C. hirsutus against the larvae of A. subpictus (LC(50) = 167.00, 78.28, 67.24, 142.83 ppm; LC(90) = 588.31, 360.75, 371.91, and 830.01 ppm) and against the larvae of C. tritaeniorhynchus (LC(50) = 99.03, 119.89, 88.50, 105.19 ppm; LC(90) = 479.23, 564.85, 416.39, and 507.86 ppm), respectively. These results suggest that the leaf hexane extract of A. paniculata and ethyl acetate extract of E. prostrata have the potential to be used as an ideal eco-friendly approach for the control of the A. subpictus and C. tritaeniorhynchus. Therefore, this study provides first report on the mosquito larvicidal activity of plant extracts against vectors from Southern India.

Studies on the immunomodulatory effect of extract of Cyanodon dactylon in shrimp, Penaeus monodon, and its efficacy to protect the shrimp from white spot syndrome virus (WSSV).

The present study investigates the protection of shrimp Penaeus monodon against white spot syndrome virus (WSSV) using antiviral plant extract derived from Cyanodon dactylon and the modulation of the shrimp non-specific immunity. To determine the antiviral activity, the shrimp were treated by both in vitro (intramuscular injection) and in vivo (orally with feed) methods at the concentration of 2mg per animal and 2% of the plant extract incorporated with commercially available artificial pellet feed, respectively. The antiviral activity of C. dactylon plant extract was confirmed by PCR, bioassay and Western blot analysis. In the present study, anti-WSSV activity of C. dactylon plant extract by in vivo and in vitro methods showed strong antiviral activity and the immunological parameters such as proPO, O(2)(-), NO, THC and clotting time were all significantly (P<0.05) higher in the WSSV-infected shrimp treated with plant extract when compared to control groups. These results strongly indicate that in vivo and in vitro administration of C. dactylon plant extract enhances immunity of the shrimp. Based on the present data and the advantages of plant extract available at low price, we believe that oral administration of C. dactylon plant extract along with the pellet feed is a potential prophylactic agent against WSSV infection of shrimp.

Clearance of white spot syndrome virus (WSSV) and immunological changes in experimentally WSSV-injected Macrobrachium rosenbergii.

A time course experimental challenge of WSSV was carried out to examine the clearance of WSSV in Macrobrachium rosenbergii and the consequent immunological changes. The experimental animals were injected with WSSV and the samples of gills, pleopods, head soft tissue and hemolymph were collected at different intervals of 1, 3, 5, 10, 25, 50, 75 and 100 days post infection (p.i.). WSSV infection and clearing were confirmed by single step PCR, nested PCR and bioassay. At 3 days p.i., M. rosenbergii became lethargic and stopped feeding in contrast to the control prawns that behaved and fed normally. However, the WSSV-injected prawns suffered no mortality during the experimental period and recovered without any further gross signs of disease or any mortality over a period of 100 days p.i. The single step PCR analysis showed positive at 1, 3 and 5 days p.i. in gills, head soft tissue, pleopods and hemolymph, and all the organs showed negative at 10 days p.i. onwards. The nested PCR results showed that all organs were positive for WSSV from 3 days p.i. and extended up to 25 days p.i. At 50 days p.i, head soft tissue sample alone showed WSSV-positive while all other organs were negative by nested PCR. All the organs at 75 and 100 days p.i. showed nested PCR negative for WSSV as observed in the control prawn. The hemolymph collected from experimentally infected M. rosenbergii at 1, 3 and 5 days p.i. caused 100% mortality at 40 h p.i., 55 h p.i. and 72 h p.i, respectively in Penaeus monodon whereas hemolymph collected at 10, 25, 50, 75 and 100 days p.i. failed to cause mortality in shrimp. The moribund shrimp showed WSSV-positive and surviving shrimp showed negative by PCR. Immunological parameters such as proPO, O(2)(-) and clotting time in WSSV-injected M. rosenbergii were found to be significantly higher than those of the control groups, whereas THC and superoxide dismutase were significantly lower when compared to control groups.