Irritable bowel syndrome and recurrent abdominal pain. A comparative review

Clinical findings on irritable bowel syndrome in adults and recurrent abdominal pain in children are reviewed to determine if what is known about each disorder can illuminate our understanding of the other. The evidence reveals striking similarities between the disorders in prevalence, course, medical and psychiatric comorbidity, family medical and psychiatric history, and association with life events. Continuity between the two disorders is also suggested by the results of follow-up and follow-back studies. The review shows the importance of a developmental perspective for understanding functional bowel disorders in adults and points to areas where further research would be useful.

[Ultrasonography contrast media Levovist and power Doppler in the study of the breast. Methodology, vascular morphology and automatic enhancement quantification with wash-in and wash-out curves]

PURPOSE

To define the technique for contrast-enhanced power Doppler US studies of breast lesions and to identify possible clinical applications.

MATERIAL AND METHODS

We studied 51 breast lesions detected at mammography and confirmed at cytology and/or surgical biopsy; 15 were benign lesions and 36 carcinomas, namely 14 T1ab, 29 T1c and 8 T2. We found 14 masses with regular margins, 28 with irregular margins, 1 asymmetric density, 2 architectural distortions and 6 clustered calcifications. US studies were performed with an AU5 Harmonic unit (Esaote Biomedica, Genoa, Italy) equipped with a software for online image storage, analysis and automatic quantification of US signal intensity changes after contrast agent injection, namely wash-in and wash-out contrast enhancement curves. The echocontrast agent Levovist (Schering AG, Berlin, Germany), 4.0 g preparation, was administered by i.v. injection (cubital vein) in two times at a concentration of 400 mg/mL. The first 4 mL of Levovist suspension were injected as a bolus at approximately .5 mL/s to evaluate lesion vascularization and choose the best scanning plane for wash-in and wash-out quantification. The remaining 6 mL of Levovist suspension were injected at approximately 1.0 mL/s and dedicated to wash-in and wash-out recording.

RESULTS

The region of interest could not be identified in 2 of 6 calcifications. After Levovist administration, signal enhancement was seen in 36 lesions. Nonsignificant curves were obtained in 7 fibroadenomas, 1 fibrocystic mastopathy and 5 carcinomas. Pathology diagnosed an in situ component around the lesion core (true positives) in 12 carcinomas with perilesional vessels and also 3 more carcinomas with perilesional foci in situ missed at contrast-enhanced US (false negatives). The wash-in/wash-out curves of 30 carcinomas differed from those of the 6 fibroadenomas, in that the former had faster wash-in and an earlier enhancement peak, as well as longer enhancement than the latter. Moreover, fibroadenoma curves are regularly increasing, with moderate variations. As for wash-out, carcinomas exhibited three main patterns, namely a monophasic, a polyphasic and a plateau pattern.

DISCUSSION

The pattern of enhancement curves in fibroadenomas is related to straight and regular vessels, while arteriovenous shunts in carcinomas cause early signal intensity peaks. Wash-out is longer in carcinomas than in fibroadenomas because the former present anarchic and tortuous vessels with slow flows.

CONCLUSIONS

Levovist enhanced US is a complementary test to study known breast lesions which permits the differential diagnosis of carcinomas and fibroadenomas. Our results justify a larger clinical trial to assess the role of this technique for diagnosis, prognosis and staging purposes.

Colonization with broad-spectrum cephalosporin-resistant gram-negative bacilli in intensive care units during a nonoutbreak period: prevalence, risk factors, and rate of infection

OBJECTIVE

To define the epidemiology of broad-spectrum cephalosporin-resistant gram-negative bacilli in intensive care units (ICUs) during a nonoutbreak period, including the prevalence, the risk factors for colonization, the frequency of acquisition, and the rate of infection.

DESIGN

Prospective cohort study.

SETTING

Tertiary care hospital.

PATIENTS

Consecutive patients admitted to two surgical ICUs.

MAIN OUTCOME MEASUREMENTS

Serial patient surveillance cultures screened for ceftazidime (CAZ) resistance, antibiotic and hospital exposure, and infections.

RESULTS

Of the 333 patients enrolled, 60 (18%) were colonized with CAZ-resistant gram-negative bacilli (CAZ-RGN) at admission. Clinical cultures detected CAZ-RGN in only 5% (3/60) of these patients. By using logistic regression, CAZ-RGN colonization was associated with duration of exposure to cefazolin (odds ratio, 10.3; p < or = .006) and to broad-spectrum cephalosporins/penicillins (odds ratio, 2; p < or = .03), Acute Physiology and Chronic Health Evaluation III score (odds ratio, 1.2; p < or = .008), and previous hospitalization (odds ratio, 3.1; p < or = .006). Of the 100 patients who remained in the surgical ICU for > or = 3 days, 26% acquired a CAZ-RGN. Of the 14 infections caused by CAZ-RGN, 11 (79%) were attributable to the same species present in surveillance cultures at admission to the surgical ICU.

CONCLUSIONS

Colonization with CAZ-RGN was common and was usually not recognized by clinical cultures. Most patients colonized or infected with CAZ-RGN had positive surveillance cultures at the time of admission to the surgical ICU, suggesting that acquisition frequently occurred in other wards and institutions. Patients exposed to first-generation cephalosporins, as well as broad-spectrum cephalosporins/penicillins, were at high risk of colonization with CAZ-RGN. Empirical treatment of nosocomial gram-negative infections with broad-spectrum cephalosporins, especially in the critically ill patient, should be reconsidered.

Depression in pediatric chronic illness. A diathesis-stress model

Depression in pediatric chronic illness has been receiving increasing attention in recent years. Studies to date have typically focused on characteristics of illness as the major determinants of the development of depression, but characteristics of the child have received less attention. This review suggests that a diathesis-stress model can be a fruitful heuristic that would incorporate illness characteristics and attributes of the child and environmental effects in an overall framework to guide future research and treatment.

The Limerick Leg-Ulcer Project: early results

Nurse led clinics in joint hospital and community settings are now being advocated as the most effective and economic way of dealing with leg ulcers. However, little information exists on the profile and outcome of patients with venous ulcers treated either in the community or in the hospital setting. Over a 2 yr period we assessed 134 patients with leg ulcers of whom 122 were deemed suitable for compression bandaging therapy. Thirty-four patients (28 per cent) were treated by the newly developed community service and 88 (72 per cent) were treated at the hospital clinic. Our overall healing rate for venous ulcers was 50 per cent @ 40 weeks. This probably reflects the long duration (48 per cent > 2 yr) and large size (0.5-600 cm2) of ulcer prior to treatment. There were no differences in outcome between hospital (50 per cent @ 40 weeks) and community (35 per cent @ 40 weeks) based treatment (p > 0.05). We conclude that most venous ulcers can be effectively treated in the community and resources should be provided to achieve this goal.

A group treatment approach to failure to toilet train: the case of Max

Toilet training is a major developmental milestone for children and parents. Accurate statistics on the prevalence of toilet-training failure do not exist; however, it is estimated that approximately 4% of 4-year-olds are not bowel trained. A number of biopsychosocial and developmental factors can interfere with toilet training. Frequently, a cycle of withholding and constipation with painful bowel movements and/or overflow incontinence ensues. A case study of a 4-year-old boy with encopresis and pervasive developmental disorder will highlight an interdisciplinary team's approach to helping children (4-6 years old) toilet train. Along with individual patient care management, parents and children attended (separately) a six-session medical and psychoeducational group called "Toilet School." This group model employs the principles of behavior modification, the concepts of children's preoperational thinking, and a philosophy of care that values collaborative relationships between caregivers and families.

Effects of human recombinant growth hormone (rhGH) on inflammatory responses in patients undergoing abdominal aortic aneurysm repair

BACKGROUND

Human recombinant growth hormone (rhGH) has been shown to increase skeletal muscle protein synthesis and improve nitrogen balance in critically ill patients and those undergoing surgery. rhGH effects on hepatic protein turnover in critically ill patients are less clearly understood.

OBJECTIVE

To examine rhGH effects on hepatic acute phase protein responses and inflammatory cytokine release in patients undergoing major surgery.

DESIGN

Prospective double blind randomised trial.

SETTING

Tertiary referral university teaching hospital.

PATIENTS

Patients undergoing elective abdominal aortic aneurysm repair.

INTERVENTION

Patients received rhGH (Genotropin, 0.3 IU/kg per day, n = 8) or placebo (n = 10) for 6 days prior to surgery.

RESULTS

Blood levels of growth hormone (GH) and insulin-like growth factor (IGF-1) were measured following rhGH treatment and C-reactive protein (CRP), serum amyloid A (SAA) and the cytokines interleukin-6 (IL-6) and the IL-1 receptor antagonist (IL-1ra) were measured for up to 24 h following surgery. Significant increases in plasma rhGH (0.84 +/- 0.3, mean (sem) versus 52 +/- 20 mU/l, p < 0.0008) and IGF-1 levels (119 +/- 13 versus 644 +/- 110 ng/ml, p < 0.0001) were seen prior to surgery following rhGH administration. No differences in acute phase protein or cytokine levels were seen following surgery in patients receiving rhGH.

CONCLUSIONS

These results indicate that pre-operative administration of rhGH does not alter acute phase protein or inflammatory cytokine release in response to major surgery.

The effects of 13-cis retinoic acid and interferon-alpha in chronic myelogenous leukemia cells in vivo in patients

The effects of the administration of a 3-day course of 13-cis retinoic acid in combination with interferon a [RA/IFN] on the leukemia cells was measured in vivo in 43 patients with chronic myelogenous leukemia. The administration of RA/IFN was associated with a significant fall in the white blood cell count of patients with chronic-phase disease and with a fall in the percentage S-phase cells in CML patients regardless of the stage of their leukemia. In two thirds of the patients studied the administration of RA/IFN was also associated with an increase in marrow apoptosis. The cytokine combination also suppressed bcl-2 and myc expression in a minority of patients and such expression appears to be associated with response to a treatment regimen which includes RA/IFN. These studies are the first to directly assess the effects of the combination of RA/IFN on chronic myelogenous leukemia cells in vivo in patients. These effects, if seen in other malignant diseases, could account for the therapeutic benefit which has been associated with the administration of this combination of biological agents to patients with malignant disease.

The economic impact on families of children's participation in junior sport

The study investigated the socio-economic consequences for families of participation in junior sport. Two hundred and twenty families in Queensland and Victoria were surveyed from the sports of cricket, Australian football, gymnastics, hockey, netball and tennis and twenty seven of these interviewed. The study showed that parents make a substantial contribution in terms of financial support to their children's participation in junior sport. Each of the sports mode different financial demands on families depending on the yearly cycle of training and competition, distance from facilities and coaching, costs associated with coaching, equipment and uniforms, and representative level. It is concluded that family income and structure are the key factors in determining the likelihood of a child's involvement in junior sport, and that for many Australian children, financial factors may be barriers to their participation in junior sport.

Safety and immunogenicity of a bivalent Haemophilus influenzae type b/hepatitis B vaccine in healthy infants. Hib-HB Vaccine Study Group

OBJECTIVE

To assess the safety, tolerability and immunogenicity of COMVAX, a liquid, bivalent Haemophilus influenzae type b-hepatitis B vaccine, containing the polyribosylribitol phosphate (PRP)-Neisseria meningitidis outer membrane protein complex conjugate used in the Hib vaccine, PedvaxHIB, and the yeast-derived hepatitis B surface antigen (HBsAg) used in the HB vaccine, RECOMBIVAX HB.

DESIGN

Eight hundred eighty-two healthy infants, approximately 2 months of age, were enrolled in an open, multicenter (n = 11) clinical trial and randomized to receive either COMVAX (7.5 micrograms of PRP/5 micrograms of HBsAg in 0.5 ml) or concurrent injections of the liquid formulation of PedvaxHIB (P) (7.5 micrograms of PRP in 0.5 ml) and RECOMBIVAX HB (R) (5 micrograms of HBsAg in 0.5 ml) at 2, 4 and 12 or 15 months of age. Safety and tolerability were monitored after each injection. The serum concentrations of anti-PRP and anti-HBs were determined at the time of each vaccination, 2 months after the second vaccination and 1 month after the third vaccination.

RESULTS

COMVAX was well-tolerated and proved to be immunologically comparable with a series of concomitant P+R injections. There were no serious adverse experiences attributable to the study vaccines. The most commonly reported nonserious adverse experiences were all events prelisted on diary cards given to parents. These included generally mild and transient signs of inflammation at the injection site (pain/ soreness, erythema, swelling/induration), somnolence and irritability. Because children are at peak risk of invasive Hib disease during the first year of life, 6 months of age (2 months after the second dose of vaccine) was designated the time of primary interest with regard to the development of anti-PRP. At that time 94.8% of the infants given COMVAX had > 0.15 microgram/ml of anti-PRP and 72.4% had > 1.0 microgram/ ml, with a geometric mean concentration (GMC) of 2.5 micrograms/ml, compared with 95.2%, 76.3% and 2.8 micrograms/ml, respectively, in recipients of P+R. The third injection given at 12 or 15 months of age induced a secondary rise in antibody. The proportions with > 0.15 microgram/ml and > 1.0 microgram/ml of anti-PRP increased to 99.3 and 92.6%, respectively, and the GMC rose to 9.5 micrograms/ml among COMVAX recipients, compared with 98.9%, 92.3% and 10.2 micrograms/ml in children given concurrent injections of P+R. In contrast to Hib few infants in countries with low endemicity of HBV infection are at near term risk of exposure to virus. Consequently the anti-HBs response after the last dose of vaccine was designated the outcome of primary interest. At 13 to 16 months of age (1 month after the third dose of vaccine) 98.4% of children given COMVAX had a protective anti-HBs concentration of > or = 10 mIU/ml with a GMC of 4468 mIU/ml, compared with 100% and a GMC of 6944 mIU/ml among children given P+R.

CONCLUSIONS

COMVAX is well-tolerated by healthy infants and can induce immunity against invasive Hib disease and HBV infection using only three injections compared with six injections if separate courses of monovalent PedvaxHIB and RECOMBIVAX HB are given.

Bcl-2 and c-myc expression, cell cycle kinetics and apoptosis during the progression of chronic myelogenous leukemia from diagnosis to blastic phase

Chronic myelogenous leukemia (CML) has a progressive course but little is known about the biologic characteristics of disease progression. This study was designed to assess the changes in cell proliferative characteristics, apoptosis, the expression of the bcl-2 and c-myc genes between the time of initial diagnosis and entrance into the blastic phase of the disease. We observed that the rate of cell proliferation decreased and the cell death rate did not significantly change as the disease accelerated. The level of bcl-2 expression was significantly higher in accelerated/blastic phase cells than in the chronic phase cells in the population as a whole, however, the bcl-2 expression level did not change in blast cell subpopulation. c-myc Expression was significantly higher in the blast cell subpopulation of accelerated/blastic phase than in that of earlier phases of the disease. In conclusion, the characteristics of CML cells, namely proliferation rate, c-myc and bcl-2 change during the course of the disease. It is possible that the change in c-myc expression plays a causative role in evolution of the blastic phase from the chronic phase.

Nitric oxide attenuates interleukin 2-induced lung injury

BACKGROUND

The pathogenesis of interleukin (IL) 2-induced vascular leak syndrome may be related to neutrophil-mediated endothelial injury. Nitric oxide inhibits neutrophil superoxide anion synthesis and adherence to endothelial cells. The role of systemic nitric oxide in preventing IL-2-induced lung injury was studied in an experimental model.

METHODS

Sprague-Dawley rats (seven per group) were randomized to control, IL-2 treatment (1 x 10(6) units), and IL-2 with sodium nitroprusside 0.2 mg/kg. Lung injury was measured by estimation of extravascular lung water (wet:dry weight) and bronchoalveolar lavage (BAL) protein concentration, and by histological findings. Neutrophil infiltration was evaluated by measuring myeloperoxidase activity and BAL neutrophil concentration.

RESULTS

IL-2 produced significant lung damage characterized by leucocyte sequestration (increased myeloperoxidase and BAL neutrophil concentrations), pulmonary congestion and microvascular protein leakage (increased wet:dry weight ratio and BAL protein concentration). This injury was reduced significantly by the addition of sodium nitroprusside, the nitric oxide donor.

CONCLUSION

Nitric oxide reduces IL-2-induced lung injury.

Immunological and physiological responses to aortic surgery: effect of reperfusion on neutrophil and monocyte activation and pulmonary function

BACKGROUND

The aims of this study were to evaluate the effects of aortic clamping and unclamping on neutrophil and monocyte activation and release of plasma mediators in 20 patients undergoing elective aortic aneurysm surgery, and to correlate these findings with pulmonary haemodynamics and gas exchange.

METHODS

Simultaneous arterial and mixed venous samples were obtained during and after aortic clamping and unclamping.

RESULTS

Neutrophil respiratory burst activity in mixed venous samples increased significantly during the period of aortic clamping. An initial increase in neutrophil CD11b expression in venous blood 5 min after clamp removal was followed by a significant decrease in level of expression. Plasma tumour necrosis factor levels increased at the end of the cross-clamp period and reached a maximum 60 min following reperfusion. There was a significant and sustained rise in plasma thromboxane B2 levels following clamp removal. This increase correlated with the development of increased pulmonary vascular resistance.

CONCLUSION

This study confirms the central role played by activated neutrophils in the early stages of reperfusion injury and also suggests a role for plasma mediators in mediating cardiopulmonary dysfunction during major vascular surgery.

[Spermatic phlebography and sclerotherapy of the male varicocele]

Phlebographic sclerotherapy and embolization are better methods, from the biological and cost-effectiveness viewpoints, to treat male varicocele than conventional surgery. On the other hand, positive technical results are not always obtained and the rates of relapses and recurrences are high. A retrospective study was carried out on 70 (of 81) sclerotherapies performed in the Radiology Department of S. Anna Hospital, Turin, from 1993 to September, 1995. The results confirmed the feasibility of this treatment in a nonangiographic department, with technical success rates increasing with growing operators' experience (70% success rate in 1993, vs. more than 95% in 1994-95). Recurrence rate was 4.9% and the rate of limited persistence was 7.3% at clinical and Doppler follow-up ranging 6-24 months (mean: 10.2 months). Both rates appeared to be related to varicocele initial size, increasing progressively from grade I to grade III. Therefore, such new and expensive techniques as balloon or spiral embolization are justified only in the most severe cases. The follow-up showed improved or normalized sperm exams in 70.4% of treated and followed-up patients, with 5 full-term pregnancies. To conclude, sclerotherapy and embolization of the spermatic vein are very good tools to treat male varicocele with subfertility.

Antibody-directed enzyme prodrug therapy (ADEPT)

A conjugate of the bacterial enzyme carboxypeptidase G2 and the F(ab)(2) fragment of the anti-CEA monoclonal antibody A5B7 was directed in vitro at the human colon tumour cell line LS174T and the human non-small cell lung line COR-L23. Indirect immunofluorescence microscopy was used to show that the conjugate bound to LS174T cells but not to COR-L23. The cytotoxicity generated by addition of a phenol mustard prodrug to each cell line after pre-incubation with conjugate was found to be significantly greater for LS174T cells (IC50=0.24 mu M) than COR-L23 cells (IC50=108 mu M). However, for a 1:1 mixture of these cells an IC50, of 3.4 mu M was obtained. These data show that phenol mustard released by a localised conjugate can exert a bystander effect on neighbouring cells to which the conjugate does not bind.

Glyceryl trinitrate prevents neutrophil activation but not thromboxane release following ischaemia-reperfusion injury

The aim of this study was to determine whether glyceryl trinitrate (GTN) has a protective effect on neutrophil-mediated lung injury in a model of aortic occlusion (30 min) and reperfusion (120 min). Sprague-Dawley rats were randomized into control (n = 11), ischaemia-reperfusion (IR) (n = 12), and IR treated with GTN (2 micrograms kg-1 min-1) during reperfusion (n = 10). Myeloperoxidase (MPO) activity measured pulmonary neutrophil influx. Pulmonary endothelial permeability was measured by wet:dry weight ratio, bronchoalveolar lavage (BAL) protein and neutrophil counts. Neutrophil superoxide release was measured by flow cytometry in a further IR versus GTN experiment (n = 6 in each group). The significant increase in MPO activity produced by IR to a level of 7.99 units g-1 was prevented by GTN which reduced the level to 4.73 units g-1. The increase in pulmonary microvascular leakage after reperfusion was also prevented by GTN: BAL protein without GTN was 992 micrograms ml-1 and with GTN 579 micrograms ml-1; BAL neutrophil count without GTN was 3219 cells mm-3 and with GTN 820 cells mm-3; the wet:dry lung weight ratio without GTN was 3.8 and with GTN 3.3. Neutrophil superoxide release increased significantly after 40 min of reperfusion in the untreated IR group (P < 0.05). This increase was prevented in the GTN-treated group. GTN administration had no effect on plasma thromboxane production during revascularization. These data suggest that GTN administration during the reperfusion phase has the potential to decrease pulmonary microvascular injury.

Accuracy of immunohistochemistry and flow cytometry in estimating the proportion of leukemic cells in S phase in chronic myeloid leukemia patients

We compared the proportion of S phase cells in bone marrow and peripheral blood samples obtained from 17 patients with chronic myeloid leukemia (CML). Before sampling all patients received a one hour i.v. infusion of iododeoxyuridine (IdUrd). The proportion of S phase cells was studied by immunohistochemistry (IHC) in bone marrow biopsies, and by flow cytometry (FCM) in bone marrow aspirates and peripheral blood samples. The IdUrd labelling index (LI) in bone marrow biopsy sections (27.5 +/- 1.8%) was significantly higher than the proportion of IdUrd labelled cells in bone marrow aspirate (15.1 +/- 2.0%). The percentage of S phase cells in peripheral blood was approximately the same as that in the aspirate (12.4 +/- 1.3%) and was correlated with that of bone marrow aspirate indicating a high degree of the aspirate dilution by peripheral blood. It is likely that the differences in % S phase cells in the aspirate and the biopsy result from this dilution. Estimates of the % S phase cells in the peripheral blood study by IHC and FCM were essentially the same. Samples labelled for one hour in vitro resulted in 1.5 fold higher LI than the same samples labelled in vivo. We conclude that estimates of the 8% S phase cells in the bone marrow of patients with CML should be made by infusing patients with IdUrd or BrdUrd with immunohistochemical evaluation of a marrow biopsy. Additionally in vitro labelling is not reflective of the percent S phase cells in vivo in patients.

[Quality and homogeneity monitoring of radiologists in the Turin mammographic screening. Comparison of the pilot phase results]

The Turin mammographic screening program was designed to be carried out in several independent screening centers because of the large proportion of population involved (76,000 women aged 50 to 59 years). The first center began working in 1992 and the second center was opened in 1995. The latter center carried out an early pilot study in which 1024 women were examined to assess the homogeneity and the quality of the results. The results were then compared with European quality standards and with the results of both the pilot and the active screening periods in the first center. The results from the second center were very good as far as detection rate is concerned (7.8/1000-2.9/1000 in carcinoma < or = 1 cm). This rate is higher than the so-called "desirable" European standard. Recall rate and benign/malignant biopsy ratio were higher than the so-called "fair" European standard (recall rate: 7.1%; B/M biopsy ratio: 0.62). These results are slightly superior to those of the pilot period in the first center and slightly inferior to the results of active screening in the same center. The improvement relative to the pilot period in the first center (1991) is probably related to technical progress, such as the introduction of the double mammographic projection. The difference relative to the results from the active screening period in the first center (1992-1994) reflects different specific experience. Even though pilot periods have no statistical significance, they can be used for comparison, and in our experience they have proved, with positive results, the quality of the mammographic screening program provided to the Turin population.

Systemic cytokine administration alters the histology of the eruption of lymphocyte recovery

The eruption of lymphocyte recovery occurs after marrow ablative antineoplastic chemotherapy, with the earliest reappearance of lymphocytes in the peripheral circulation. The typical histopathologic findings are not specific, consisting of a perivascular lymphocytic infiltrate in the upper dermis with mild overlying epidermal changes. Since the initial report, 21 additional biopsy specimens from eruptions of lymphocyte recovery were obtained at our institution. Of these specimens, 18 displayed the expected findings while 3 specimens contained a relatively heavy lymphocytic infiltrate with nuclear pleomorphism and hyperchromasia. The majority of lymphocytes from the heavily inflamed tissues expressed CD3 and CD4; rare CD8+ cells were observed. The cells with large irregular nuclear contours displayed an "activated" phenotype, consisting of CD30, HLA-DR, and CD25, accounting for roughly 50% of the total infiltrate. The three patients from whom these specimens were obtained had received human recombinant cytokines in pharmacologic doses (2 granulocyte-macrophage colony stimulating factor, 1 interleukin-3). Three patients in this series also received human recombinant cytokines, but developed eruptions with the typical scant infiltrate of small lymphocytes. These findings extend the histologic spectrum of the eruption of lymphocyte recovery and suggest that the administration of human recombinant cytokines prior to marrow recovery may alter the appearance and phenotype of lymphocytes migrating into the skin.

Higher ploidy in Saccharomyces cerevisiae supports enhanced hepatitis B virus S cloned gene expression at the pilot scale

The effect of host strain ploidy on the production of hepatitis B surface antigen (HBsAg) in Saccharomyces cerevisiae was evaluated at the pilot scale (75 L). We found that the accumulation of HBsAg normalized to cell protein was 2-fold higher for the diploid strain compared to its isogenic haploid. No detectable differences in many fermentation parameters were observed (e.g., rate of fermentation, growth rate, final cell yield). However, the enhancement of productivity in the diploid strain appeared to be associated with a slower rate of plasmid shedding (2 microns element) and, thus, a higher average copy number (2-fold at stationary phase) compared to those of the haploid strain.