Flight trajectory analysis of CuSn-droplets generated by laser drop on demand jetting, using stereoscopic high-speed imaging

Laser drop on demand jetting of Cu-base braze droplets was proven a suitable method for joining wires to electrode structures of electronic devices, particularly if the electrical contacts need to withstand high thermal loads. During joining, a braze preform of 600 µm diameter is placed inside a capillary, molten by a laser pulse and subsequently ejected from the capillary by inert gas overpressure similarly to conventional solder ball bumping processes. However, since the liquidus temperature of the used braze material of 990 °C is about 760 °C higher than of standard Sn-based solders used in electronics packaging, the system technology was modified significantly to enable jetting of CuSn alloys. In particular, the beam source emits a five times higher optical output power than standard machines designed for processing Sn-based solders. In addition, a modified capillary made from technical ceramic was machined, to withstand the significantly higher heating- and cooling rates during the process. In order to understand the influence of capillary geometry on droplet detachment, and flight trajectory, two capillary geometries were machined applying a picosecond laser ablation process. Subsequently, stereoscopic high speed videos of droplet detachment and flight phase were analyzed. Using this approach it is possible, to determine droplet flight trajectories, velocities and lateral positional deviations in dependency of relative inert gas overpressure inside the machining head, pulse power and capillary geometry. The findings indicate a significant influence of the capillary geometry and the applied overpressure on the droplet flight trajectory, whereas the role of the laser pulse power seems neglectable.

Exploring the efficacy and cellular uptake of sorafenib in colon cancer cells by Raman micro-spectroscopy

This study demonstrates the efficacy and distribution of sorafenib in colon cancer cells by label-free Raman microscopy.

Linear stapled gastrojejunostomy results in fewer strictures compared to circular stapled gastrojejunostomy in laparoscopic gastric bypass surgery

PURPOSE

Currently, there are two laparoscopic stapling techniques to perform the gastrojejunostomy in gastric bypass surgery: the linear stapling and circular stapling techniques. The aim of the study was to compare the two techniques regarding postoperative morbidity and weight loss at an accredited bariatric reference center in Switzerland.

METHODS

We compared two consecutive cohorts at a single institution between November 2012 and June 2014 undergoing laparoscopic gastric bypass surgery. The frequency of complications and weight loss at 1 year was assessed in 109 patients with the 21-mm circular stapling technique (CSA) and 134 patients with the linear stapling technique (LSA).

RESULTS

Postoperative complications were more frequent in the CSA group with 23.9 versus 4.5% in the LSA group (p = <0.0001). The main difference was the frequency of strictures, which occurred in 15.6% in the CSA group versus 0% in the LSA group. As a result, endoscopic dilation was required at least once in 15 patients. There was no statistically significant difference in percentage of excessive weight loss (EWL) in both groups; EWL was 74% in the CSA group and 73% in the LSA group (p = 0.68).

CONCLUSION

Linear stapled laparoscopic gastric bypass had fewer stenotic strictures with similar weight loss at 1 year compared to circular stapling technique.

Sample preparation method for glass welding by ultrashort laser pulses yields higher seam strength

Glass welding by ultrashort laser pulses allows joining without the need of an absorber or a preheating and postheating process. However, cracks generated during the welding process substantially impair the joining strength of the welding seams. In this paper a sample preparation method is described that prevents the formation of cracks. The measured joining strength of samples prepared by this method is substantially higher than previously reported values.

Lipases provide a new mechanistic model for polyhydroxybutyrate (PHB) synthases: characterization of the functional residues in Chromatium vinosum PHB synthase

Polyhydroxybutyrate (PHB) synthases catalyze the conversion of beta-hydroxybutyryl coenzyme A (HBCoA) to PHB. These enzymes require an active site cysteine nucleophile for covalent catalysis. A protein BLASTp search using the Class III Chromatium vinosum synthase sequence reveals high homology to prokaryotic lipases whose crystal structures are known. The homology is very convincing in the alpha-beta-elbow (with the active site nucleophile)-alpha-beta structure, residues 131-175 of the synthase. A conserved histidine of the Class III PHB synthases aligns with the active site histidine of the lipases using the ClustalW algorithm. This is intriguing as this histidine is approximately 200 amino acids removed in sequence space from the catalytic nucleophile. Different threading algorithms suggest that the Class III synthases belong to the alpha/beta hydrolase superfamily which includes prokaryotic lipases. Mutagenesis studies were carried out on C. vinosum synthase C149, H331, H303, D302, and C130 residues. These studies reveal that H331 is the general base catalyst that activates the nucleophile, C149, for covalent catalysis. The model indicates that C130 is not involved in catalysis as previously proposed [Müh, U., Sinskey, A. J., Kirby, D. P., Lane, W. S., and Stubbe, J. (1999) Biochemistry 38, 826-837]. Studies with D302 mutants suggest D302 functions as a general base catalyst in activation of the 3-hydroxyl of HBCoA (or a hydroxybutyrate acyl enzyme) for nucleophilic attack on the covalently linked thiol ester intermediate. The relationship of the lipase model to previous models based on fatty acid synthases is discussed.

Donor factor V Leiden mutation and vascular thrombosis following liver transplantation

The most commonly detected hypercoagulable state involves an abnormal factor V protein synthesized by the liver in which arginine at position 506 is replaced by glutamine as a result of a single-point mutation in the factor V gene (factor V Leiden). Liver transplantation is complicated by hepatic vascular thrombosis in up to 15% of cases, resulting in graft loss in most instances. This retrospective study examined the effect of the factor V Leiden mutation on the risk of hepatic vessel thrombosis after liver transplantation. The mutation was sought by polymerase chain reaction and Mnl I digestion of DNA where available from 214 recipients and 276 donors receiving 319 liver transplants. No donors or patients were homozygous for the factor V Leiden mutation. The prevalence of the heterozygous mutation was 19 of 276 (6.9%) in donors and 19 of 214 (8.9%) in recipients. Forty-one thrombotic episodes occurred after transplantation in the 276 transplants in which donor DNA was available for analysis; 22 involved the hepatic artery, 9 involved the portal vein, and 10 were deep venous thromboses. A donor factor V Leiden mutation was detected in the donor in 6 of 41 (14.6%) with any thrombotic event compared with 13 of 235 (5.5%) without (P = 0.03). The relative risk of any thrombosis with this mutation was therefore 2.32 (95% confidence interval [CI], 1.12-4.81). The factor V Leiden mutation was present in the donor in 4 of 31 (12.9%) cases complicated by hepatic vessel thrombosis (which always led to graft loss or death) and 15 of 245 (6.1%) cases without (P = 0.16). The relative risk of hepatic vessel thrombosis in the presence of this allele was therefore 2.00 (95% CI, 0.78-5.14). As anticipated, the presence of this allele in the recipient was not associated with deep venous or hepatic vessel thrombosis. The factor V Leiden mutation in the donor liver is not a major risk factor for hepatic vessel thrombosis and subsequent graft loss after liver transplantation.

[Passive smoking in the workplace: a survey in the Zurich University Hospital]

The consequences of involuntary smoking are well documented. We conducted a survey among all employees of the University Hospital, Zurich, to assess their smoking habits and feelings about restrictions or a ban on smoking. In March 1995, a questionnaire was mailed to all 5230 hospital employees, 2620 (50.1%) completed forms were sent back. 76% of all staff are confronted with cigarette smoke during their worktime. 83% of these employees are distressed by tobacco smoke, and 43% feel that involuntary smoking affects their health. 19% of all employees are smokers. 19% of these are distressed by smokers at work themselves, whereas 13% feel that they are discriminated against by non-smokers. Restriction to designated smoking rooms (68%) or a ban on smoking (27%) would be supported by 95% of all employees. Even 89% of the smokers support smoking restrictions. These results show that there is a considerable demand for a smoke-free working environment among university hospital staff.

Advance directive decision making among medical inpatients

Per the Patient Self-Determination Act of 1991, hospitals are required to ascertain whether patients have an advance directive (AD). At this point, factors prompting patients to issue ADs have not been studied. The purpose of this study was to describe patients' understanding of ADs as well as the process patients used to arrive at their decisions to implement an AD. A stratified random sample of 26 patients from two intensive care units, one general medical unit, one general cardiac unit, and one acquired immunodeficiency unit were selected for participation. Patients were asked a series of open-ended questions to determine their knowledge and understanding of ADs. The constant comparative method was used to review the transcripts. It was found that only 31 per cent of patients had issued an AD, and 20% had learned of ADs for the first time during their hospitalization. Response analysis showed four phases of AD decision making: evaluation of illness, establishment of priorities, consideration of implications of the directives, and selection or rejection of directives. In conclusion, patients continue to have limited understanding of ADs and their implications. Continued investigation will elucidate the best strategies to educate patients about this topic.

[Cyst of the major omentum--laparoscopic diagnosis]

This report describes the case of a 22-year-old female patient with noncharacteristic complaints in the lower abdomen. Sonography revealed a large cyst close to the right adnexa, suggestive of adnexitis; however, laparoscopy, performed because of suspected adnexitis, revealed a cystic tumor connected to the omentum instead.

[Etiology and therapy of pneumothorax in AIDS patients]

Pneumothoraces in patients with AIDS are a rare, acute and severe complication. Between January 1989 and December 1991 3 patients with spontaneous pneumothorax were operated after a 2-week treatment with chest tube drainage only had failed. The average follow-up time after the operation was 7 months. There was no recurrence. Within the same 3 years 3 patients were treated in the Clinic for Internal Medicine by means of tube drainage only. Thus, only one case was successful. The average survival after receiving the tube was 3 weeks. Their death was not related on their pneumothorax. The mean age of the 6 patients was 34 years (23-49). In 5 patients the pneumothorax was associated with Pneumocystis carinii-pneumonia and in 3 of them also with prophylactic pentamidine aerosol therapy. A minimal invasive operation of operable AIDS-patients with pneumothorax shows good results, shortens the time of therapy and is possible despite the bad prognosis of the disease.

Benefits of an automated narcotic retrieval system

A comparison was made in effectiveness of lock and key and automated narcotics retrieval systems. Time required per narcotic averaged 137 seconds for the traditional mode and 48 seconds for the automated system. This resulted in a monthly savings of $594, along with general nurse satisfaction and a perception of increased security.

[Acute pancreatitis after local infusion of divalent cations]

The association of hypercalcemia and acute pancreatitis had been experimentally reproduced in cats by local infusions of the divalent cation calcium whereas the monovalent cation potassium did not induce any pancreatic pathology. The purpose of the present study was therefore to investigate the role of further divalent cations in order to determine the relevance of ion valency for pancreatitis induction. Anesthetized male SIV-rats received divalent cations, of which a role in the pancreas had already been reported in the literature, through retrograde infusions into the splenic artery at a dose of 0.6 mmol/kgh for 3 hours and at a flow of 0.5-1.0 ml/h. The pancreas was then removed for morphologic studies. In the animals treated with calcium and manganese, pancreas showed a hemorrhagic necrosis of the acinar lobuli with leucocytic infiltrates. The barium treated animals spontaneously died after 49 +/- 15 minutes and revealed acute pancreatitis in the perfused, but not in the residual pancreas. Zinc at the initial dose induced an immediate heparin-refractory blood-clotting with subsequent ischemic necrosis whereas a lower dosis (0.002 mmol/kgh) led to an acute pancreatitis as seen after calcium. The magnesium treated animals and the controls did not reveal any pathology. We conclude that some divalent cations may induce an acute pancreatitis, but that the induction is not dependent on the cation valency.

Ultrasound in blunt abdominal and thoracic trauma

Between July 1989 and June 1991, 312 patients with blunt thoracic or abdominal injuries were examined prospectively. Sonographic examination was performed by surgeons in the emergency room using a mobile ultrasound unit. In 113 (36.2%) cases pathologic findings were demonstrated sonographically. These included 47 cases of hemothorax, 11 pericardial effusions, 52 cases of intra-abdominal fluid, 24 lesions of intra-abdominal organs, and 10 cases of retroperitoneal hematoma. Physical examination findings were positive in 96 (30.8%), negative in 63 (20.2%), and equivocal in 153 (49.0%). Two hundred thirty-nine patients had between one and eight injuries in addition to the blunt abdominal or thoracic trauma. These patients had an average Injury Severity Score (ISS) of 19.9 (range, 1 to 75). The 73 patients with isolated blunt trauma of the thorax or abdomen had an ISS of 4.9 (range, 0-25). None of the 66 patients (21.2%) with positive clinical findings and negative sonographic examination results had to be operated on later in the course of treatment, while 5 (36%) of 14 patients (4.5%) with negative physical examination findings and positive sonographic findings had to undergo surgery. The sensitivity for the demonstration of intra-abdominal fluid and organ lesions was 98.1% and 41.4%, respectively. The overall sensitivity and specificity of the ultrasonic examination were 90.0% and 99.5%, respectively.

[Severe necrotizing fasciitis]

The pathophysiology of necrotizing fasciitis remains unclear in patients with no apparent immunologic disorders. Between 1987 and 1990 we treated six patients with necrotizing fascitis and septic-toxic multiple organ failure, three patients survived. The mean age was 38 years (25-62). In all patients the primary bacteriological examination revealed streptococcus. Between the first symptoms and an adequate therapy were 4 days in surviving patients and 7 days in patients who died. Four patients showed spread of the gangrene into the adjacent tissue: muscles (n = 3), bowel (n = 2), mediastinum (n = 1). Adequate débridement was not possible or not performed in patients with spread into the abdominal cavity or the mediastinum. These patients did not survive. The duration of intensive care treatment in surviving patients were 14 to 78 days. We conclude that survival of patients with severe necrotizing fasciitis is influenced by the delay before adequate treatment, the localisation of the gangrene and intensive care facilities.

[Perioperative complications in thyroid gland surgery]

The perioperative complication rate of 548 thyroidectomies in 536 patients was evaluated in a retrospective study. Local problems were present in 14% of the patients. Most frequent were paralysis of the recurrent nerve (5.0%) and hematoma or hemorrhage (4.3%). Systemic complications were seen in 2% of the patients, usually cardiopulmonary decompensation requiring intensive care treatment. The operative and hospitalisation mortality was 0%. Statistical evaluation revealed that patients older than 50 years and patients undergoing rethyroidectomy were at higher risk for local complications. Our results show, however, that thyroidectomy is a low risk operation at a teaching institution.

[30-months extracorporeal electrohydraulic shock-wave lithotripsy of gallstones using the MPL-9000 at the Zurich University Hospital]

The effect of extracoporeal shockwave lithotripsy (ESWL) in combination with oral chemolitholysis on gallstone clearance was tested in a prospective study. We used a non-waterbath lithotripter, and the patients were treated without general anesthesia or intravenous analgesia. They solely received oral or subcutaneous premedication. Within the 30 months study-period 78 patients were selected according to the "Munich-criteriae". At the end of the study period 33 patients were free of stones, 20 patients had residual fragments, and 25 patients stopped the therapy prior to complete stone clearance because of compliance (n = 11), or methodological (n = 14) problems. This includes 3 patients in whom the ESWL had to be discontinued because of pain. No severe complications were seen with the exception of one attack of acute pancreatitis, from which the patient recovered. The rate of stone clearance was analyzed using the life-table calculation according to KAPLAN-MEIER to weigh the follow-up time of each patient. At 12 months it revealed a stonefree rate of 70% in patients who did not discontinue the treatment because of methodological problems. The advantage of ESWL is the possibility to treat gallstones without general anesthesia or intravenous analgesia. However, the patient-population must be highly selected, and there is the risk of recurrence.

[Gallbladder morphology after extracorporeal shockwave lithotripsy of gallstones with the MPL-9000]

The effects of extracorporeal spark-gap shockwave lithotripsy (ESWL) on human gallbladder-morphology are barely known. We studied the gallbladders of nine patients cholecystectomized 5 to 166 days after ESWL. Patients were treated one to three times receiving a mean of 1928 +/- 693 shockwaves per treatment, with a total of 3375 +/- 1307 per patient. Control gallbladders were of randomly selected patients after plain cholecystectomy (age and sex-matched). There was no difference in pathomorphology of the two groups. No signs of trauma related damage (hemorrhage, necrosis, ulceration, scar, or hemosiderin deposits) other than from surgical manipulation were found. Predominant pathomorphological changes were signs of chronic cholecystitis due to gallstone disease. In conclusion, spark-gap ESWL did not induce deleterious morphological damage to the gallbladder, although large numbers of shock waves were applied.

[Bassini or Shouldice operation?]

Between October 1988 and March 1990 a controlled, prospective study was conducted comparing the operative methods of Bassini and Shouldice for hernia repair. On 100 patients (11 female, 89 male) the Shouldice-technique was used, on 55 patients (6 female, 49 male) the Bassini-technique. Most patients were operated under local anesthesia. No significant difference was noted between the two groups regarding the postoperative complication rate (hematoma, wound infection). However, patients had a shorter hospital stay after the Shouldice operation. Six patients (10.9%) had recurrent hernia after the Bassini procedure, one patient (1%) after the Shouldice procedure. An increased risk for recurrent disease was found in patients with the Bassini operation who already had recurrent hernia. Because of the significant shorter hospital stay and the significant lower incidence of recurrent hernia, we abandoned the operative method of Bassini in favour of the Shouldice procedure.

[Electron microscopy of the exocrine pancreas in experimental acute hypercalcemia]

Hypercalcemia has been associated with acute pancreatitis clinically and in the experimental animal. We studied the pancreatic ultrastructure in acute experimental hypercalcemia. Anesthetized cats (Pentobarbital, 0.55 mg/kg) received Ca++ (Calcium-Gluconate: 0.6 mmol/kgh; n = 4), K+ (KCl: 1.1 mmol/kgh; n = 4) or NaCl (0.9%; n = 4) locally through retrograde infusion into the splenic artery. Biopsies for electron microscopy (EM) were taken at three hours. Eight cats received intravenous Ca++ (0.6 mmol/kgh, 0.3 mmol/kgh after three hours) or NaCl (0.9%) for 12 hours. Biopsies were collected in two animals in three-hour intervals, and in all animals at twelve hours. After local calcium infusion necrotizing pancreatitis was seen macroscopically in the body of the pancreas. Biopsies for EM showed acinar cell necrosis, hydrops of nuclei and mitochondria and needle-like precipitates in the cytoplasma in the center of calcium perfusion. Biopsies taken from the peripheral region of the macroscopically altered tissue revealed desorganisation of the acinar polarisation and the endoplasmic reticulum, with zymogen granules appearing in the basolateral cell-portion. After intravenous calcium administration no macroscopical changes were seen. In EM acinar cells showed dilatation and proliferation of the golgi apparatus and increased number of condensing vacuoles indicating stimulation. Again, disorganisation of acinar cell polarisation was present. Control animals treated with K+ or NaCl showed normal pancreatic ultrastructure. The morphological changes after calcium infusion indicate direct damage to the acinar cell. Our results suggest that hypercalcemia induced pancreatitis could originate in the acinar cell.

[Experience with thoracoscopic pleurodesis in the treatment of idiopathic spontaneous pneumothorax]

Between January 1987 and December 1988 thoracoscopic pleurodesis has been used as a standard treatment for idiopathic spontaneous pneumothorax. Bullae were electrocoagulated, and visceral and parietal pleurae were cauterized. Chemical pleurodesis with 50% glucose-solution was added. 34 procedures were performed on 32 patients. The average hospital stay was 8 +/- 2 days. One patient suffered from postoperative Horner-syndrome. No other complications occurred. Patients were re-evaluated 11 +/- 8 months after the operation. Recurrence was found in four patients within 30 days. These patients underwent pleurectomy. Another patient had recurrence after two months. He was again and successfully treated by thoracoscopic pleurodesis. Our data show improvement of the results as compared with simple chemical pleurodesis.

[Typical nosocomial infection with an unusual cause: Hafnia alvei. Report of 2 cases and literature review]

The route of infection and the course of two typical nosocomial infections are described in two patients infected with a rare gram-negative bacterium. Both patients underwent cardiovascular surgery. They were placed close to each other in the intensive care unit for several days and suffered from pneumonia and from wound infection respectively. In both patients bacterial culture grew Hafnia alvei. Successful antibiotic treatment was achieved with Netilmicin and Imipenem. Urinary tract, respiratory tract and wound infections are the most frequent nosocomial infections according to the literature. Risk factors are duration of stay in the intensive care unit, shock, poor general condition and advanced age.

[The organization of gallstone lithotripsy using the MPL-9000 at the Zurich University Hospital, successes and failures. Initial results]

At Zurich fragmentation of gallstones is a joint venture between the Visceral Surgery Clinic, the Medical Clinic, Medical Policlinic, Radiodiagnostic Central Institute and Urologic Clinic. Lithotripsy is performed by a team from the Visceral Surgery Clinic with apparatus placed at their disposal by the Urologic Clinic. Indications for lithotripsy include symptomatic cholecystolithiasis, functioning gallbladder, and up to 3 gallstones of at least 10 mm and at most 30 mm diameter. Bile duct stones, acute cholecystitis, coagulopathy, pregnancy, aortic aneurysm and pacemakers are exclusion criteria. Patients spend two days in hospital, lithotripsy is performed without anesthesia, and outpatient follow-up is performed 1, 3, 6 and 12 months afterwards. Our experiences show that lithotripsy is more difficult and more treatments are needed if multiple gallstones are present. We had to perform cholecystectomy in 6 of a total 48 patients, mainly because of therapy resistant biliary pain due to stone fragments. The intraoperative findings did not correspond to the ultrasonic examination before lithotripsy in two of the patients who underwent cholecystectomy. Histologic examination of the six gallbladders in the surgical cases showed no abnormality. After an average treatment duration of 209 days, 9 of 48 patients are stone-free, 15 patients show improvement, in 14 patients no distinct reduction of fragments could yet be shown in recent follow-ups and 4 patients have not yet been reached for follow-up. Of the 230 patients examined lithotripsy was indicated only in 48 (21%) cases.

[Organization of gallbladder lithotripsy with the MPL-9000 at the Zurich university hospital. Initial results]

Gallstone shock wave therapy at the University Hospital of Zurich is a joint venture between the Medical Clinic, Medical Policlinic and Surgical Clinic. Patients with symptomatic cholecystolithiasis willing to submit themselves to a long period of treatment, were accepted for ESWL, should no contraindications be present. From October 1988 through May 1989 we treated 48 patients. In approximately two thirds of our patients we were successful with one ESWL alone, in one third 2 sessions and in two patients even 3 sessions were needed. In 42 patients course after therapy was as planned. Six had to be cholecystectomized later on. Best results were achieved in patients with single gallstones. In 2 of 5 cases there was disagreement between the number of gallstones found sonographically and the intraoperative findings. Histologic examination of gallbladders after ESWL showed no pathologic changes.

[Rate of perioperative complications of thyroid surgery]

Mortality and complication rate of thyroid surgery was evaluated between 1980 and 1987. Patients undergoing thyroidectomy during parathyroidectomy, tracheotomy or tumor operation in the anterior mediastinum were excluded. 548 thyroidectomies were performed in 536 patients. There were no mortalities. The incidence of local complications was 16% with paralysis of the recurrent nerve being the most frequent (6.2%). Other complications were hematoma or hemorrhage (4.9%), hypocalcemia (2.1%), allergic skin reaction (1.3%), or wound infection (0.7%). 2.2% of the patients needed reoperation because of false negative interpretation of a frozen section, or carcinoma in final histology. Systemic complications were found in 13 patients (2%), 6 of whom required intensive care treatment. Statistical analysis revealed that patients undergoing total thyroidectomy or re-thyroidectomy, and patients older than 50 years are at higher risk for local complications.

[Intestinal necroses in severely injured patients without abdominal trauma]

Bowel necrosis in the critical trauma patient without abdominal involvement or preexisting vascular disease is a known but rare complication. During 1977-1986 we observed 31 cases in 2530 patients. Symptoms were unspecific, and since most of the patients were artificially ventilated, pain and tenderness were of little diagnostic value. Twenty-three patients presented with paralytic ileus, fifteen with diarrhea, and four with melena. In eleven patients diagnosis was made clinically, and in twenty patients at autopsy. Twenty-three patients died from septic shock, six from cerebral complications, and one from myocardial infarction. Risk factors for bowel necrosis were fluid restriction, hypotension, hypoxemia, venous congestion, vasoconstrictive drugs, paralytic ileus, and constipation.

Incidence and treatment of candida esophagitis in patients undergoing renal transplantation. Data from the Minnesota prospective randomized trial of cyclosporine versus antilymphocyte globulin-azathioprine

Of 224 consecutive renal transplant patients in a prospective, randomized immunosuppressive trial, candida esophagitis developed in 5 despite nystatin prophylaxis. No differences were noted between cyclosporine and antilymphocyte globulin-azathioprine immunosuppressive treatment. All patients were diabetic, and four were recipients of cadaver kidneys. Candida esophagitis occurred within 6 months after transplantation, and only one patient had recurrence. All patients responded to treatment consisting of 2 to 6 days of intravenous amphotericin B (0.2 to 2 mg/kg total dose). The prevalence of candida esophagitis was not related to rejection episodes. Three of five patients eventually died, one 2 weeks after resolution of candida esophagitis from a hypoglycemic episode, one from acute exacerbation of pulmonary failure and relapsing pancreatitis in association with candida esophagitis and therapy-resistant candidemia, and one 17 months after candida esophagitis from pulmonary edema. Our findings show that candida esophagitis by itself is an easily managed complication, but is also a sign of potentially increased morbidity in these patients.

Blood units for patients with irregular blood group antibodies: frequency and supply

Blood banks face significant problems supplying blood units compatible with erythrocyte antigens other than ABO and rhesus D. In this study the number of such units was evaluated between 1973 and 1982, and it was found that 1.5% of the total number of blood units were compatible with other antigens than ABO and rhesus D. Based on data of the number of units requested for each such antigen and the frequency of the antigen in the European population, a logistical system providing sufficient numbers of 'antibody-compatible' blood units is proposed.

Mechanism for the interaction of thiols with methylcobalamin

The reaction between methylcobalamin and ethane-thiol sulfonic acid (Co-enzyme M) has been studied under aerobic conditions. For this reaction evidence is presented for a catalytic cycle which promotes homolytic cleavage of the Cobalt-carbon sigma-bond to give Cob(II)alamin (B12-r) and methylcoenzyme M as the products. This reaction is especially pertinent to our understanding of the mechanism of methane-biosynthesis. In addition, we have used 220 MHZ 1H NMR and 13C NMR to show that thiols do not react with methylcorrinoids by displacing the base trans-axial to the cobalt-carbon bond. This NMR study is especially important since the co-ordination of thiols to cobalt has previously been reported to occur by a number of research groups including our own.

Effect of poly I:C-induced interferon on herpes virus hominis infection in vitro and in vivo

In this study the effect of poly I : C-induced interferon on Herpesvirus hominis (HVH) infection in vitro and in vivo was investigated.

The in vitro results revealed a significant effect of interferon on infections of HVH strains of different origin in mouse embryonic cells.

The in vivo experiments performed in the HVH-mouse system indicate that the effective induction of interferon in an aminal increases its resistance to subsequent infection with HVH.