Conditional engagement of medial frontal cortex during responding under uncertain reinforcement in rats: a paradigm for subjective behavior

Rats were studied for their performance on DRL 10 s and 5 s with 50% probability of reinforcement, before and after medial frontal cortical lesions. A sequential analysis of interresponse times (IRTs) was carried out. It suggested 1. that the medial frontal cortex mediates subjective risk of response choice in rats and 2. that the tolerated risk levels in human decision-making may have a biological basis.

Gaseous transport of volatile organic chemicals in unsaturated porous media: effect of water-partitioning and air-water interfacial adsorption

Laboratory experiments were conducted employing gas chromatographic techniques to evaluate the gaseous transport of volatile organic chemicals (VOCs) in water-unsaturated soil columns as influenced by interfacial (air-water) adsorption and water partitioning. VOCs [methylene chloride, tetrachloroethene (PCE), 1,1,1-trichloroethane (TCA), ethyl-benzene, p-xylene, chlorobenzene] with different water-partitioning and interfacial adsorption coefficients (air-water) were used to evaluate the theoretical basis of using these coefficients to predict the retardation factors (Rt) observed during gaseous transport. A loamy sand from Dover Air Force Base, DE, and a commercial sand were used as the column packing material to assess the effect of grain size on the air-water interfacial area (ai) and retardation at different water saturations (Sw). The ai were measured using n-alkanes. At low Sw, interfacial adsorption contributed most to the retardation for all VOCs during gaseous transport in the Dover soil which has little sorption capacity for the VOCs. As Sw increased, the fraction of Rt attributed to interfacial adsorption decreased, while that due to water partitioning increased for all of the VOCs used for this study. For the sand, with a more uniform grain-size distribution than the Dover soil, the contribution of air-water interfacial adsorption to the Rt of a VOC (p-xylene) was not as significant as that for the Dover soil due to small ai. The fractions of Rt attributed to interfacial adsorption and water partitioning were quantified. The observed Rt for the VOCs agreed well with those predicted based on the sorption coefficients and the quantities of sorption domains (Sw, ai).

Emphysematous urinoma in a renal transplant patient

Urinary infection is a common complication after kidney transplantation. In some instances, especially with Escherichia coli infections, there is formation and collection of gas in the parenchyma and collecting system of the kidney, giving rise to the condition of emphysematous pyelonephritis. Such a process could occur in collections of urine (urinoma) secondary to ureteric leak in the transplant kidney. This process has not been described so far. In this report, we describe the first case of an infected urinoma with an interesting radiologic finding, a so-called emphysematous urinoma.

Carotid artery involvement in patients of atherosclerotic coronary artery disease undergoing coronary artery bypass grafting

BACKGROUND

Patients with concomitant critical carotid and coronary artery disease are at risk of major neurological events while undergoing coronary artery bypass grafting. The presence of carotid artery stenosis increases the stroke rate in the perioperative period. In an effort to reduce the stroke rate, many institutions perform routine preoperative noninvasive assessment of the carotid arteries.

METHODS AND RESULTS

We analyzed the clinical and laboratory data of 1,200 patients who underwent coronary artery bypass surgery in the last 2 years. Carotid Doppler was normal in 186 patients (15.5%), and showed <30% stenosis in 796 (66.3%), 30%-50% in 110 (9.2%), 50%-70% stenosis in 64 (5.3%) and critical (>70%) stenosis in 44 (3.7%) patients. Conventional risk factors such as hypercholesterolemia, hypertension, smoking and family history were not independent predictors of carotid artery stenosis. However, diabetes as a risk factor had a significant association with carotid artery disease (79.6% v. 43.8%, p<0.02). There was a trend towards increased prevalence of carotid artery stenosis in patients with > or = 2 risk factors (84.3% v. 68.8%). Patients with significant carotid artery stenosis had severe coronary artery disease (triple-vessel disease 93.3%, left main coronary artery disease 12.0%). Out of 44 patients with critical carotid artery stenosis, 27 were subjected to carotid angiography. Doppler findings correlated well with angiography. Seventeen patients underwent carotid artery intervention. None had any perioperative neurological events. A total of 5 (0.4%) patients had a major stroke. Coronary artery bypass grafting was done in 27 patients with critical stenosis without any intervention. The stroke rate (11.1%) was higher in these patients compared to patients with < 70% carotid artery disease or post-carotid intervention (2.5%) patients. Thus, untreated >70% carotid artery stenosis was associated with a higher stroke rate.

CONCLUSIONS

Doppler screening of the carotid artery is helpful in detecting the subgroup of patients at increased risk of stroke. Patients with critical carotid artery stenosis should be subjected to angiography. Prophylactic intervention may reduce the occurrence of stroke in the perioperative period.

Platypnea-orthodeoxia: management by transcatheter buttoned device implantation

Dyspnea and arterial desaturation on upright position in elderly subjects is described as platypnea-orthodeoxia syndrome (POS) and in some patients it is due to right-to-left shunt across the atrial septal defect (ASD)/patent foramen ovale (PFO). Surgical closure of ASD/PFO has been the only available treatment option. Buttoned device has been used for occlusion of ostium secundum ASD, PFO associated with presumed paradoxical embolism and cerebrovascular accidents and ASD/PFO in association with other congenital heart defects causing right-to-left shunt. The objective of this article is to describe the use of buttoned device in effectively occluding ASD/PFO to relieve hypoxemia of POS. During a 4-year period ending January 2000, 10 patients, ages 71 +/- 9 (range 60-83) years with POS underwent buttoned device closure of their ASD/PFO. Echocardiographic and balloon-stretched atrial defect sizes were 8 +/- 3 mm and 12 +/- 3 mm, respectively. The ASD/PFO were occluded with devices ranging in size from 25 to 40 mm delivered via 9 French, long, blue Cook sheaths; eight had an additional 25- or 35-mm occluder placed on the right atrial side. The oxygen saturation increased (P < 0.001) from 76 +/- 7% (range 69-86%) to 95 +/- 2% (range 92-98%). No complications were encountered. Relief of symptoms was seen in all patients. Follow-up of 1-36 months (median 12 months) revealed persistent improvement of symptoms. Buttoned device occlusion of ASD/PFO to relieve hypoxemia of POS is feasible, safe, and effective and is an excellent alternative to surgery. Cathet Cardiovasc Intervent 2001;54:77-82.

Evaluation of remediation performance and cost for field-scale single-phase microemulsion (SPME) flushing

Pump-and-treat strategies employed to contain contaminant plumes have been demonstrated to be inefficient, and often ineffective, for remediation of aquifers contaminated by nonaqueous phase liquids (NAPLs). This has prompted the development of alternative technologies to provide enhanced remediation of NAPL source zones. The results reported here are from a solubilization study wherein the objective was to achieve high NAPL remediation efficiencies using a low concentration of chemical additives in the flushing solution. A surfactant/alcohol mixture was used to generate a Winsor Type I system, where the NAPL was solubilized and transported as a single-phase microemulsion (SPME). For the SPME process, only 5.5 wt% of the flushing solution comprised chemical additives. The costs associated with this project are discussed and approaches aimed at reducing costs are suggested.

Achalasia in siblings in infancy

Achalasia is rare in children, more so familial. We report two siblings with familial achalasia who presented in their infancy with vomiting and failure to thrive. Achalasia can be misdiagnosed as upper gastrointestinal obstruction as happened in one of our siblings. Esophageal contrast roentgenography is diagnostic. Both the children were treated successfully by transabdominal esophagomyotomy with fundoplication.

Spectral investigations on melanterite mineral from France

EPR, Optical and IR spectral studies on a naturally occurring mineral melanterite are carried out at room temperature. EPR studies indicate the presence of Cu(II) ion in tetragonally distorted octahedral site and hyperfine lines could not be resolved due to higher concentration of the paramagnetic impurity in the mineral. Optical absorption spectrum is a characteristic of Fe(II) and Cu(II) ions. Crystal field parameters are evaluated. IR spectrum confirms the presence of water and sulphate ions.

99mTc labeled VIP analog: evaluation for imaging colorectal cancer

Early and reliable diagnosis of colorectal cancer continues to be demanding and challenging. Colorectal cancer cells express Vasoactive Intestinal Peptide (VIP) receptors in high density. We have prepared a VIP analog (TP3654), labeled it with (99m)Tc, and evaluated it in experimental animals as an agent for imaging colorectal cancer. The tissue distribution of (99m)Tc-TP3654 has been compared with that of (111)In-DTPA-Octreotide and (99m)Tc-anti-CEA scan in nude mice bearing human colorectal cancer LS174T. Finally, pharmacokinetic and tissue distribution studies of (99m)Tc-TP3654 have been performed in four normal human volunteers. Data suggest that (99m)Tc-TP3654 can be prepared efficiently without loss of its receptor specificity and biological activity. Although the 24 hr tumor uptake of (99m)Tc-TP3654 in the animal model used was modest (0.21 +/- 0.07% I.D./g), the tissue distribution profile was more favorable than that of (111)In-DTPA-Octreotide or (99m)Tc-anti-CEA scan. Human studies indicated that (99m)Tc-TP3654 had no adverse effect in any subject. Within 24 hours, approximately 70% of the injected dose cleared through the kidneys, and approximately 20% through the hepatobiliary system. In these non-fasting volunteers hepatobiliary clearance was slow and in cancer patients tumor uptake was rapid. Data suggest that (99m)Tc-TP3654 is a promising agent for imaging colorectal cancer.

The Sideris buttoned devices for transcatheter closure of patent ductus arteriosus

This article reviews the experience in the last decade with Sideris buttoned devices for occlusion of patent ductus arteriosus (PDA). The devices used were the regular buttoned device, the infant buttoned device, the device with the folding plug, and the wireless device. The buttoned devices were implanted transvenously and introduced through 7Fr-8Fr long sheaths for PDAs up to 12 mm; wireless devices required 9Fr-11Fr sheaths for PDAs up to 22 mm. All different shapes of ductus were occluded. The records of 356 patients in the international and Food and Drug Administration (FDA) supervised United States (US) clinical trials were reviewed. Despite excellent long-term full occlusion rates and the absence of significant complications with the regular buttoned device, modifications were necessary to improve the full occlusion rates in 24 hours. The 24-hour rates improved from 60% with the regular device to 85% with the folding plug device. Most residual shunts disappeared on long-term follow-up without significant complications. Wireless devices were developed for very large PDAs and have excellent occlusion rates. The buttoned device with the incorporated folding plug and the wireless devices are currently under clinical trial. The safety record of the new devices needs to be established with larger clinical trials.

Olecranon stress fracture in a weight lifter: a case report

Stress fractures have been reported in the upper limb of sportspeople involved in upper limb dominated events. Olecranon stress fractures have been cited in baseball pitchers, javelin throwers, and gymnasts. The unusual case of a stress fracture of the olecranon in a young weight lifter is reported here. The minimally displaced stress fracture was treated with tension band and two Kirschner wires. The fracture healed in four months and the patient returned to light sports activity after six months.

Centering-on-demand buttoned device: its role in transcatheter occlusion of atrial septal defects

Since the initial design and description of the buttoned device, it has undergone a number of design changes. Introduction of radiopacity in the knot (button) made it easier to visualize and document that buttoning has indeed occurred. Introduction of two buttons has markedly decreased the unbuttoning rate with potential for eliminating it. A centering mechanism was then incorporated into the device, which allowed closure of larger defects and use of smaller-sized devices. For some unknown reason, unbuttoning rate no longer occurs since the introduction of this device. The centering-on-demand (COD) device also appears to have increased the effective occlusion rates. At the present time, however, no long-term follow-up data are available to assess the long-term efficacy of the new device. Experience in a larger number of patients and evaluation of follow-up data are necessary to confirm the safety and efficacy observed in the small cohort reported in this review.

Coil occlusion of patent ductus arteriosus associated with right aortic arch

Two children with patent ductus arteriosus and associated right aortic arch underwent successful transcatheter coil occlusion. Recognition of ductal anatomy and ensuring that no symptomatic vascular ring is present are important prior to embarking on ductal occlusion. It is concluded that coil occlusion of patent ductus arteriosus in association with right aortic arch is feasible, safe, and effective.

Single crystal EPR study of VO(II)-doped magnesium

Single crystal EPR studies of VO(II)-doped magnesium potassium Tutton's salt have been carried out at room temperature. The results indicate that the paramagnetic impurity has entered the lattice, both substitutionally and interstitially and the maximum hyperfine for the substitutional site along the a axis corresponds to the minimum hyperfine for interstitial site and vice versa. The spin Hamiltonian parameters obtained from single crystal data for these sites are: Site 1, gparallel = 1.954(1); gperpendicular = 1.998(1), Aparallel = 19.80(2) mT; Aperpendicular = 7.61(2) mT; Site 2, gparallel = 1.997(1); gperpendicular = 1.952(1), Aparallel = 7.66(2) mT; Aperpendicular = 19.85(2) mT. Superhyperfine from ligand protons have been observed at certain orientations for Site 2 impurity. Powder spectrum shows a set of eight parallel and perpendicular features indicating the presence of only one site and these values matched with Site 1 values. From these observations, it has been concluded that the two vanadyl impurities are approximately at right angles to each other. Cooling the sample to 77 K does not change the spectra appreciably. The admixture coefficients have been calculated from Site 1 data, which agree well with the reported values.

Nitric oxide (NO) and interleukin-1beta (IL-1beta) in follicular fluid and their correlation with fertilization and embryo cleavage

PROBLEM

Using an IVF model, the goal of the study was to investigate the relationship between follicular fluid (ff) NO and IL-1beta levels, as well as their correlation with fertilization of mature oocytes and embryo cleavage rates.

METHOD OF STUDY

Follicular fluid was collected from 17 patients at the time of transvaginal oocyte retrieval following controlled ovarian stimulation. Oocytes harvested from these follicles were followed through fertilization and embryo cleavage. The NO metabolites nitrate/nitrite (NO3/NO2) were measured using the Griess reaction as an indirect assessment of NO activity. IL-1beta was measured using a high sensitivity ELISA system (Amersham, UK). The Student's t-test was utilized for unpaired data with the means considered significantly different when P < or = 0.05.

RESULTS

Follicular fluid NO3/NO2 levels were significantly lower in follicles containing mature oocytes that fertilized (n = 30; 9.7 +/- 1.0 microM), versus those that did not fertilize (n = 23; 15.4 +/- 2.4 microM; P < 0.05). Follicles that contained oocytes that fertilized and went on to divide beyond the 6 cell stage had significantly lower ff levels of NO3/NO2 (n = 18; 7.5 +/- 0.9 microM), as compared to ff that contained oocytes that did not fertilize or failed to develop beyond the 5 cell stage (n = 35; 14.6 +/- 1.7 microM; P < 0.01). No correlation was found between ff NO3/NO2 levels (n = 28; 13.8 +/- 2.0 microM) and ff IL-1beta levels (n = 28; 0.5 +/- 0.08 pg/mL). An analysis of ff IL-1beta levels in relation to fertilization and embryo cleavage rates revealed no correlation.

CONCLUSIONS

Lower ff NO3/NO2 levels at the time of oocyte retrieval are associated with adequate fertilization and embryo cleavage rates. In our IVF model, no correlation was found between ff IL-1beta levels and ff NO3/NO2, fertilization, or embryo cleavage rates.

Pulmonary Stenosis

Balloon valvuloplasty provides optimal treatment for moderate and severe pulmonary valve stenosis. Dysplastic pulmonary valves may not respond to balloon dilation and frequently require surgical treatment. Balloon angioplasty with or without stenting is the preferred treatment of peripheral pulmonary stenosis.

A receptor-specific peptide for imaging infection and inflammation

The chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (fMLP), when radiolabelled, continues to be an attractive agent for imaging infection or inflammation. Previously, several analogues of fMLP have been prepared and radiolabelled using a bifunctional chelating agent conjugation procedure that was relatively long and complex. We have prepared a new analogue of fMLP, TP765, by the addition of 4-aminobutyric acid (4-ABA) and a group of four amino acids, Gly-Gly-d-Ala-Gly, to the carboxy terminus (i.e. to the phenylalanine) of fMLP. The adduct -(4-ABA)-Gly-Gly-d-Ala-Gly- serves as a chelating moiety for strong chelation with 99Tcm. The use of a peptide as a chelating moiety greatly simplified the synthetic procedure and rendered the analogue ready for instant chelation with 99Tcm. HPLC analysis revealed that 99Tcm-TP765 was a single chemical entity that retained biological activity and neutrophil specificity. 99Tcm-TP765 was stable when challenged with strong chelating agents in vitro and had rapid but biphasic blood clearance (alphat1/2 = 7 min, betat1/2 = 45 min). Approximately 90% of the radioactivity had cleared from circulation within 45 min post-injection and the agent had accumulated in experimental bacterial or sterile abscesses in significantly (P<0.05) higher quantities than the analogues evaluated previously. Generally, the biodistribution pattern of 99Tcm-TP765 was similar to that of other analogues examined and its abscess uptake was independent of the abscess age. In conclusion, a new analogue of fMLP, 99Tcm-TP765, was prepared by a simple procedure. This new analogue has properties similar to those of previously examined analogues used as agents for imaging infection or inflammation.

Results of transvenous occlusion of secundum atrial septal defects with the fourth generation buttoned device: comparison with first, second and third generation devices. International Buttoned Device Trial Group

OBJECTIVES

The purpose of this study was to assess safety and effectiveness of the fourth generation buttoned device in dosing atrial septal defects (ASDs) and to test the hypothesis that introduction of double button reduces unbuttoning rate without reducing effectiveness.

BACKGROUND

Because of the high unbuttoning rate (7.2%) with first, second and third generation buttoned devices, the device was modified (fourth generation) so that there were two radiopaque spring buttons 4 mm apart on the button loop attached to the occluder.

METHODS

During a four-year period ending in September 1997, 423 patients, ages 1.5 to 80 years (median 16 years), underwent closure of ASD at 40 medical centers around the world.

RESULTS

The ASD size varied between 5 and 30 mm (median 17 mm). The device size varied between 25 and 60 mm. Unbuttoning occurred in 4 (0.9%) of 423 patients. Effective occlusion, defined as no (n = 343) or trivial (n = 34) residual shunt on echo-Doppler studies performed within 24 h of the procedure, was demonstrated in 377 patients (90%). Thus, the unbuttoning rate (0.9 vs. 7.2%) decreased (p<0.01) while effective occlusion rate (90 vs. 92%) remained unchanged (p>0.1) with this device, compared with earlier generation devices. During follow-up from one month to five years (23+/-15 months), 21 (5%) of 417 patients required surgical (n = 12) or transcatheter (n = 9) reintervention, mostly to treat significant residual shunt. In the remaining patients there was gradual reduction and disappearance of the residual shunt. No wire integrity problems were observed.

CONCLUSIONS

These data suggest that the fourth generation buttoned device is as effective as earlier generation devices, but without significant unbuttoning. Follow-up results remained good, with a reintervention-free rate of 89% at five years.

Leprosy affected beggars as a hidden source for transmission of leprosy

BACKGROUND & OBJECTIVES

Despite the large scale implementation of multidrug therapy (MDT), the incidence rates of leprosy have not declined in several hyperendemic countries. Before searching for non-human reservoirs of leprosy it would be necessary to look for hidden human sources. This would include destitute leprosy affected persons who resort to begging and operate in congested areas. Hence this study was undertaken.

METHODS

One major town and three semi-urban areas in Vellore district of Tamil Nadu and Chittoor town in Andhra Pradesh were purposefully selected for the study. All beggars in these towns were systematically identified and examined by allopathic doctors. Skin smears were examined for bacteriological index.

RESULTS

Among the 193 beggars screened, 58 had leprosy. Of these 10 were smear positive. Several beggars, although living separately, were in touch with their relatives. Most beggars were pavement dwellers and regularly begged at places of worship, bus stands and shopping centres.

INTERPRETATION & CONCLUSION

The fact that nearly 20 per cent of the leprosy affected beggars were skin smear positive highlights the need for regular screening and treatment of such beggars. Those positive should be actively treated and their close contacts frequently screened. This hidden reservoir should be completely eliminated.

In vitro susceptibility testing of nonsporing anaerobes to ten antimicrobial agents

Antibiotic susceptibility was performed on sixty clinical isolates of nonsporing anaerobes against ten antimicrobial agents. The test was performed on Muller Hinton Agar and Wilkins Chalgren blood agar by preparing suspension of freshly isolated colonies in BHI broth. Apart from Metronidazole and Chloramphenicol newer antibiotics like Minocycline, Secnidazole, Tinidazole, Clarithromycin, Roxithromycin were also tried. Antimicrobial agents like Metronidazole, Secnidazole, Tinidazole and Minocycline were 100% sensitive, followed by Chloramphenicol, Clarithromycin and Roxithromycin. These newer agents can be good alternatives for the treatment of non sporing anaerobes.

The 'consciousness primitive': a competence model of mind and will

Questions about mind and will are usually raised as though mind and will are either present or absent. Here, a view is presented to suggest that they are only a particular instantiation of a 'consciousness primitive', present in lower animals as well as in primitive portions of the human brain. Physiological variables, drugs and transmitters alter it in order to produce discontinuous products, such as learning, motivation, emotions etc., which are usually studied by performance models as though they are distinctive functions of the brain.

Five-loop coil occlusion of patent ductus arteriosus prevents recurrence of shunt at follow-up

Recent reports suggest reopening of the patent ductus arteriosus (PDA) after complete occlusion with three-loop Gianturco coils. We hypothesize that five-loop coils may produce a larger thrombus than three-loop coils, which will result in no or less probability of recanalization of PDA during follow-up. This study is designed to test this hypothesis. Follow-up echocardiographic and Doppler data of 30 patients who underwent five-loop coil occlusion of small to medium-sized PDA during a 33-month period ending December 1998 were examined. Thirty patients had no residual shunt on echo Doppler study on the day following the procedure and were followed for 6 to 30 months (median, 12) after coil implantation. At the last follow-up study, none of the patients had a residual shunt and left atrial size decreased. Careful pulsed, continuous wave, and color Doppler interrogation of left/main pulmonary artery junction and proximal descending aorta did not reveal any evidence for obstruction. The follow-up data suggest that complete occlusion of small- to medium-sized PDAs is feasible with five-loop coils without evidence for recanalization at a mean follow-up of 12 months. Much longer (2 to 5 years) follow-up data may be necessary to confirm these observations. We speculate that a greater degree of thrombosis is produced within the ductus by the five-loop coils, which in turn may be responsible for lack of shunt recurrence. We recommend use of five-loop instead of three-loop coils for transcatheter occlusion of small- to medium-sized PDAs.

In vitro susceptibility testing of nonsporing anaerobes to ten antimicrobial agents

Antibiotic Susceptibility was performed on sixty clinical isolates of nonsporing anaerobes against ten antimicrobial agents. The test was performed on Muller Hinton Agar and Wilkins Chalgren blood agar by preparing suspension of freshly isolated colonies in BHI broth. Apart from Metronidazole and Chloramphenicol newer antibiotics like Minocycline, Secnidazole, Tinidazole, Clarithromycin, Roxithromycin were also tried. Antimicrobial agents like metronidazole, Secnidazole, Tinidazole and Minocycline were 100% sensitive, followed by Chloramphenicol, Clarithromycin and Roxithromycin. These newer agents can be good alternatives for the treatment of non sporing anaerobes.

Pulmonary endothelial and epithelial integrity and neutrophil infiltration after endotoxin in interleukin-1 receptor knockout mice

Previously we found the structural integrity of the aortic endothelium was maintained after the administration of endotoxin in type 1 interleukin-1 (IL-1) receptor knockout mice. In this study, we investigated further the integrity of pulmonary vascular endothelium, airway epithelial, pulmonary microvasculature, and neutrophil infiltration into the microvasculature and respiratory air spaces. Adult male C57BL/129J wild-type mice and C57BL/129J knockout mice possessing a homozygous deletion of the type 1 IL-1 receptor received the following intraperitoneal injections; 1) Escherichia coli endotoxin (ENDT) (10 mg/kg), 2) ENDT (2 mg/kg given for 4 days), or (3) saline vehicle. Wild-type and knockout control animals receiving saline vehicle showed normal endothelial and epithelial ultrastructure with intact membranes. Pulmonary endothelial cell damage was found only in wild-type mice given a single 10 mg/kg endotoxin dose. Airway epithelial damage was found only in wild-type mice given a repetitive dose of endotoxin (2 mg/kg for 4 days). Neutrophil infiltration increased only in mice given a single dose of endotoxin (10 mg/kg) with the wild-type increasing by 32% and the knockouts by 6% compared with the saline control for that group respectively. Serum IL-6 and nitric oxide (indicators of septic shock severity and lethality) significantly increased only in the mice given 10 mg/kg of endotoxin. The maintenance of pulmonary endothelial and epithelial cell integrity and the decrease of neutrophil infiltration in the IL-1 knockout mice suggest that IL-1 contributes significantly to the severity of endotoxin-induced sepsis.

In Vitro Production Of L-dopa In Tissue Cultures Of Banana

Shoot and callus cultures of banana ( Musa sp.) were analyzed for the accumulation of L-DOPA. Treatment of cultures with L-tyrosine and L-phenylalanine yielded higher levels of DOPA compared to those in control cultures without any treatment. Among the two amino acids, phenylalanine induced higher accumulation of DOPA. The study suggests that banana may become an useful system for the production of DOPA.

Imaging vascular thrombosis with 99mTc-labeled fibrin alpha-chain peptide

An agent that permits scintigraphic detection of chronic deep venous thrombosis (DVT) or pulmonary embolism (PE) would be a welcome addition to the armamentarium of nuclear medicine. Because fibrin is the integral part of each clot, old or fresh, we hypothesized that a 99mTc-labeled fibrin alpha-chain N-terminal peptide, Gly-Pro-Arg-Pro-Pro, that binds to the C-terminal portion of the gamma-chain of fibrin can detect DVT and PE.

METHODS

The peptide was modified to Gly-Pro-Arg-Pro-Pro-Aba-Gly-Gly-(D)-Ala-Gly to permit efficient binding of 99mTc (99mTc-TP 850). The stability of the peptide was examined in vitro as well as in vivo. The ability of the agent to bind to rabbit, dog, and human fibrin and to inhibit adenosine diphosphate-induced platelet aggregation was examined. Blood clearance and 3-h tissue distribution were studied. DVT was induced in 8 rabbits using a stimulating electrode and in 2 rabbits by inserting a thrombin-soaked suture. PE was induced in 6 additional rabbits by introducing tantalum-impregnated blood clots into the right atrium, and the rabbits were radiographed to locate the emboli. 99mTc-TP 850 was then injected through a lateral ear vein, and each rabbit was imaged for up to 3 h. The rabbits were then killed, the heart and lungs were dissected and radiographed and the clots were harvested so that clot-to-blood radioactivity ratios could be determined.

RESULTS

The peptide analog permitted efficient incorporation of 99mTc, which was stable in vitro and in vivo. The blood clearance was biphasic, with an alpha phase half-life of approximately 4 min (20%) and a beta phase half-life of approximately 13 min (88%). The mean binding of 99mTc-TP 850 to human, dog, and rabbit fibrin was 46% +/- 2%, 60% +/- 3%, and 56% +/- 2.5%, respectively, and the inhibitory concentration of 50% for dog and rabbit platelet aggregation was 236 pm and 167 pm, respectively. All clots, including 24-h-old pulmonary emboli, were delineated. The radioactivity associated with clots varied from 0.01 to 0.09 %ID/g, with clot-to-blood radioactivity ratios ranging from 1.2 to 12.0. However, 48-h-old pulmonary emboli had lysed and were seen neither by radiography nor by scintigraphy.

CONCLUSION

A fibrin alpha-chain, N-terminal peptide that binds to the C-terminal portion of the gamma-chain of fibrin has been modified and labeled with 99mTc. The resultant peptide is stable in vitro and in vivo; binds to human, dog, and rabbit fibrin in large quantities; and inhibits platelet aggregation. The peptide clears rapidly from the blood and delineates experimental DVT and PE in rabbits. This agent is worthy of further investigation.

Balloon angioplasty of long-segment aortic coarctation in the neonate

It is generally believed that balloon angioplasty of diffuse, long-segment aortic coarctation is not effective. In this report, we describe two neonates with diffuse, long-segment coarctation in association with complex congenital heart defects in whom we were successful in effectively treating coarctation with transumbilical artery balloon angioplasty. Based on this experience, it may be concluded that balloon angioplasty of long-segment coarctation in neonates is feasible and effective, but confirmation in a larger group of patients may be necessary prior to general adoption of this concept.

Fluoroscopically-guided manipulation of malfunctioning peritoneal dialysis catheters

OBJECTIVE

To review our experience with fluoroscopic evaluation and manipulation of malpositioned, malfunctioning, peritoneal dialysis (PD) catheters.

MATERIALS AND METHODS

Thirty-one patients, over a 5-year period (1 May 1992 to 30 April 1997) with malfunctioning PD catheters, who had fluoroscopically-guided manipulation were reviewed. Catheters were manipulated using a malleable aluminum bar and, if necessary, guide wires or other stiffeners. Technical success was assessed on the basis of adequate, fluoroscopically verified, catheter placement at the time of the procedure and improved flows. A functional PD catheter at 30 days post manipulation was considered to be a clinically successful manipulation.

RESULTS

There were 41 manipulations [33 initial (IM) and 8 remanipulations (RM)] for malpositioned or kinked catheters. In 31 (19 male, 12 female) patients ranging in age from 31 to 76 years (mean age 60 years), the initial technical success rate was 85% for IM (n = 28/33) and 63% (n = 5/8) for RM. The overall clinical success rate, or 30-day primary patency, was 55% for IM (n = 18/33) and 63% for RM. Catheter function (combined IM and RM) continued for a median 869 days (95% CI: 118, 1620). No early complications were noted.

CONCLUSIONS

Fluoroscopic manipulation, including attempts at remanipulation, of PD catheters is a safe procedure. The technique is a simple, inexpensive, and effective way of prolonging PD catheter life, thereby reducing the number of surgical interventions.

Effect of thiocyanate induced hypothyroidism on 5'deiodinase activity and T3 receptors in developing rat brain

Experiments were performed in weaning rats to understand the influence of thiocyanate, an hydrolytic product of glucosinolates present in foods, on the generation of T3 in situ by type II 5'deiodinase and the binding of 125I T3 to specific nuclear receptors in developing brain. Feeding of thiocyanate through gestation and lactation resulted in an increase in type II 5'deiodinase activity in cerebrum, cerebellum and brainstem of the 21 day old pups compared to controls. Hypothyroidism induced by thiocyanate further resulted in augmentation of the maximum binding capacity of receptors in the cerebrum of the weaning pups. Affinity constants for binding of 125I T3 were however, unaltered. Increase in type II 5'deiodinase activity and the number of binding sites point to an adaptive increase in response to thiocyanate induced hypothyroidism to maintain the cellular T3 levels within a narrow limit.

Burkholderia pseudomallei--abscess in an unusual site

Meloidosis in a unusual site has been reported in a child. Complete identification of the organism has been presented.

Nasal mucosa and skin of smear-positive leprosy patients after 24 months of fixed duration MDT: histopathological and microbiological study

The skin and nasal mucosa of 10 lepromatous leprosy patients who had completed 24 doses of fixed duration multidrug therapy (MDT) but who continued to be skin-smear positive for acid-fast bacilli (AFB) were examined histopathologically. The nasal mucosa showed granuloma fractions that exceeded those seen in the skin specimens, signifying that activity in this region subsides much more gradually than the activity in the skin. Mouse foot pad studies done using T900r mice with an inoculum from the nasal mucosa biopsy specimens of these patients did not demonstrate any growth of Mycobacterium leprae, indicating that these bacilli were not viable. A skin specimen from one patient grew significant amounts of bacteria in the T900r mouse foot pad. These results show that 2 years of treatment with MDT would prevent dissemination of M. leprae from the nasal mucosa and, therefore, should preclude further transmission of the disease. It also indicates that viable bacteria might persist in the skin of patients, especially those with an initial bacterial index of > or = 4+ who have completed 24 doses of regular MDT. Therefore, a more cautious approach to administering only 12 doses of MDT to highly positive multibacillary patients is suggested.

Long-term follow-up results after balloon dilatation of pulmonic stenosis, aortic stenosis, and coarctation of the aorta: a review

Although immediate and intermediate-term results after balloon dilatation of congenital stenotic lesions of the heart in children are well studied, long-term results have not been documented. Therefore, we reviewed our experience along with the limited published data to address this issue. Late follow-up after balloon pulmonary and aortic valvuloplasty shows low-residual gradients, reintervention-free rates in the mid-80s for pulmonic and in the mid-50s for aortic stenosis, and an increase in degree and prevalence of similunar valve insufficiency. Balloon angioplasty of aortic coarctation results in low-residual gradients, residual hypertension in a minority of patients, low prevalence of aneurysms, and high rates of recurrence in the neonate and young infant. Overall, balloon dilatation is a useful technique in relieving congenital obstructive lesions of the heart in the pediatric patient, but continued study of (1) late pulmonary and aortic insufficiency after valvuloplasty, (2) recurrence and aneurysms after balloon angioplasty of coarctations and, (3) femoral artery compromise in lesions requiring transfemoral artery approach is warranted.

Being a female leprosy patient in south India

The problems of women patients as revealed by a case study of a woman patient and a questionnaire study of 100 leprosy patients (47 men and 53 women) are presented. These include, besides general ones like ignorance of facts about the disease, specific ones like lack of privacy during clinical examination, indifference towards women's feelings and difficulties in communicating with male workers. A greater sensibility towards the sentiments and problems of women patients, on the part of the health service is required to amend the situation. Recruiting more women workers might help in this regard.