Awareness and perception of contact lens usage and refractive surgery among first year undergraduate medical students

Background: Refractive error occurs when the parallel rays of light coming from infinity are focused either in front or behind the retina, in one or both the meridians resulting in blurred image. The purpose of this study is to assess the level of awareness and perception of contact lens usage and refractive surgery among first year undergraduate medical students. Methods: A cross sectional, observational questionnaire-based study was done on students studying in Saveetha medical college near Sriperumbudur between February 2021 to April 2021 to assess student’s awareness and perception of contact lens usage and refractive surgery. Results: Totally 250 students were studied, of which 39.76% were under 20 years, 61.85% are not contact lens users, 51.41% think that appropriate time of wearing contact lens was 8 hours per day, 64.66% think that soft contact lens should be used, 70.28% think that contact lens should be renewed every 3 months, 38.96% are not aware of refractive surgery, 54.62% think that dry eye is the complication of long term usage of contact lens, 44.18% think that contact lens are required even after surgery, 38.55% think that there will be complications even after refractive error surgery. Conclusions: The awareness of knowledge, attitude and practice regarding contact lenses usage and refractive surgery was evaluated among the participants to identify the points of weakness and construct a proper health education among the students.

Characterization, In Vitro Antioxidant And Hepatoprotective Activity Of Fungal Endophytic Extracts Of Andrographis Paniculata Leaves In Ccl4 Induced Hepatotoxicity

Objective: To isolate and characterize the endophytic fungi from the leaves of Andrographis paniculata for free radical scavenging antioxidant and hepatoprotective activity against CCl4 induced hepatotoxicity Methods: Two fungal endophytes, APLF-3 (Andrographis paniculata leaf fungi-3) and APLF-4 (Andrographis paniculata leaf fungi-4) were isolated from leaves of Andrographis paniculata to get chloroform (A3C, A4C), ethyl acetate (A3EA, A4EA) and n butanol (A3nB, A4nB) extracts. rDNA sequencing by PCR technique was carried out for identification of APLF-3 and APLF-4. All the APLF-3 and APLF-4 extracts were assayed for in vitro free radical scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical and reducing power. Then, A4EA and A4nB were screened for hepatoprotective activity against CCl4 induced hepatotoxicity at 50 mg/kg and100 mg/kg doses. Results: The endophytic fungi, APLF-3 and APLF-4, were identified as Phyllosticta sp. ZLY-2010 isolate M13 and Aspergillus tubingensis strain Cs/7/2 respectively based on their morphological and molecular characterization. A4EA and A4nB showed significant in vitro free radical scavenging activity as compared to other extracts. A4EA and A4nB (50 mg/kg and100 mg/kg) reversed the increased serum biochemical parameters as compared to CCl4 treated group (p<0.001). A4EA and A4nB (100 mg/kg p. o) also restored the LPO, SOD and CAT levels. Conclusion: These findings suggested that the extracts (A4EA and A4nB) obtained from endophytic fungi APLF-4 contributed towards hepatoprotective activity.

Biochemical and immunological characterization of E. coli expressed 42 kDa fragment of Plasmodium vivax and P. cynomolgi bastianelli merozoite surface protein-1.

Plasmodium vivax is one of the most widely distributed human malaria parasites and due to drug-resistant strains, its incidence and prevalence has increased, thus an effective vaccine against the parasites is urgently needed. One of the major constraints in developing P. vivax vaccine is the lack of suitable in vivo models for testing the protective efficacy of the vaccine. P. vivax and P. cynomolgi bastianelli are the two closely related malaria parasites and share a similar clinical course of infection in their respective hosts. The merozoite surface protein-1 (MSP-1) of these parasites has found to be protective in a wide range of host-parasite systems. P. vivax MSP-1 is synthesized as 200 kDa polypeptide and processed just prior to merozoite release from the erythrocytes into smaller fragments. The C- terminal 42 kDa cleavage product of MSP-1 (MSP-1(42)) is present on the surface of merozoites and a major candidate for blood stage malaria vaccine. In the present study, we have biochemically and immunologically characterized the soluble and refolded 42 kDa fragment of MSP-1 of P. vivax (PvMSP-1(42)) and P. cynomolgi B (PcMSP-1(42)). SDS-PAGE analysis showed that both soluble and refolded E. coli expressed P. vivax and P. cynomolgi B MSP-1(42) proteins were homogenous in nature. The soluble and refolded MSP-1(42) antigens of both parasites showed high reactivity with protective monkey sera and conformation-specific monoclonal antibodies against P. cynomolgi B and P. vivax MSP-1(42) antigens. Immunization of BALB/c mice with these antigens resulted in the production of high titres of cross-reactive antibodies primarily against the conformational epitopes of MSP-1(42) protein. The immune sera from rhesus monkeys. immunized with soluble and refolded MSP-1(42) antigens of both parasites also showed high titered cross-reactive antibodies against MSP-1(42) conformational epitopes. These results suggested that the soluble and refolded forms of E. coli expressed P. vivax MSP-1(42) antigens were highly immunogenic and thus a viable candidate for vaccine studies.

Time course of in vitro maturation of intra-erythrocytic malaria parasite: a comparison between Plasmodium falciparum and Plasmodium knowlesi

The schizont maturation assay for in vitro drug sensitivity tests has been a standard method employed in the global baseline assessment and monitoring of drug response in Plasmodium falciparum. This test is limited in its application to synchronous plasmodial infections because it evaluates the effect of drug on the maturation of parasite especially from ring to schizont stage and therefore synchronized P. falciparum cultures are required. On the other hand, P. knowlesi, a simian malaria parasite has a unique 24-h periodicity and maintains high natural synchronicity in monkeys. The present report presents the results of a comparative study on the course of in vitro maturation of sorbitol synchronized P. falciparum and naturally synchronous P. knowlesi. Ring stage parasites were incubated in RPMI medium supplemented with 10-15 percent pooled homologous serum in flat-bottomed 96-well micro plates using a candle jar at 37°C. The results suggest that the ideal time for harvesting the micro-assay plates for in vitro drug sensitivity test for sorbitol-synchronized P. falciparum and naturally synchronous P. knowlesi are from 26 to 30 h and from 22 to 25 h, respectively. The advantages of using P. knowlesi in chemotherapeutic studies are discussed

Ultrasonographic evaluation of common duct diameter in pre and post cholecystectomy patients.

Thirty four patients with gall bladder disease and normal common duct were investigated prospectively by ultrasonography just before cholecystectomy and at periodic intervals of 1 months, 2 months, 3 months and once in 4-6 months after cholecystectomy. The pre and post cholecystectomy common duct diameters were measured at each visit and compared with each other to determine the statistical significance. No significant change (p > 0.05) occurred in common duct diameter following cholecystectomy.

AIDS cholangiopathy.

A 45-year-old man presented with diarrhea and profound weight loss over one year. His serum alkaline phosphatase was raised and ultrasonography showed dilated intrahepatic biliary ducts and upper part of common bile duct (CBD). ERCP showed papillary stenosis, dilated CBD, stricture at the confluence and saccular dilatation of the left intrahepatic biliary ducts. He was found HIV-positive. Duodenal biopsy, rectal biopsy and stool examination could not identify any opportunistic organism.

Percutaneous catheter drainage in pancreatic pseudocysts.

Percutaneous catheter drainage (PCD) was performed in 12 pancreatic pseudocysts in 11 patients. The procedure was performed under realtime ultrasound guidance adopting a direct transperitoneal approach in all cases. Complete cure was achieved in 9 (75%) of the Pseudocysts drained. Success rate was higher in pseudocysts not communicating with the main pancreatic duct (MPD), 7 of 8 (87.5%) as compared to those with ductal communication, 2 of 4 (50%). The mean duration of catheter drainage was 14.2 days in the first group while it was significantly longer, (42.5 days) in the latter group. No death or major complication related to the procedure was encountered in the study. A single pseudocyst got infected after catheter insertion but it was treated successfully with antibiotics. The follow up period was 3-18 months with a mean of 6.8 months. PCD failed in 2 pseudocysts communicating with MPD and associated strictures in the MPD. In one case having no communication with MPD the procedure failed because the cyst had thick debris which could not be drained properly. PCD may be a safe and effective therapy in the management of pseudocysts with best results in those not communicating with the MPD. Communicating pseudocysts, also having strictures in MPD, should not be subjected to PCD.

von Hippel Lindau syndrome presenting as obstructive jaundice with involvement of pancreas in two siblings.

Von Hippel Lindau disease is rare autosomal dominant disorder. In our patient's family, 4 out of 7 siblings had manifestations of the disease; 3 of those affected had pancreatic lesions with obstructive jaundice in 2 siblings caused by pancreatic cysts is reported for the first time.

Percutaneous transluminal balloon angioplasty in suprahepatic IVC obstruction--Budd-Chiari syndrome.

Encouraging results of Transluminal Angioplasty for Budd-Chiari Syndrome due to obstruction of Suprahepatic inferior vena cava have been reported in the last decade. We present our experience with two such patients, treated with balloon dilatation producing dramatic clinical improvements and control of disease on follow-up.

Comparative evaluation of blood schizontocidal activity of quinine and quinidine against drug resistant rodent malaria.

Blood schizontocidal activity of quinine and quinidine has been compared against sensitive as well as chloroquine/mefloquine/quinine resistant strains of Plasmodium berghei and a multiple resistant strain of P. yoelii nigeriensis in Swiss mice. Evaluation of results on ED50/ED90 basis has shown distinct superiority of quinidine over quinine against sensitive as well as drug resistant strain of rodent malaria.

Pattern of relapses in sporozoite induced Plasmodium cynomolgi B infection in rhesus monkeys.

The pattern of sequential relapses in 10 rhesus monkeys following inoculation of sporozoites of Plasmodium cynomolgi B has been studied after administering curative dose of chloroquine (5 mg/kg base X 7 days) to eliminate blood parasitaemia after each relapse. Observation for periods ranging from 109 to 245 days showed that the interval between first six relapses was 19.3 +/- 6.77 days (1st relapse), 20.9 +/- 8.43 days (2nd relapse), 22.8 +/- 8.55 days (3rd relapse), 27.8 +/- 10.0 days (4th relapse), 31.67 +/- 11.50 days (5th relapse) and 32.5 +/- 16.26 days (6th relapse). The results of this study indicate a gradual extension of the relapse interval in successive relapses.

Causal prophylactic activity of a new 8-aminoquinoline derivative against Plasmodium cynomolgi B in rhesus monkeys.

A new 8-aminoquinoline derivative, N1-(3-acetyl-4-5-dihydro-2 furanyl)-N4-(6-methoxy-8-quinolinyl)1,4-pentanediamine, synthesized at CDRI, Lucknow, showed causal prophylactic activity at 3.16 mg/kg x 3 doses (on day -1, 0 and +1) against sporozoite induced P. cynomolgi B infection in rhesus monkeys. Single dose of 10 mg/kg of this compound on day 0 also prevented establishment of patient infection. Activity of the compound was comparable to that of primaquine (with causal prophylactic activity at 1.78 mg/kg in three day test and at 10.0 mg/kg in single dose test).

Effect of a new 8-aminoquinoline antimalarial compound on hepatic microsomal mixed function oxidase system of mice.

A new 8-aminoquinoline derivative (compound 80/53) synthesized at the Central Drug Research Institute, Lucknow (India), has been found to be an active anti-relapse (tissue schizontocidal) compound. Compound 80/53 at 8.75 mg/kg x 4 days and primaquine at 7.00 mg/kg (base) x 4 days given orally to Swiss mice led to inhibition of the different components of the hepatic microsomal mixed function oxidase system to varying degrees. Compound 80/53 inhibited cytochrome P-450, aminopyrine-N-demethylase, aniline and benzo (a) pyrene hydroxylase, cytochrome b5 and heme content of the normal mice by 12, 14, 0, 57, 20 and 6 per cent respectively, whereas the inhibition caused by primaquine in these components was 25, 21, 17, 48, 26 and 6 per cent respectively. Thus, there was less inhibition of hepatic microsomal MFO system of mice by compound 80/53 as compared to that by primaquine.