Molecular Orbital Calculations on Polythiophenes Containing Heterocyclic Substituents: Effect of Structure on Electronic Transitions

Molecular orbital calculations have been performed on thiophene oligomers bearing heterocyclic substituents at the third position in order to understand the interplay of effects such as the nature of substituent, skeletal substitution pattern, heteroatom identity, etc. on electronic transitions. The geometry optimization was carried out using the semiempirical AM1 method, and the electronic transitions predicted for the oligomers were extrapolated for polymers using an oligomeric approach. The experimentally determined optical transitions were found to follow the predicted trend of electronic transitions of monomers and polymers.

p27(SJ), a novel protein in St John's Wort, that suppresses expression of HIV-1 genome

Transcription of the HIV-1 genome is controlled by the cooperation of viral regulatory proteins and several host factors which bind to specific DNA sequences within the viral promoter spanning the long terminal repeat, (LTR). Here, we describe the identification of a novel protein, p27(SJ), present in a laboratory callus culture of Hypericum perforatum (St John's Wort) that suppresses transcription of the HIV-1 genome in several human cell types including primary culture of microglia and astrocytes. p27(SJ) associates with C/EBPbeta, a transcription factor that regulates expression of the HIV-1 genome in macrophages and monocytic cells, and the viral transactivator, Tat. The association of p27(SJ) with C/EBPbeta and Tat alters their subcellular localization, causing their accumulation in the perinuclear cytoplasmic compartment of the cells. Fusion of a nuclear localization signal to p27(SJ) forces its entry into the nucleus and diminishes the capacity of p27(SJ) to suppress Tat activity, but does not alter its ability to suppress C/EBPbeta activation of the LTR. Results from binding assays showed the inhibitory effect of p27(SJ) on C/EBPbeta interaction with DNA. Finally, our results demonstrate that expression of p27(SJ) decreases the level of viral replication in HIV-1-infected cells. These observations suggest the potential for the development of a therapeutic advance based on p27(SJ) protein to control HIV-1 transcription and replication in cells associated with HIV-1 infection in the brain.

Immunomodulation using the recombinant monoclonal human B7-DC cross-linking antibody rHIgM12

A patient with Waldenstrom's macroglobulinaemia expresses a high titre IgM antibody in serum that binds both mouse and human dendritic cells (DC) in a B7-DC (PD-L2)-dependent manner. We have reported previously that purified antibody from patient serum activates immature and mature DC in vitro, enhancing the ability of these professional antigen-presenting cells to activate naive T cells, take up antigen, resist a cytokine-depleted environment and secrete immunomodulatory cytokines, such as interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha. Systemic treatment of experimental animals with this antibody induces potent anti-melanoma immunity and modulates protectively the recall response against antigen challenge through the airway in an experimental model of inflammatory airway disease. Here we describe a monoclonal IgM antibody derived from this serum immunoglobulin that recapitulates each of these earlier observations, providing direct evidence that M protein from the Waldenstrom's patient mediates these potent immunomodulatory effects. Furthermore, cell lines expressing this recombinant form of the human antibody provide the basis for developing this reagent for clinical application.

Brain tissue phantoms for optical near infrared imaging

In this study, solid, stable, and cost-effective optical phantoms of scalp-skull, white matter and grey matter are developed by inverse method. To begin with, to obtain a range of optical parameters, absorption and reduced scattering coefficients (mu(a) and mu(s)', respectively), 20 homogeneous phantoms were made of paraffin wax by using optically contrast black and highly scattering white colouring materials in different combination. By comparing the measured reflectance values for each phantom got from the four channel reflectometer with that obtained from steady-state diffusion equation, the values of mu(a) and mu(s)' were determined. Next, phantoms which exhibit specific optical properties of scalp-skull, white and grey matter are developed iteratively by comparing actual reflectance measurements got by adjusting the colour concentration with the predicted reflectance values from the diffusion equation. This is done as follows: to obtain mu(a) of 0.04 mm(-1) for scalp-skull, 9.5 mg of black dye per 100 ml of wax added since more attenuation of light occurs in bone tissue. To obtain a mu(s)' 6.0 mm(-1) for white matter in brain tissue, 190 mg of white dye per 100 ml of wax was used to facilitate more scatter of light. The colour concentrations of phantoms were then adjusted to obtain the predetermined values of optical parameters for scalp-skull, grey and white matter.

Quantum chemical studies on polythiophenes containing heterocyclic substituents: Effect of structure on the band gap

Color tuning by the tailoring of substituents at the 3-position of thiophene is very encouraging, and comparative experimental and theoretical studies proved to be powerful in the search for a suitable design for the above. Since the novel polythiophene-based materials substituted with five-membered/six-membered ring containing sulphur and nitrogen at different positions are proven to be potential candidates for electron-transporting hole blocking functions, the structure-property relationship of these systems have been focused in the present study. Molecular-orbital calculations are applied to obtain the optimized geometries and band gaps of the thiophene oligomers. An oligomeric approach has been implemented for calculating the band gaps, and the theoretically obtained band gaps for the different model compounds are compared. Density-functional theory B3LYP6-31G* predicted band-gap values are compared with the experimental band gaps obtained from optical-absorption edge. The predicted values show little deviations from experimental band gaps, but the trend in band gap is found to be the same in experimental and theoretical results in most of the cases. Hence, this study illustrates the usefulness of quantum-mechanical calculations in understanding the effects of various structural parameters on optical band gap.

Covered stents deployed for coarctation of aorta with aneurysm

Three patients presented to us with upper extremity hypertension and aortic coarctation. Aortic angiograms and spiral computerized tomography delineated the anatomy at the site of coarctation and the associated small aneurysmal dilation. They were taken up for percutaneous stenting of the coarctation segment with cheathum-platinum covered stents. Post-deployment, there was a significant fall in pullback gradients and exclusion of the aneurysms.

Role of transition zone sampling by TURP in patients with raised PSA and multiple negative transrectal ultrasound-guided prostatic biopsies

The purpose of the study was to determine the role of transurethral resection of the prostate (TURP) to detect prostate cancer in patients with consistently negative transrectal ultrasound-guided biopsies of the prostate. We retrospectively identified and analysed the patients who also had at least two sets of transrectal ultrasound guided sextant prostate biopsies before their TURP during the period between 1998 and 2002. A total of 14 such patients were identified and the outcome of TURP was analysed. Three patients were found to have cancer in the resected specimen (3/14 = 21%). All three cancers were significant (Gleason scores between 6 and 8) and required further treatment. In patients who have rising levels of prostate-specific antigen and who have had multiple negative peripheral zone biopsies, the presence of biologically important transition zone cancers needs to be considered. This can be detected by transurethral resection of the prostate that samples the transition zone of the prostate.

Repeat survey of current practice regarding corticosteroid prophylaxis for patients at increased risk of adverse reaction to intravascular contrast agents

AIM

To compare the findings of a survey undertaken by us in 2002 regarding steroid premedication given in radiology departments to reduce the risk of adverse reactions in patients at increased risk of intravascular contrast media reactions with a similar survey published in 1994 by R. Seymour et al. The high risk patients considered in our survey were patients with history of asthma, drug allergies, hay fever and eczema.

MATERIALS AND METHODS

A total of 225 questionnaires were sent to the consultant in charge for audit for radiology departments from the list given by the Royal College of Radiologists. 175 of the 225 questionnaires were returned (response rate 77.8%) and of these 172 were analysed with respect to the type, dose and duration of steroids.

RESULTS

Compared to the survey in 1994, it was found that the number of departments who use steroid cover for all category of risk factors had increased compared to previous survey (73.8% in 2002 versus 55.3% in 1994 (p=0.001). There is now almost universal use of non-ionic contrast 98.8% versus 82.4% in 1994 (p=0.001). There is no agreed policy among radiology departments for the need or the dose or duration of steroid cover.

CONCLUSION

Despite the more widespread use of non-ionic contrast media, the use of steroid premedication has increased which is contrary to what is expected as the incidence of adverse reaction to non ionic media is less than ionic contrast media.

Three-dimensional stress analysis for the mechanics of plantar ulcers in diabetic neuropathy

In diabetic neuropathic subjects, the hardness of foot sole soft tissue increases, and its thickness reduces, in different foot sole areas. Finite element analysis (FEA) of a three-dimensional two-arch model of the foot was performed to evaluate the effect of foot sole stresses on plantar ulcer development. Three sets of foot sole soft-tissue properties, i.e. isotropic (with control hardness value), diabetic isotropic (with higher hardness value) and anisotropic diabetic conditions, were simulated in the push-off phase, with decreasing foot sole soft-tissue thicknesses in the forefoot region, and the corresponding stresses were calculated. The results of the stress analyses for diabetic subject (anisotropic) foot models showed that, with non-uniformly increased hardness and decreased foot sole soft-tissue thickness, the normal and shear stresses at the foot sole increased (compared with control values) by 52.6% and 53.4%, respectively. Stress analyses also showed high ratios of gradients of normal and shear stresses of the order of 6.6 and 3.3 times the control values on the surface of the foot sole, and high relative values of stress gradients for normal and shear stresses of 6.25 and 4.35 times control values, respectively, between the foot sole surface and the adjacent inner layer of the foot sole, around a particular region of the foot sole with anisotropic properties. These ratios of high gradients and relative gradients of stresses due to changes in soft-tissue properties may be responsible for the development of plantar ulcers in diabetic neuropathic feet.

Gingival fibromatosis and growth hormone deficiency syndrome--report of a rare case and review of literature

Oikarinen et al in 1989 reported a syndrome associated with generalized gingival fibromatosis and growth hormone deficiency. This is a case report of a 15-year-old female patient who presented to the Government Dental College, Chennai with generalized gingival fibromatosis and growth hormone deficiency. Interestingly, the histopathology of the excised gingival overgrowth showed dense collagenous connective tissue in which were strewn calcified structures that resembled cementum. This syndrome is being reported for the second time after its first case report in 1989 by Oikarinen et al. We are herewith reporting this case for its rarity with a brief review of literature of syndromes associated with generalized gingival fibromatosis.

Dextrocardia: an analysis of cardiac structures in 125 patients

BACKGROUND

Dextrocardia is associated with multiple and complex congenital cardiac anomalies. Precise anatomical diagnosis is essential for successful surgery. Spectrum of congenital malformations in cases of dextrocardia is based primarily on two-dimensional echocardiographic studies. The purpose of the current study was to use colour Doppler echocardiography in large number of patients.

METHODS

Patients of dextrocardia were studied retrospectively, by reviewing database of our echocardiographic laboratory over last 10 years. Standard criteria for diagnosis of situs were used. Detailed segmental analysis for cardiac anatomy and associated malformations was done using previously suggested and well accepted terms and definitions. Cardiac anatomy was confirmed on catheterization and during surgery in few cases.

RESULTS

Of total 125 patients, dextrocardia was most common with situs inversus (39.2%) followed by situs solitus (34.4%) and situs ambiguous [26.4% (right isomerism in 18.4% and left isomerism in 8.0%)]. Mean age was 9.2+/-11.2 years (range; 3 days to 60 years), 82 males and 43 females. In situs inversus dextrocardia, majority (73.4%) had concordant atrioventricular (AV) connections while discordant AV connections and univentricular atrioventricular connections (UVAVC) were present in 12.2 and 14.3% patients, respectively. Majority of patients with concordant AV connections (72.2%) also had concordant VA (ventriculo-arterial) connections (conotruncal anomalies were commonest). Similarly, majority of patients with discordant AV connections (66.7%) also had discordant VA connections. Commonly (44.9%), these patients presented with decreased pulmonary blood flow (Qp). Total 28.6% patients had normal intracardiac anatomy (10.2% presented with rheumatic heart disease). In situs solitus dextrocardia, majority (51.2%) had AV concordance while discordant AV connections and UVAVC were present in 41.9 and 7.0% patients, respectively. In patients with concordant AV connections, majority (77.2%) had VA concordance (majority presented with increased Qp due to pre or post-tricuspid shunts). Similarly, majority of patients with discordant AV connections (88.9%) also had discordant VA connections (88.9% presented with decreased Qp). Only 7.0% patients with situs solitus dextrocardia had normal intracardiac anatomy. The striking features of right isomerism were male predominance (male:female ratio 2.2:1), cyanosis with decreased Qp in 86.9%, and high incidence of UVAVC and venous system anomalies (39.1% each). Striking features of left isomerism were biventricular ambiguous AV connections in all except one, presentation with increased Qp in 60.0% and presence of inferior vena caval interruption in 60.0% patients.

CONCLUSIONS

Present study, largest study of dextrocardia till date reconfirms that these patients have variable intracardiac anatomy depending upon their situs and types of segmental connections. These patients can present with different haemodynamic subsets, which can be correctly identified by colour Doppler echocardiography. Diagnostic accuracy and a better understanding of the various types of dextrocardia are essential, since improved surgical techniques have made it possible to correct many of these complex abnormalities.

Natural history and predictors of moderate mitral regurgitation following balloon mitral valvuloplasty using Inoue balloon

BACKGROUND

We studied the predictors and natural history of moderate mitral regurgitation following valvuloplasty using Inoue balloon since it has not been well documented in a large series.

METHODS

Balloon mitral valvuloplasty was performed in 590 consecutive patients with severe mitral stenosis with mitral regurgitation of mild or lesser grade. Echocardiography and haemodynamics of patients who developed moderate mitral regurgitation were compared with those who did not. They were followed-up. Factors that predicted the development of moderate regurgitation were studied.

RESULTS

21 patients (3.5%) developed moderate regurgitation (identified by auscultation, haemodynamics, angiography and colour flow mapping). They were managed conservatively. At 3 months, regurgitation decreased in severity to mild grade in 12 patients. At 1 year, it was trivial in 5, mild in 11 and remained moderate in 5. There was progressive symptomatic improvement. No clinical, echocardiographic, hemodynamic or procedural variables could predict the development of moderate mitral regurgitation.

CONCLUSIONS

Patients with moderate regurgitation after mitral valvuloplasty show gradual improvement in regurgitation and symptoms. There were no factors-clinical, echocardiographic, hemodynamic or procedural-that predicted the occurrence of moderate MR after BMV.

Malignant acanthosis nigricans with occult primary

A case of generalized malignant acanthosis nigricans of 2 years duration is reported. In spite of the long duration of this cutaneous marker of internal malignancy, the patient was completely asymptomatic and extensive investigations revealed the presence of widespread metastasis of mucin secreting signet cell adenocarcinoma from an unknown primary site. In addition the patient also had acquired hypertrichosis lanuginose and florid cutaneous papillomatosis which are also markers of internal malignancy.

Predictive accuracy of commissural morphology and its role in determining the outcome following Inoue balloon mitral valvotomy

BACKGROUND

Commissural morphology is an important predictor of outcome following balloon mitral valvotomy. The aim of this prospective study was to assess if the site of commissural splitting could be reliably predicted by echocardiography and whether the extent of commissural split affected the result of balloon mitral valvotomy.

METHODS AND RESULTS

A total of 140 patients (mean age 29.1+/-8.6 years) were studied. Prediction of splitting was done based on the presence of echolucent dark zones as seen in the parasternal short-axis view on echocardiography. Of 102 patients in whom a split of both commissures was predicted, the prediction was accurate in 86% (88/102). Of 33 patients with a predicted unilateral split, the accuracy of prediction was 82% (27/33). In the 5 patients with bilateral commissural fibrosis (in whom none of the commissures were predicted to split), all had a unilateral split. Overall, 93 patients (66%) had a bilateral commissural split, 43 (31%) had a unilateral split, and 4 had no commissural split. All the latter 4 developed moderate-to-severe mitral regurgitation. Those with bilateral commissural split following balloon mitral valvotomy had lower transmitral gradients (5.53+/-1.46 v 7.4+/-1.2 3 mmHg, p = 0.03) and greater mitral valve area (1.83+/-0.15 v. 1.64+/-0.15 cm2, p<0.02), as compared to those with unicommissural split. The incidence of an increase in mitral regurgitation by > or = grade 1 was also lower in the former group (7.5% v. 28%). An optimal result with the first dilatation (using a balloon size <2 mm of the predicted size) was achieved more frequently in those with a bilateral split (18% vs 8%). Oversizing of the balloon by 2 mm (of the predicted size) was done more frequently (19% v. 7%) in those with unicommissural split.

CONCLUSIONS

We conclude that the assessment of commissural morphology is possible with excellent predictive accuracy. In this study, those with bilateral commissural split had more favorable hemodynamic results with lower transmitral gradients. greater mitral valve area and lesser frequency of mitral regurgitation in contrast to those with unicommissural split.

Concurrent percutaneous atrial septal defect closure and pulmonary valvuloplasty

Severe pulmonary valve stenosis in association with a large atrial septal defect is uncommon. Simultaneous percutaneous closure of the atrial septal defect and pulmonary valvuloplasty appears to be an attractive modality when compared to patients with these two lesions being subjected to surgery or being treated percutaneously at different sittings. We encountered two cases, both with significant pulmonary valvular stenosis associated with atrial septal defect (fossa ovalis type). Both lesions were successfully treated percutaneously in the same sitting. Pulmonary valvuloplasty was done initially and the atrial septal defect closed later to minimize catheter manipulation after device implantation.

Severe thrombocytopenia possibly related to readministration of eptifibatide

Thrombocytopenia following eptifibatide therapy is a rare event, and acute severe thrombocytopenia following readministration has not been reported. We describe a case of acute severe thrombocytopenia following reexposure to eptifibatide during percutaneous coronary intervention. We continue to monitor platelet counts at 2-4 hr and 16-24 hr following administration of any glycoprotein IIb/IIIa inhibitor. Cathet Cardiovasc Intervent 2001;54:63-67.

Real-time optical coherence tomography of the anterior segment at 1310 nm

BACKGROUND

Recent advances in high-speed scanning technology have enabled a new generation of optical coherence tomographic (OCT) systems to perform imaging at video rate. Here, a handheld OCT probe capable of imaging the anterior segment of the eye at high frame rates is demonstrated for the first time.

OBJECTIVE

To demonstrate real-time OCT imaging of anterior segment structures.

DESIGN

Survey of anterior segment structures in normal human subjects.

SETTING

Laboratory.

MAIN OUTCOME MEASURES

Achieving real-time imaging of the anterior segment, satisfactory image quality, and convenience of a handheld probe.

RESULTS

Optical coherence tomographic imaging of the anterior segment of the eyes of human subjects was performed using 1310-nm wavelength light with an image rate of 8 frames per second. Imaging trials demonstrated clear resolution of corneal epithelium and stroma, sclerocorneal junction, sclera, iris pigment epithelium and stroma, and anterior lens capsule. The anterior chamber angle was clearly visualized. Limited imaging of the ciliary body was performed. Real-time imaging of pupillary constriction in response to light stimulus was also performed.

CONCLUSION

High-speed OCT at 1310-nm wavelength is a potentially useful technique for noninvasive assessment of anterior segment structures.

CLINICAL RELEVANCE

Our results suggest that real-time OCT has potential applications in glaucoma evaluation and refractive surgery.

Left atrial and pulmonary artery wedge pressure monitoring during balloon mitral valvuloplasty

OBJECTIVE

We tested the accuracy of pulmonary artery wedge (PAW) pressure as a guide to the degree of pulmonary venous hypertension.

METHODS

Left atrial (LA) pressure and PAW pressure were analysed before and after balloon mitral valvuloplasty (BMV) in patients with rheumatic mitral stenosis.

RESULTS

Correlations between LA and PAW pressures for a wave, v wave and mean pressure were excellent before BMV (r=0.96, r=0.97 and r=0.99 respectively) and after BMV (r=0.98, r=0.98 and r=1.00 respectively). The fall in mean LA pressure (11.3 +/- 7.9 mm Hg) and in mean PAW pressure (11.1 +/- 7.9 mm Hg) also correlated well. Correlation was good both before and after BMV when subgrouping was done based on average pulmonary vascular resistance and average LA mean pressure in each group.

CONCLUSIONS

There is good correlation of PAW pressure with LA pressure even in the presence of pulmonary arterial or venous hypertension. It can replace LA pressure monitoring in any clinical setting.

Infrequent occurrence of silent HBV infection among Indian patients with chronic liver disease

OBJECTIVE

To investigate the occurrence of silent hepatitis B virus (HBV) infection among patients with chronic liver disease (CLD).

METHODS

Plasma samples from 71 CLD patients including 9 HBsAg-positive individuals were tested for HBV DNA by nested polymerase chain reaction (nPCR), and for HBV serum markers, i.e., anti-HBc antibody, HBeAg and anti-HBe antibody. The individuals were also tested for hepatitis C virus (HCV) RNA and anti-HCV antibody.

RESULTS

Among 62 HBsAg-negative patients, silent HBV infection was seen in only two (3.2%). Silent HBV infection was not found in any of the 26 patients who had evidence of HCV infection. One HBsAg-positive patient was positive for anti-HCV in the absence of HCV RNA.

CONCLUSIONS

There is a low rate of silent HBV infection among patients with CLD in India, where HBV is moderately endemic. Silent HBV infection is not associated with HCV-related CLD, which is in contrast to reports from other HBV-endemic areas in Asia.

Acquisition and analysis of brainstem auditory evoked responses of normal and diseased subjects by spectral estimation

Human brainstem auditory evoked responses (BAERs) are sensory evoked potentials that can be recorded within a few milliseconds following a transient acoustic stimulus (click signal). This paper suggests a novel technique to clearly demarcate normals and patients with complaints of vertigo and deafness by computing hitherto unused power spectral parameters from the BAER signals recorded on them. The BAER spectrum of normal subjects contains three main frequency components, i.e. low-, mid- and high-frequency components around 100, 500 and 1000 Hz, respectively, which is not so in the case of diseased subjects. The spectral parameters, i.e. the mean power frequency, median frequency, the ratios of the integrated power at dominant frequencies to that of the total power in spectrum and change in spectral power (CP) between these dominant frequency components are used to classify the recorded BAER signals into those of normals and the patients, and aid the clinician in quick and better diagnosis. The ranges of CP are estimated for the different groups and appear to be the most dominant parameter in the classification of the BAER signals.

Non-surgical closure of large ductus arteriosus using Amplatzer Duct Occluder feasibility and early follow-up results

The aim of the study was the assess feasibility of closing large patent arterial ducts (PDA) in infants and children using the new Amplatzer Duct Occluder. All patients diagnosed to be having PDA were considered as potential candidates to undergo the device closure. 19 patients were diagnosed to be having PDA larger than 4 mm. There were 10 males and 9 females, their age ranged from 6 months to 120 months with a mean of 45 months. Mean body weight was 14.5 kg with a range from 7 kg to 23 kg. The procedure was carried out under Ketamine sedation and local anesthesia. The device was implanted by the transvenous route in all. Mean PDA diameter was 5 mm (range 4 mm-6.7 mm). Complete closure was achieved in 16/18 (88%) within 24 hours of the procedure. All patient have been followed for 3 months, and have documented complete closure, there is no evidence of aortic or left pulmonary stenosis in any of our patients. The unsuccessful attempt was in a malnourished patient (weighing 4.7 kg) with an arterial duct measuring 6.7 mm on angiography. This duct was considered too big for device closure and the procedure was abandoned. This patient subsequently has undergone successful surgical ligation. Catheter closure of large PDA in small children is feasible, safe and efficacious. However, it may still not be possible to close large PDA in very small or underweight children, for the fear of causing obstruction to the descending aorta. Further long-term is follow-up required to show sustained benefits without any side effects.

Transcatheter closure of patent ductus arteriosus

OBJECTIVE

To present short and intermediate results of catheter closure of patent ductus artereiosus using spring coils and Amplatzer duct occluder.

SETTING

Tertiary care referral hospital in New Delhi.

METHOD

121 patients were diagnosed to be having patency of the arterial duct between October 1996 and December 1999. Their ages ranged between 4 mo and 480 mo (mean 80.5 mo). Before August 1998 only spring coils were used as an alternative to surgical closure of the duct, whereas between August 1998 and December 1999 both coils and device were used.

RESULTS

Spring coils were attempted in 48, Amplatzer duct occluder in 44 and 29 patients were referred for surgery. Coils were successfully deployed in 42/48 (87.5%) and device in 42/44 (95.5%) patients. Complete closure of the arterial duct was seen in 96% patients in the coil closure group at the end of one year and 100% closure was achieved in the device closure group at the end of 3 months in all the patients followed. Coil embolised in 11 patients, significant stenosis of left pulmonary occurred in one patient and severe hemolysis requiring blood transfusion occurred in one patient after coil closure. Six patients required a second procedure to close the residual shunt within 6 months of the initial coil deployment. One patient had loss of femoral artery pulses in right leg after device closure and required heparin infusion for 48 hours. There were 8 failed attempts. All these patients have been operated successfully.

CONCLUSION

Percutaneous closure of the patent ductus arteriosus using Coils or the Amplatzer device is an acceptable method. Small residual shunts are common after the initial procedure especially after coil deployment but most close spontaneously.

Non surgical closure of atrial septal defect using the Amplatzer septal occluder in children--feasibility and early results

OBJECTIVE

To assess the feasibility and early results of Amplatzer septal occluder in children withy secundim atrial septal defect.

SETTING

Tertiary care referral hospital in New Delhi.

METHODS

Forty nine children under 12 years of age were diagnosed to be having fossa ovalis atrial septal defect. Forty nine patients underwent detailed 2D-Echocardiography and color Doppler interrogation for the possibility of non-surgical closure of ASD. Sixteen children between age 2.5-12 years (mean 6.5 years) were enrolled into the study. Their weight ranged from 10 kg to 42 kg and there were 9 males and 7 females. The remaining 33 were not considered suitable for device closure in echocardiography and were referred for surgery.

RESULTS

All patients had more than 1.8 : 1 shunt. The device was successfully deployed in 13/16 patients. ASD stretched diameter ranged between 13 mm-30 mm (mean 15 mm) and the device size ranged between 14 mm-22 mm. One patient had fenestrated ASD, in this patient the largest of the defect was crossed and closed with 24 mm device resulting in closure of all three defects. We failed in three of our attempts, on one there were deficient inferior margins while in the other two cases the ASD stretched size was such that the device would have encroached upon adjacent structures, hence the procedure was abandoned. All these patients have been operated successfully. Complete abolition of shunt was seen in 38% patients in the immediate post deployment period. At 24 hours complete closure was seen in 12/13 (92%) patients while one patient had trivial residual shunting across the device. This patient also achieved complete closure of atrial shunting when evaluated at three months follow-up.

CONCLUSION

Device closure of ASD is emerging as an alternative to surgical closure. However, with the currently available device only a limited number of atrial septal defects can be closed. Long-term studies are required to show sustained benefits and absence of side effects of this device.

Prevalence of enterically transmitted hepatitis viruses in patients attending a tertiary--care hospital in south India

The prevalance of enterically transmitted hepatitis viruses, namely, hepatitis A virus (HAV) and hepatitis E virus (HEV) were studied in 404 patients with acute hepatitis attending a tertiary-care hospital in south India. Presence of current HAV/HEV infection was ascertained by the demonstration of IgM antibodies. In 381 patients tested for both agents, HAV IgM was present in 51(13.3%) and HEV IgM present in 66(17.3%). There was dual infection in 3 males (0.8%). HEV infection was seen mostly in older children and adults with only 5.5% occurring in children < 12 years of age. HAV infection was commonly seen to occur in < 12 years of age group (52.7%). One hundred and twenty-six patients were from the Vellore region, among whom HAV and/or HEV aetiology was observed in 28.5%. In this region there did not appear to be any correlation between occurrence of acute hepatitis due to these viruses and rainfall or environmental temperature. Acute hepatitis due to enteric hepatitis viruses was seen throughout the year.

Role of molecular techniques in the detection of HBV DNA & HCV RNA among renal transplant recipients in India

In this study we have investigated the occurrence of hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV) infections among 68 renal transplant recipients. Replicative HBV and replicative HCV infections were seen in 12 (17.6%) and 38 (55.9%) patients respectively, the difference was statistically significant (P < 0.001). Among the 38 HCV RNA+ individuals, anti-HCV was present only in 23. Anti-HCV in the absence of HCV RNA was detected in one patient. Anti-HDV antibody was seen in 2 (15.4%) of the 13 HBV infected individuals. Nine (13.2%) of the 68 individuals had replicative dual infection with HBV and HCV. Triple infection (HBV DNA+, HCV RNA+, anti-HDV+) was seen in 2 transplant recipients. There was significantly higher demonstration of replicative HCV (P < 0.001) in transplant recipients having elevated liver enzymes (n = 34) as compared to transplant recipients having normal liver enzyme levels (n = 34). Though not significant, a higher detection rate was also seen with replicative HBV infection and replicative dual infection among transplant recipients with elevated liver enzymes. The higher detection of HCV in renal transplant recipients by molecular techniques, emphasizes the need for HCV RNA testing. Further deliberate attempts to change practices to reduce this problem may also improve graft and patient survival in recipients.