Effects of cholesterol and enantiomeric cholesterol on P-glycoprotein localization and function in low-density membrane domains

Multidrug resistance P-glycoprotein (Pgp) has been reported to localize in low-density, cholesterol-enriched membranes. However, effects of low-density membrane domains on function of Pgp remain unexplored in whole cell systems. In cells that express modest levels of the protein endogenously or through drug selection, Pgp predominantly localized to low-density membranes following separation on a sucrose gradient. When highly overexpressed in NIH 3T3 cells, a prominent amount of Pgp also was detected in high-density membranes. Removing cholesterol from cells with beta-methylcyclodextrin (CD), a sterol acceptor molecule, shifted fractions that contained Pgp from low toward high density, and this effect was reversed to a similar extent by restoring sterols with either cholesterol or enantiomeric cholesterol. However, function of human MDR1 Pgp as probed with Tc-Sestamibi, a transport substrate for Pgp, was not dependent on localization of Pgp in cholesterol-enriched membranes. Specific inhibition of MDR1 Pgp with GF120918 or LY335979 also was independent of cholesterol. Cell-type-specific effects of cholesterol content on function of human Pgp were detected by use of daunomycin, another substrate for Pgp, although efficacy of inhibitors remained independent of cholesterol. Conversely, both function and inhibition of hamster Pgp as measured with Tc-Sestamibi and daunomycin were in part dependent on normal cell content of cholesterol. These data show that Pgp preferentially localizes to low-density, cholesterol-enriched membrane domains, but acute depletion of cholesterol impacts Pgp-mediated drug transport in a substrate- and cell-type-specific manner.

Surgical experience with intracardiac myxomas: long-term follow-up

BACKGROUND

Myxomas are the most common benign intracardiac tumors. This report summarizes our 20-year experience with these tumors.

METHODS

Sixty-six patients (25 male) with a median age of 39 years (range, 6 to 70 years) underwent surgical excision of primary or recurrent intracardiac myxomas during the years 1976 to 1996. Symptom duration ranged from 2 to 8 months. There were 55 left atrial myxomas, 10 right atrial myxomas, and 1 biatrial myxoma. Three of the patients were in one family. The surgical approach comprised complete wide excision.

RESULTS

There were two early deaths. Late follow-up is 89% (57/64) complete. There was one late death, which was not due to a cardiac cause. Echocardiography at a mean follow-up of 66.9 months (range, 7 to 241 months) showed no recurrence of sporadic myxomas. However, 2 of the 3 patients with familial myxomas had recurrence.

CONCLUSIONS

Surgical excision of atrial myxoma gives excellent short-term and long-term results leading to eventual cure of nonfamilial myxomas. However, familial myxomas retain a strong tendency to recur even 20 years after excision.

The nonfeminizing enantiomer of 17beta-estradiol exerts protective effects in neuronal cultures and a rat model of cerebral ischemia

Estrogens are potent neuroprotective compounds in a variety of animal and cell culture models, and data indicate that estrogen receptor (ER)-mediated gene transcription is not required for some of these effects. To further address the requirement for an ER in estrogen enhancement of neuronal survival, we assessed the enantiomer of 17beta-estradiol (ENT-E(2)), which has identical chemical properties but interacts only weakly with known ERs, for neuroprotective efficacy. ENT-E(2) was both as potent and efficacious as 17beta-estradiol in attenuating oxidative stress-induced death in HT-22 cells, a murine hippocampal cell line. Further, ENT-E(2) completely attenuated H(2)O(2) toxicity in human SK-N-SH neuroblastoma cells at a 10 nM concentration. In a rodent model of focal ischemia, 17beta-estradiol (100 microgram/kg) or ENT-E(2) (100 microgram/kg), injected 2 h before middle cerebral artery occlusion, resulted in a 60 and 61% reduction in lesion volume, respectively. ENT-E(2), at the doses effective in this study, did not stimulate uterine growth or vaginal opening in juvenile female rats when administered daily for 3 days. These data indicate that the neuroprotective effects of estrogens, both in vitro and in vivo, can be disassociated from the peripheral estrogenic actions.

Sinus of Valsalva aneurysms: 20 years' experience

BACKGROUND

Aneurysms of sinus of Valsalva are rare. Here, we analyze retrospectively patients operated on at our center during the last 20 years.

PATIENTS AND METHODS

One hundred four cases of congential aneurysm of sinus of Valsalva were operated upon between January 1977 and April 1996. Only 12 aneurysms were unruptured. The majority (76.9%) arose from the right coronary sinus. The right ventricle was the most common chamber of rupture (58.6%). Ventricular septal defect was associated in 46 patients (44.2%), of which 28 (60.9%) were supracristal. Ventricular septal defect was more common in aneurysms arising from the right coronary sinus (91.3%). Aortic incompetence was found in 45 patients (43.3%). The defect was closed through the aortic root alone in 24 patients (23.1%) and through both the aortic root and the chamber of rupture in the remaining 80 patients. Six patients underwent aortic valve repair, and 21 an aortic valve replacement.

RESULTS

There were two hospital deaths (1.92%). Morbidities were few. Follow-up ranged from 1 to 20 years (mean 8.2 +/- 1.1). There was one late noncardiac death, and in the majority, the long-term follow-up was uneventful.

CONCLUSION

Surgery for aneurysm of sinus of Valsalva yields gratifying results, and it should be undertaken as soon as the condition is diagnosed.

Enantiospecificity of cholesterol function in vivo

The importance of the absolute configuration of cholesterol for its function in vivo is unknown. To directly test this question in vivo, we synthesized the enantiomer of cholesterol (ent-cholesterol) and tested its ability to substitute for natural cholesterol (nat-cholesterol) in the growth, viability, and behavior of Caenorhabditis elegans, a cholesterol auxotroph. First-generation animals grown on ent-cholesterol were viable with only mild behavioral defects. However, ent-cholesterol produced 100% lethality/arrest of their second generation progeny. Isotopically labeled ent-cholesterol incorporated into animals, indicating that its lethality was not secondary to cholesterol starvation. When mixed with nat-cholesterol, ent-cholesterol was not inert; rather, it antagonized the activity of nat-cholesterol. These results demonstrate for the first time that the absolute configuration of cholesterol, not just its physical properties, is essential for its functions in vivo.

Analysis of mutations in the pore-forming region essential for insecticidal activity of a Bacillus thuringiensis delta-endotoxin

The Bacillus thuringiensis insecticidal delta-endotoxins have a three-domain structure, with the seven amphipathic helices which comprise domain I being essential for toxicity. To better define the function of these helices in membrane insertion and toxicity, either site-directed or random mutagenesis of two regions was performed. Thirty-nucleotide segments in the B. thuringiensis cry1Ac1 gene, encoding parts of helix alpha4 and the loop connecting helices alpha4 and alpha5, were randomly mutagenized. This hydrophobic region of the toxin probably inserts into the membrane as a hairpin. Site-directed mutations were also created in specific surface residues of helix alpha3 in order to increase its hydrophobicity. Among 12 random mutations in helix alpha4, 5 resulted in the total loss of toxicity for Manduca sexta and Heliothis virescens, another caused a significant increase in toxicity, and one resulted in decreased toxicity. None of the nontoxic mutants was altered in toxin stability, binding of toxin to a membrane protein, or the ability of the toxin to aggregate in the membrane. Mutations in the loop connecting helices alpha4 and alpha5 did not affect toxicity, nor did mutations in alpha3, which should have enhanced the hydrophobic properties of this helix. In contrast to mutations in helix alpha5, those in helix alpha4 which inactivated the toxin did not affect its capacity to oligomerize in the membrane. Despite the formation of oligomers, there was no ion flow as measured by light scattering. Helix alpha5 is important for oligomerization and perhaps has other functions, whereas helix alpha4 must have a more direct role in establishing the properties of the channel.

Phorbol ester down-regulation of lung surfactant protein B gene expression by cytoplasmic trapping of thyroid transcription factor-1 and hepatocyte nuclear factor 3

The lung-specific surfactant protein B (SP-B) is essential for surfactant function and normal respiration. We investigated the role of thyroid transcription factor-1 (TTF-1) and hepatocyte nuclear factor 3 (HNF3) in the down-regulation of SP-B gene expression by phorbol ester in pulmonary adenocarcinoma H441 cells. Responsiveness to 12-O-tetradecanoylphorbol-13-acetate (TPA) localized to the SP-B proximal promoter (-140/-65 bp) and specifically to binding sites for TTF-1 and HNF3, which act as cell-specific enhancers of SP-B expression. Treatment of cells with TPA (10 nM) caused a time-dependent decrease in both TTF-1 and HNF3 in nuclear extracts and accumulation of both factors in the cytoplasm as assessed by electromobility shift, Western, Southwestern, and immunofluorescence assays. Treatment did not alter the mRNA content or DNA binding activity for either transcription factor. We conclude that down-regulation of SP-B gene expression by phorbol ester involves cytoplasmic trapping and loss of TTF-1 and HNF3 from the nucleus. This mechanism of action is independent of AP-1 and other transcription factors known to be influenced by phorbol ester.

A dual electrochemical sensor for nitrite and nitric oxide

Nafion/lead-ruthenate pyrochlore chemically modified electrode (NPyCME) showed a remarkable dual sensing activity toward NO2- oxidation and NO reduction as demonstrated by cyclic voltammetry (CV), ac-impedance spectroscopy and flow injection analysis (FIA). The mechanistic parameters of current function, charge transfer resistance and exchange current for the NPyCME, GCE and Nafion-coated GCE were evaluated and compared. The disproportionation reaction of NIIIO2- into NIVO3- + NIIO in acidic solution was used as a model system for testing the dual sensing ability of the NPyCME. The obtained crossover peak response for NO2- oxidation and NO reduction in pH 1.65 buffer solution gave the direct proof for the applicability of the NPyCME in the dual electrocatalytic action. By flow injection analysis, under optimized conditions, the calibration curve was linear in the range of 100 nM-100 microM and 800 nM-63.3 microM and the detection limit (S/N = 3) was 4.8 nM and 15.6 nM for NO2- and NO, respectively.

Homograft mitral valve replacement: five years' results

OBJECTIVE

Results of mitral valve replacement with a mitral homograft were evaluated at 5 years to assess the suitability of the procedure.

METHODS

Thirty-seven patients (25 male subjects) aged 10 to 49 years (mean, 32 +/- 10 years) with rheumatic mitral valve disease underwent total (n = 35) or partial (n = 2) mitral valve replacement with a fresh antibiotic-preserved (n = 23) or cryopreserved (n = 14) mitral homograft. The predominant lesion was mitral stenosis (n = 30).

RESULTS

There were 5 early deaths. Operative survivors were followed up for 1 to 60 months (mean, 26.6 +/- 12 months). Among these, 21 patients had severe mitral regurgitation during the follow-up period; 3 died and 8 underwent reoperation. The homograft failure rate was not affected by preoperative physiologic lesion (stenosis vs regurgitation, P =.4), type of homograft (antibiotic-preserved vs cryopreserved homograft, P =.9), papillary muscle pretreatment (yes vs no, P =.9), or addition of posterior collar annuloplasty (yes vs no, P =.2). Among the remaining patients, 5 had moderate mitral regurgitation, 4 had either trivial or mild mitral regurgitation, and 2 were lost to follow-up. Study of the explanted mitral homografts (n = 8) revealed that disruption of one of the donor papillary muscles was responsible for early failures (n = 2), whereas cuspal and chordal degeneration was responsible for late failures (n = 6). Microscopically, the explanted valve lacked any viable cellular elements, and there was no evidence of immunologic injury to the homografts.

CONCLUSION

The mitral homograft did not fulfill our expectations as a suitable substitute for the diseased mitral valve.

Transanal endoscopic microsurgery for rectal carcinoids: the largest reported United States experience

AIM

Rectal carcinoids are often inadequately resected by snare excision during colonoscopy. Transanal endoscopic microsurgery is a minimally invasive procedure with low morbidity that offers full-thickness excision with a low rate of negative margins. It presents an excellent alternative to radical surgery for mid and proximally located lesions. We report the largest United States (US) experience in the use of transanal endoscopic microsurgery for rectal carcinoids.

METHOD

Data of patients who had undergone transanal endoscopic microsurgery for rectal carcinoids were prospectively collected and retrospectively analyzed. Patient and tumour characteristics, operative and perioperative details, as well as oncological outcomes were reviewed.

RESULTS

Over a 12-year period, 24 patients underwent transanal endoscopic microsurgery for rectal carcinoids. Of these, six (25%) were primary surgical resections and 18 (75%) were performed after incomplete snare excisions during colonoscopy. Three (17%) patients who underwent full-thickness resection after snare excision had residual tumour on histopathological examination. Negative margins were obtained in all cases. No recurrences were noted.

CONCLUSION

Transanal endoscopic microsurgery is effective and safe for the surgical resection of rectal carcinoids<2 cm in diameter, with typical features and located more than 5 cm from the anal verge. Transanal endoscopic microsurgery can be used for primary resection or for resection after incomplete colonoscopic snare excision.

Aneurysm of sinus of Valsalva dissecting into interventricular septum

BACKGROUND

Dissection of interventricular septum by aneurysm of the sinus of Valsalva is extremely rare. We present our experience with the management of 10 patients with this condition.

METHODS

Ten patients with aneurysm of the sinus of Valsalva dissecting into the interventricular septum were managed at All India Institute of Medical Sciences, New Delhi, between May 1987 and September 1996. Conduction abnormalities and aortic insufficiency dominated the clinical picture. Eight patients underwent surgical repair. Two patients refused operation, and only permanent pacemaker implantation was done for complete heart block in both these patients.

RESULTS

There was no hospital mortality. Follow-up ranged from 1 to 9 years. There was one late death due to carcinoma of the larynx, and 1 patient required reoperation for persistent aortic insufficiency. All other patients who underwent operation are in New York Heart Association functional class I.

CONCLUSIONS

We recommend surgical repair of this condition to deal with aortic regurgitation and to avoid the potential risk of rupture, thromboembolism, and infective endocarditis. However, surgical repair offers no guarantee against arrhythmias and conduction abnormalities.

Transforming growth factor-beta(1) regulation of surfactant protein B gene expression is mediated by protein kinase-dependent intracellular translocation of thyroid transcription factor-1 and hepatocyte nuclear factor 3

The transforming growth factor-beta (TGF beta) polypeptides control a variety of cellular processes including organogenesis and cellular proliferation and differentiation. In the developing lung, TGF beta(1) treatment inhibits airway branching and expression of the genes for surfactant proteins (SP). Many effects of TGF beta are mediated at the level of gene transcription but there is limited information regarding signaling pathways and target transcription factors. In this study with human pulmonary adenocarcinoma H441 cells, we investigated TGF beta(1) effects on SP-B, a protein which is essential for normal function of pulmonary surfactant. TGF beta(1) (10 ng/ml) reduced SP-B mRNA content in a time-dependent fashion, and transient transfection studies localized responsiveness to the region of the SP-B promoter (-112/-72 bp) containing binding sites for thyroid transcription factor-1 (TTF-1) and hepatocyte nuclear factor 3 (HNF3), transcription factors that are important enhancers of SP gene expression. Using electrophoretic mobility shift assay and immunofluorescence, we demonstrated rapid accumulation of these transcription factors in the cytoplasm and subsequent loss from the nucleus on TGF beta(1) treatment of both adenocarcinoma cells and cultured human fetal lung. TGF beta(1) treatment caused intracellular translocation of protein kinase C and effects of TGF beta(1) were mostly abrogated in the presence of the protein kinase inhibitor calphostin C. We conclude that TGF beta(1), acting via protein phosphorylation, blocks nuclear translocation of TTF-1 and HNF3 which results in down-regulation of the SP-B gene and presumably other pulmonary genes which are transactivated by these factors.

Pulmonary autograft: should it be used in young patients with rheumatic disease?

BACKGROUND

Although pulmonary autograft is being increasingly used to replace the diseased aortic valve with excellent long-term results, its use in the population with rheumatic disease still needs careful evaluation.

PATIENTS AND METHODS

From October 1993 through March 1998, 102 patients underwent aortic valve replacement with a pulmonary autograft (Ross procedure). The mean age was 27.9 +/- 4.2 years (range, 0.8-56 years). The cause was rheumatic disease in 75 patients (73%), bicuspid aortic valve in 26 patients (26%), and myxomatous aortoarteritis in 1 patient (1%). The root replacement technique was used in all. In addition, 31 patients had 33 associated procedures: mitral valve repair (n = 15 patients), open mitral commissurotomy (n = 15 patients), tricuspid repair (n = 2 patients), and homograft mitral valve replacement (n = 1 patient).

RESULTS

Operative mortality was 6.9% (7 patients). Late mortality was 7.8% (8 patients). Follow-up ranged from 1 to 60 months (mean, 25.3 +/- 15.4 months) and was 98% complete. Two patients required reoperation for failed mitral valve repair, and 2 other patients underwent reoperation for failure of both the autograft and mitral valve repair. Echocardiographic assessment showed moderate to severe aortic regurgitation in 13 patients, along with thickening of the autograft. All of these patients had rheumatic disease and were young (<30 years). Ten of these patients had undergone associated mitral valve procedure. Morphologic and histopathologic examination of explanted autografts showed features compatible with rheumatic valvulitis.

CONCLUSION

Pulmonary autograft is susceptible to rheumatic involvement. Young age (<30 years) and associated mitral valve disease are significant risk factors for autograft failure in patients with rheumatic disease. Use of pulmonary autograft in this subgroup of patients requires a cautious approach.

A mimicking enzyme analogue for chemical sensors

An artificial enzyme analogue of Nafion/lead-ruthenium oxide pyrochlore (Py) chemically modified electrode (NPyCME) is synthesized by in situ precipitation through blocking of Nafion's hydrophilic zones. The catalytically active Py sites covered with a hydrophobic core of Nafion resemble an enzymatic structure. Moreover, the NPyCME obeys the Michaelis-Menten mechanism for the oxidation of many organic and biological molecules. This Account highlights aspects of the preparation, characterization, and application of the NPyCME.

Cutaneous manifestations in patients suspected of chikungunya disease

Context:

An epidemic of chikungunya disease occurred in India during late 2005 through 2006 affecting nearly 1,400,000 people.

Aim:

To study the cutaneous manifestations in suspected cases of chikungunya disease.

Settings and Design:

Patients who attended our outpatient departments from January 2006 to September 2006 were prospectively included if they had symptoms of chikungunya disease according to the ‘case definition’ of the National Institute of Communicable Diseases, Directorate General of Health Services, Government of India. The criteria were an acute illness characterized by the sudden onset of fever and several symptoms such as joint pain, headache, backache, photophobia, and eruption during an epidemic of chikungunya fever in the absence of confirmatory serological tests.

Materials and Methods:

A total of 115 patients (65 men and 50 women) who satisfied the above criteria were enrolled for the study.

Results:

An erythematous maculopapular rash subsiding without any sequelae in 3-4 days was the most common cutaneous finding in our patients. Genital ulcers distributed predominantly over the scrotum and base of the penile shaft in men and labia majora in women were the second most common manifestation. Other manifestations included tenderness/edema of hands and feet, grouped hyperpigmented macules over the nose and cheeks, fixed drug eruptions, erythema nodosum, erythema multiformae, generalized urticarial eruptions, and flare up of pre-existing psoriasis and lichen planus.

Conclusions:

To conclude, a plethora of cutaneous manifestations were noted in suspected cases of chikungunya disease. Genital ulcers, to the best of our knowledge, have not been reported during the earlier epidemics but have been reported by others during the present one.

Fixed drug eruptions on male genitalia: clinical and etiologic study

Fixed drug eruptions exclusively involving the genitalia of 60 male patients were investigated. Forty-two of the 60 patients completed tests designed to identify the causative drug. Tetracycline, aspirin, metamizole, and trimethoprim-sulfamethoxazole were found to be common etiologic agents. The sites affected were the glans penis, coronal sulcus, and preputial skin. Superficial ulceration or pigmented areas surrounded by an erythematous halo were the main clinical findings at the time of presentation.

Results of mitral valve reconstruction in children with rheumatic heart disease

BACKGROUND

Between January 1988 and November 1994, we developed techniques of reconstructing diseased mitral valves in patients with rheumatic heart disease. Four hundred thirteen patients underwent mitral valve repair using these techniques. Of these, 125 children and adolescents less than 15 years of age form the study group.

METHODS

The mean age was 8.9 +/- 4.3 years (range, 5 to 15 years). One hundred seventeen patients (93.6%) had rheumatic heart disease. There were 72 boys (57.6%) and 53 girls (42.4%). All of these patients were symptomatic: New York Heart Association class III or IV. Mitral regurgitation alone was present in 49 patients (39.2%), and combined mitral stenosis and regurgitation were present in 76 patients (60.8%). Surgical techniques included commissurotomy (n = 70; 56%), annuloplasty (n = 122; 97.6%), chordal shortening (n = 46; 36.8%), cusp thinning (n = 27; 5.6%), and associated procedures for tricuspid valve disease (6 patients) and aortic valve disease (2 patients).

RESULTS

The operative mortality rate was 4.8% (6 patients), and late deaths occurred in 1.6% (2 patients). Follow-up was 378.25 patient-years. In 15 patients, severe mitral regurgitation developed after a mean follow-up of 37.14 +/- 20.47 months (seven reoperations). At 6 years, actuarial and event-free survival rates were 92.1% +/- 3.19% and 75% +/- 8.18%, respectively. One patient (0.15%/patient-year) had transient right hemiparesis. None had anticoagulation-related bleeding.

CONCLUSION

Mitral valve reconstruction in children and adolescents with rheumatic mitral regurgitation provides satisfactory early results. Progression of disease is the most important risk factor for reoperation. The technique described provided stable repair in the majority of patients.

Immunohistochemical characterisation of Aschoff nodules and endomyocardial inflammatory infiltrates in left atrial appendages from patients with chronic rheumatic heart disease

Fifty left atrial appendages collected fresh during closed mitral valvotomy in patients with chronic rheumatic heart disease, were analysed to determine the frequency of Aschoff nodules and characteristics of mononuclear inflammatory infiltration. Fifty-six percent of specimens demonstrated Aschoff nodules with no clinical or laboratory evidence of acute rheumatic activity in the patients undergoing surgery. Endomyocardial infiltration contained predominantly T cells and occasionally B cells. The relative proportions of T helper-inducer, T suppressor-cytotoxic lymphocytes and macrophages were 45.1 +/- 7.6, 23.5 +/- 4.8 and 29.3 +/- 9.6%, respectively. Frequent presence of Aschoff nodules and heavy mononuclear infiltrates in chronic rheumatic heart disease suggests a possibility of subclinical ongoing carditis.

Fate of mild aortic valve disease after mitral valve intervention

OBJECTIVE

This study was performed to assess the long-term outcome of untreated mild aortic valve disease present at the time of initial mitral valve intervention.

METHODS

A total of 284 patients with rheumatic heart disease aged 7 to 62 years (mean, 23.5 +/- 12.2 years) who underwent mitral valve intervention and had mild aortic valve disease initially were followed up for 2 to 18 years (mean, 10.8 +/- 3.7 years). At initial intervention, 232 patients had pure mild aortic regurgitation, and 52 patients had mild aortic stenosis with or without aortic regurgitation.

RESULTS

Among patients with mild aortic regurgitation initially, 11 (5%) patients progressed to moderate (n = 6) or severe (n = 5) regurgitation over an interval of 9 to 17 years (mean, 12.1 +/- 2.8 years), and 1 patient had moderate aortic stenosis and severe aortic regurgitation after 10 years. Freedom from development of moderate-severe aortic valve disease in patients who initially had mild aortic regurgitation was 100%, 97.0% +/- 1.7%, and 87.4% +/- 4.6% at 5, 10, and 15 years, respectively. Seventeen (35%) patients with initial mild aortic stenosis (with or without regurgitation) had moderate or severe stenosis (with or without moderate-severe regurgitation) after an interval of 4.9 +/- 3.8 years. Freedom from development of moderate-severe aortic valve disease in patients who initially had mild aortic stenosis was 75.6% +/- 6.2%, 61.5% +/- 8.5%, and 46.1% +/- 11.2% at 5, 10, and 15 years, respectively. Ten patients required aortic valve replacement for aortic valve dysfunction.

CONCLUSIONS

Mild aortic regurgitation present at the time of mitral valve intervention progresses very slowly and less frequently requires reintervention. However, mild aortic stenosis diagnosed initially progresses more often and more rapidly and thus needs closer follow-up.

Phenotypic characterization of cellular components of cardiac myxoma: a light microscopy and immunohistochemistry study

Cardiac myxoma is the most common primary tumor of the heart. A detailed evaluation of cell types in 41 cardiac myxomas by light microscopy and in 30 cases by immunohistochemistry was made. Reactivity to the various antisera were observed in the surface lining cells, the stromal myxoma cells and the cells in the perivascular location. Factor VIII-related antigen (FVIIIR-Ag) and Ulex europaeus agglutinin (UEA-1), both endothelial markers, were positive in 23 cases each. UEA-1 was found to be a more sensitive marker than factor VIII. Desmin and myoglobin were positive in 16 and 24 cases, respectively. Reactivity for cytokeratin was noted in ten cases, one of which showed glandular differentiation. Vimentin and S-100 positivity was obtained in 16 and 14 cases respectively. Thus, cardiac myxoma appears to arise from multipotent cells which have the potential to differentiate along several mesenchymal cells or epithelial cells and may also concurrently exhibit reactivity for both mesenchymal and epithelial markers.

Contact leukoderma due to 'Bindi' and footwear

3 cases of contact leukoderma due to 'Bindi' and footwear occurring together in the same patients are reported. In 2 patients depigmentation occurred at the patch test sites with 'Bindi', most probably due to the adhesive in it.

Early removal of catheter following transurethral resection of the prostate

This study was conducted on 83 patients who underwent an uncomplicated transurethral resection of the prostate for carcinoma or benign hyperplasia. In all cases the urethral catheter was removed within 24 h of surgery. Only 2 patients failed to void because of clot retention. The total hospital stay was 3 days in 67 patients. There were no significant complications due to early removal of the catheter.