Effect of cetrimide and ascorbic acid on in vitro human skin permeation of haloperidol

Permeation of haloperidol through the human skin in vitro was studied with two enhancers, cetrimide and ascorbic acid, at various concentrations. Amber glass Franz-type diffusion cells were used for the permeation studies and haloperidol was made soluble in aqueous solution with the aid of lactic acid. Donor solutions were prepared by adding excess of haloperidol to 0.03% (v/v) lactic acid solution with or without enhancers at concentrations 0.1, 0.3 and 0.6% (w/v) and stirred for 36 h at 32 degrees C before filtering. Ascorbic acid gradually increased the solubility of the haloperidol from that of the control where as cetrimide did not show any effect. Cetrimide concentration dependent increase in the permeability coefficient of haloperidol was observed. Mechanism of enhancement by cetrimide was probed with the diffusion profile kinetics and Fourier transform infrared (FT-IR) spectroscopy. Cetrimide was found to increase the thermodynamic activity of the drug in the skin. IR spectra of the stratum corneum treated with cetrimide showed time-dependent decrease in the intensity of the spectrum and dose-dependent decrease of lipid band but no change in the protein conformation. Cetrimide appears to interact with both the dermal keratin and lipids and this interaction was found to be irreversible. Ascorbic acid although increased the flux of haloperidol to the same extent at all concentrations from that of the control, decreased the permeability coefficient and enhancer index in a concentration dependent manner and this is due to the increased solubility of the drug in the vehicle. Both the enhancers did not change the lag time from that of the control.

Protective effects of curcumin against oxidative damage on skin cells in vitro: its implication for wound healing

BACKGROUND

Curcumin, isolated from turmeric, has been known to possess many pharmacologic properties. It has been proven to exhibit remarkable anticarcinogenic, anti-inflammatory, and antioxidant properties. Turmeric curcumin may be a good potential agent for wound healing.

METHODS

To further understand its therapeutic mechanisms on wound healing, the antioxidant effects of curcumin on hydrogen peroxide (H2O2) and hypoxanthine-xanthine oxidase induced damage to cultured human keratinocytes and fibroblasts were investigated. Cell viability was assessed by colorimetric assay and quantification of lactate dehydrogenase release.

RESULTS

Exposure of human keratinocytes to curcumin at 10 microg/mL showed significant protective effect against hydrogen peroxide. Interestingly, exposure of human dermal fibroblasts to curcumin at 2.5 microg/mL showed significant protective effects against hydrogen peroxide. No protective effects of curcumin on either fibroblasts or keratinocytes against hypoxanthine-xanthine oxidase induced damage were found in our present studies.

CONCLUSION

The findings indicate that curcumin indeed possessed powerful inhibition against hydrogen peroxide damage in human keratinocytes and fibroblasts.

Characterization of additional genetic events in childhood acute lymphoblastic leukemia with TEL/AML1 gene fusion: a molecular cytogenetics study

TEL/AML1 gene fusion that results from a cryptic t(12;21) is the most common genetic aberration in childhood B-lineage acute lymphoblastic leukemia (ALL). While the translocation may initiate the leukemic process, critical secondary genetic events are currently believed to be pivotal for leukemogenesis. We investigated 12 cases of childhood ALL with TEL/AML1 gene fusion by fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) and documented additional or secondary genetic changes in seven patients (58%). Three patients showed extra copies of chromosome 21 including a case in which the trisomy 21 (+21) clone was distinct from the one harboring TEL/AML1 gene fusion. Interestingly, one patient without +21 showed amplification of the AML1 gene on chromosome 21q, supporting the contention that AML1 amplification may be an important additional genetic event. Gene expression study by semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) in two of these four patients showed an increase in AML1 transcripts that paralleled the increase in gene copy number. Deletion of the normal TEL allele was detected in two patients, with one of them showing loss of chromosome 12 together with duplication of the der(12)t(12;21). Finally, one patient showed duplication of the fusion signal. Our findings confirm that additional or secondary genetic changes including AML1 amplification are commonly encountered in childhood ALL with TEL/AML1 gene fusion, which are envisaged to play significant roles in disease progression.

Folate receptor-alpha is a cofactor for cellular entry by Marburg and Ebola viruses

Human infections by Marburg (MBG) and Ebola (EBO) viruses result in lethal hemorrhagic fever. To identify cellular entry factors employed by MBG virus, noninfectible cells transduced with an expression library were challenged with a selectable pseudotype virus packaged by MBG glycoproteins (GP). A cDNA encoding the folate receptor-alpha (FR-alpha) was recovered from cells exhibiting reconstitution of viral entry. A FR-alpha cDNA was recovered in a similar strategy employing EBO pseudotypes. FR-alpha expression in Jurkat cells facilitated MBG or EBO entry, and FR-blocking reagents inhibited infection by MBG or EBO. Finally, FR-alpha bound cells expressing MBG or EBO GP and mediated syncytia formation triggered by MBG GP. Thus, FR-alpha is a significant cofactor for cellular entry for MBG and EBO viruses.

Audit of a one-stop breast clinic--revisited

BACKGROUND

A one-stop diagnostic service has been available for women with symptomatic breast disease at St Bartholomew's Hospital for 5 years and was originally audited in May 1993. In re-auditing the one-stop service our aim was to see if our practice had improved following the original audit and to look at the impact which these changes in practice had made to the service offered to the patient.

METHODS

A prospective audit of 4 consecutive clinics was undertaken in November 1997. A total of 300 patients (59 new and 241 follow up) were seen in clinic in this time. The primary outcome measure concerned the completeness of triple assessment in the 40 patients who required one stop investigations, including mammography, ultrasonography and fine-needle aspiration cytology. In addition, mean time to initial consultation and level of awareness of the one-stop facility and its attendant time delay were measured.

RESULTS

Of the 300 clinic attendees 40 (38 new, 2 follow-up) had one-stop investigations. As a result of the one-stop service being in practice, 36 patients (90%) had a definitive management decision made at their first outpatient visit. Of these 2 were symptomatic cancers, forming 5% of the workload. A total of 86% of the workload was benign. Four patients (10%) had equivocal results. The mean waiting time from designated appointment until surgical consultation was 36.7 minutes and was disappointingly unchanged from that of the previous audit. However this does not take into account the significant reduction in staffing levels which has occurred between the two periods of assessment.

CONCLUSIONS

The initial audit identified a significant problem with time constraints, necessitating that a large number of patients with carcinomas return at a later date for further investigations. Booking only new patients at the beginning of clinic has provided a solution. Disappointingly, our figures do not show a significant improvement in mean waiting time compared with the previous audit, despite allowing GPs greater access of referral. Encouragingly, we have been able to maintain a similar standard of provision of care despite lower staffing levels and to implement the changes suggested by the original audit (thereby closing the audit loop).

High frequency of promoter hypermethylation of RASSF1A in nasopharyngeal carcinoma

We have investigated the genetic and epigenetic changes of a newly isolated tumor suppressor gene on 3p21.3, RASSF1A, in nasopharyngeal carcinoma (NPC). Four xenografts, four cell lines and 21 primary tumors were examined. Promoter hypermethylation of the 5'CpG island of RASSF1A was detected in 4 of 4 (100%) xenografts, in 3 of 4 (75%) cell lines, and in 14 of 21 (66.7%) primary tumors but not in the normal nasopharyngeal epithelia. Mutations were found in 2 of 21 (9.5%) primary tumors. In the cell lines and xenografts with extensive methylation, no RASSF1A gene expression was found. After treatment with 5'-aza-2'deoxycytidine, reexpression and demethylation of the RASSF1A gene were detected in a NPC cell line. These findings suggest that promoter hypermethylation may participate in the transcriptional inactivation of the RASSF1A gene in NPC. The high incidence of RASSF1A alterations suggest that it is the critical target gene on chromosome 3p21.3 involved in the development of NPC.

Hospital care by hospital-based and clinic-based faculty: a prospective, controlled trial

BACKGROUND

The hospital length of stay decreases and clinical outcomes are maintained when teaching hospitals involve hospital-based attending physicians in comparison with traditional attending physicians. The attending physician's time commitment, including the number of hours per day and months per year, required to achieve this result is unknown. This study compared the clinical outcomes and cost of care for patients treated by hospital-based and clinic-based attending physicians devoting dramatically different amounts of time to supervising residents on the medical wards of a suburban county hospital.

METHODS

Patients were alternately admitted to 2 groups of ward teams. Faculty who attended 10 months of the year supervised one group. The comparison group's attending physicians were on service for 2 months or less and maintained clinic responsibilities while on service. The cost of patient care was compared by means of the length of stay, total hospital costs, and costs for ancillary services. Hospital mortality and readmission rates compared clinical outcomes.

RESULTS

There were 4456 patients hospitalized on the medical wards of a teaching service. No differences were detected in the length of stay (4.37 +/- 0.1 days for hospital-based and 4.39 +/- 0.1 days for clinic-based attending physicians). Hospital cost was observed to be similar (average cost, $5989 and $5977 per patient, respectively). The clinical outcomes were equivalent, with adjusted mortality rates for hospital-based attending physicians of 3.2% vs 3.9% for clinic-based attending physicians (P =.28).

CONCLUSION

An increase of faculty time and involvement for supervision of resident-managed hospital care did not improve clinical outcomes or decrease costs during the 1-year study period.

Effect of some enhancers on the permeation of haloperidol through rat skin in vitro

The objective of this work is to enhance the permeation of haloperidol through the rat skin in vitro by using various enhancers at a concentration of 1 mg/ml in the saturated drug solution and analysing the dose-dependent diffusion profile for the enhancers which significantly increased permeation at this concentration compared with the control. Enhancers belonging to various chemical classes like the vitamins (ascorbic acid), surfactants (cetrimide, polysorbate 20), sulfoxides (dimethyl sulfoxide), glycols (polyethylene glycol 400, propylene glycol) and amides (urea) were used. Amber glass Franz-type diffusion cells were used for the permeation studies and haloperidol was made soluble in aqueous solution with the aid of lactic acid. Ascorbic acid and cetrimide increased flux and permeability coefficient significantly. From the dose-dependent permeation studies, it was concluded that ascorbic acid enhanced the permeation by increasing the solubility of the drug in the vehicle thus providing a high concentration gradient across the skin, whereas cetrimide enhanced the permeation by increasing the thermodynamic activity which may be due to solubilization of skin lipids by micelles. Polysorbate 20 decreased the enhancer index by decreasing the thermodynamic activity. None of the enhancers changed the lag time except for urea which decreased the lag time probably by its binding with keratin. Dimethyl sulfoxide, polyethylene glycol 400 and propylene glycol did not have a significant effect on haloperidol permeation compared with control.

Expression of epidermal growth factor in transgenic mice causes growth retardation

The epidermal growth factor (EGF) family of peptides signals through the erbB family of receptor tyrosine kinases and plays important roles in development and tumorigenesis. Both EGF and transforming growth factor (TGF)-alpha only bind to erbB1 and activate it. The precursor of EGF is distinct from that of TGF-alpha in having eight additional EGF-like repeats. We have recently shown that the EGF precursor without these repeats is biologically active and leads to hypospermatogenesis in transgenic mice. Here we present evidence that the growth of transgenic mice widely expressing this engineered EGF precursor is also stunted. These mice were consistently born at half the normal weight and reached almost 80% of normal weight at adulthood. The mechanism involved a reduction of serum insulin-like growth factor-binding protein-3. Chondrocyte development in the growth plate was affected, and osteoblasts accumulated in the endosteum and periosteum. Besides these novel findings on the in vivo effects of EGF on bone development, we observed no sign of tumor formation in our transgenic animals. In contrast to previous reports on TGF-alpha transgenic mice, we show that the biological functions of EGF and TGF-alpha are clearly distinct.

Population pharmacokinetics of tacrolimus in Asian paediatric liver transplant patients

AIMS

The purpose of this study was to describe the population pharmacokinetics of intravenous and oral tacrolimus (FK506) in 20 Asian paediatric patients, aged 1-14 years, following liver transplantation and to identify possible relationships between clinical covariates and population parameter estimates.

METHODS

Details of drug dosage histories, sampling times and concentrations were collected retrospectively from routine therapeutic drug monitoring data accumulated for at least 4 days after surgery. Before analysis, patients were randomly allocated to either the population data set (n = 16) or a validation data set (n = 4). The population data set was comprised of 771 concentration measurements of patients admitted over the last 3 years. Population modelling using the nonlinear mixed-effects model (NONMEM) program was performed on the population data set, using a one-compartment model with first-order absorption and elimination. Population average parameter estimates of clearance (CL), volume of distribution (V) and oral bioavailability (F) were sought; a number of clinical and demographic variables were tested for their influence on these parameters.

RESULTS

The final optimal population models related clearance to age, volume of distribution to body surface area and bioavailability to body weight and total bilirubin concentration. Predictive performance of this model evaluated using the validation data set, which comprised 86 concentrations, showed insignificant bias between observed and model-predicted blood tacrolimus concentrations. A final analysis performed in all 20 patients identified the following relationships: CL (l h-1) = 1.46 *[1 + 0. 339 * (AGE (years) -2.25)]; V (l) = 39.1 *[1 + 4.57 * (BSA (m2)-0. 49)]; F = 0.197 *[1 + 0.0887 * (WT (kg) -11.4)] and F = 0.197 *[1 + 0.0887 * (WT (kg) -11.4)] * [1.61], if the total bilirubin > or = 200 micromol l-1. The interpatient variabilities (CV%) in CL, V and F were 33.5%, 33.0% and 24.1%, respectively. The intrapatient variability (s.d.) among observed and model-predicted blood concentrations was 5.79 ng ml-1.

CONCLUSIONS

In this study, the estimates of the pharmacokinetic parameters of tacrolimus agreed with those obtained from conventional pharmacokinetic studies. It also identified significant relationships in Asian paediatric liver transplant patients between the pharmacokinetics of tacrolimus and developmental characteristics of the patients.

DNA-liposome versus adenoviral mediated gene transfer of transforming growth factor beta1 in vascularized cardiac allografts: differential sensitivity of CD4+ and CD8+ T cells to transforming growth factor beta1

We have developed a model of transforming growth factor (TGF)beta1 gene transfer into mouse vascularized cardiac allografts to study the use of gene transfer as an immunosuppressive therapy in transplantation. Donor hearts were perfused with either DNA-liposome complexes or adenoviral vectors that encode the active form of human TGFbeta1. DNA-liposome mediated transfection prolonged allograft survival in approximately two-thirds of transplant recipients, while adenoviral delivery of TGFbeta1 was not protective. Protective TGFbeta1 gene transfer was associated with reduced Th1 responses and an inhibition of the alloantibody isotype switch. The protective effects of TGFbeta1 gene transfer were overridden by exogenous interleukin-12 administration. Interestingly, alloreactive CD4+ and CD8+ cells exhibited distinct sensitivities to TGFbeta1 gene transfer: CD4+ Th1 function was abrogated by this modality, although CD8+ Th1 function was not. Transient depletion of recipient CD8+ cells markedly prolonged the survival of grafts transfected with either DNA-liposome complexes or adenoviral vectors. Transgene expression persisted for at least 60 days, and Th1 responses were not detectable until CD8+ T cells repopulated the periphery. However, long-term transfected allografts appeared to exhibit exacerbated fibrosis and neointimal development. These manifestations of chronic rejection were absent in long-term transfected isografts, suggesting that long-term expression of active TGFbeta1 alone is not sufficient to induce fibrosis of the grafts. Collectively, these data illustrate the utility of immunosuppressive gene therapy as a treatment for transplantation when combined with additional conditioning regimens. Further, they illustrate that alloreactive CD4+ and CD8+ cells may be differentially influenced by cytokine manipulation strategies.

Differential morphometric and ultrastructural remodelling in the left atrium and left ventricle in rapid ventricular pacing-induced heart failure

BACKGROUND

Heart failure induced by rapid ventricular pacing (RVP) is associated with left atrial (LA) but not left ventricular (LV) hypertrophy.

OBJECTIVE

To determine whether differences in wall tension correlate with the differential ultrastructural remodelling in the LA and LV chambers, changes in ultrastructure, systolic function and wall tension (an index of wall stress) were compared in dogs after RVP (n=7) and with no RVP (n=9).

RESULTS

Compared with dogs with no RVP (controls), dogs with RVP had increased collagen volume fraction (5.3% versus 8.3%), myocyte cross-sectional area (245 versus 366 microm(2)) and hydroxyproline (222 versus 323 microg/mg protein) in the LA (all P<0.05), but not in the LV. The increase in systolic wall tension produced by RVP was greater in the LA (five versus 43 units, P<0.0004) than in the LV (227 versus 290 units, P<0.01) chambers and correlated closely with the collagen volume fraction (r=0.87), which in turn correlated with myocyte cross-sectional area (r=0.98). In the left atrium, wall tension correlated with wall stress (r=0.99).

CONCLUSIONS

The results suggest that differential wall tension may provide the stimulus for differential ultrastructural remodelling (with more hypertrophy and collagen) between LA and LV chambers in RVP-induced cardiomyopathy.

Cholelithoptysis: an unusual complication following laparoscopic cholecystectomy

A 75-year old lady underwent a routine laparoscopic cholecystectomy during which stones were spilled into the peritoneal cavity. Despite peritoneal lavage the patient developed chronic right upper quadrant discomfort and a pleural effusion over several months. Following the production of a pigmented bilirubin stone in her sputum the patient's symptoms resolved. Cholelithoptysis is a rare complication of laparoscopic cholecystectomy, the diagnosis should be considered in patients with prolonged chest symptoms after surgery.

2-hydroxypropyl-beta-cyclodextrin increases aqueous solubility and photostability of all-trans-retinoic acid

BACKGROUND

All-trans-retinoic acid (ATRA, vitamin A acid or tretinoin) is effective in the treatment of acute promyelocytic leukaemia (APL). Unfortunately, the oral absorption of ATRA is highly variable. Its poor aqueous solubility also makes it difficult to be formulated into parenteral formulation. To date, there is no parenteral formulation of ATRA available commercially.

OBJECTIVE

To undertake the preformulation work necessary for developing such a product.

METHOD

We investigated the solubility and stability profile of ATRA in various formulations.

RESULTS

The aqueous solubility of ATRA could be greatly increased by the inclusion of ATRA in 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD). Adjusting the pH value further improved the water solubility of ATRA. The photostability of HP-beta-CD-based formulation of ATRA was evaluated and it was found that inclusion ATRA into HP-beta-CD did improve the photostability of ATRA.

CONCLUSION

These results showed that it is possible to develop a parenteral formulation and/or an aqueous oral formulation of all-trans-retinoic acid by using 2-hydroxypropyl-beta-cyclodextrin. However, the biopharmaceutical properties of such a formulation would be necessary before its use.

Mannose-binding lectin and rheumatoid arthritis in southern Chinese

OBJECTIVE

Insufficiency of mannose-binding lectin (MBL) is associated with recurrent infections. Rheumatoid arthritis (RA) may represent an aberrant immune response to infections. This study examined the phenotypic expression and variant alleles of the MBL gene and its etiologic role in Chinese with RA.

METHODS

We studied 211 RA patients and 196 healthy subjects. Serum MBL concentrations and codon-54 mutation of the MBL gene and its promoter polymorphisms were analyzed. Clinical characteristics and disease activity were also examined.

RESULTS

Patients with RA had significantly lower serum MBL levels and higher frequency of codon-54 mutation of the MBL gene compared with controls. Additionally, there was a significant difference in the distribution of promoter polymorphisms, H/L, between RA patients and controls, although the frequencies of Y/X and those of nonstructural polymorphisms, P/Q, did not differ between the 2 groups. Furthermore, patients with RA had a lower incidence of the highest-producing haplotype HY and a higher incidence of the lowest-producing haplotype LX compared with controls. Serum MBL levels did not correlate with drug treatment or with disease activity. However, patients with erosive and serious extraarticular disease had significantly lower serum MBL levels than those without these disease manifestations at the time of study. Also, significantly more patients with erosive disease had a codon-54 mutation of the MBL gene compared with those with nonerosive disease.

CONCLUSION

The codon-54 mutation and low-producing promoter polymorphisms of the MBL gene are associated with RA. A low serum level of MBL predisposes to the development of RA and is a risk factor for severe disease in southern Chinese.

The angiopoietins, tie2 and vascular endothelial growth factor are differentially expressed in the transformation of normal lung to non-small cell lung carcinomas

The successful establishment of angiogenesis depends on a complex process of endothelial proliferation and organization. The angiopoietins (Ang-1 and Ang-2) and Tie2 ligand-receptor system is essential for the regulation of vascular maturation and stability during embryonic development. Together with the vascular endothelial growth factor (VEGF)-mediated pathway, they have been implicated in the control of normal physiological angiogenesis. We investigated their potential role and interaction in the development of lung cancers by comparing the expression pattern and inter-relationship of Ang-1 and 2, Tie2 and VEGF levels in 28 pairs of primary non-small cell lung cancers (NSCLC) and normal lung. Using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and in-situ hybridization (ISH), we showed that in NSCLC, there was significantly up-regulated VEGF expression by the tumour cells and an increased intensity of Ang-2 expression in the tumour vessels. The number of Ang-2-expressing vessels also correlated with the grades of tumour cell expression of VEGF. On the other hand, normal lung expressed constitutively high and correlated levels of Ang-1 and Tie2, which were significantly reduced in the carcinomas. The findings suggested a role of the Ang-1/Tie2 pathway in the maintenance of the complex vasculature in normal lung, while collaborative activities between the Ang-2 and VEGF pathways might be important in promoting tumour angiogenesis in NSCLC.

High resolution allelotype of microdissected primary nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a common cancer in South China but is rare in other parts of the world. To better understand the molecular basis of this cancer, we performed high-resolution allelotyping on 27 microdissected primary tumors using 382 microsatellite markers. We have detected high frequencies of allelic imbalance on 3p (96.3%), 9p (85.2%), 9q (88.9%), 11q (74.1%), 12q (70.4%), 13q (55.6%), 14q (85.2%), and 16q (55.6%). Nonrandom allelic changes of 12q and 16q were revealed for the first time. In addition, loss of heterozygosity on chromosomal arms 1p (37.0%), 5q (44.4%), and 12p (44.4%) were also common in NPC. Multiple minimally deleted regions, 7-40 cM, were identified at 3p14-24.2, 11q21-23, 13q12-14, 13q31-32, 14q24-32, and 16q22-23. Frequent deletions of these minimally deleted regions implied the presence of tumor suppressor genes that may be involved in the development of NPC. Consistent loss of heterozygosity on 3p, 9p, and 14q in almost all tumors suggested that such changes are critical events in NPC tumorigenesis.

Overexpression of epidermal growth factor induced hypospermatogenesis in transgenic mice

The in vivo role of epidermal growth factor (EGF) is not well defined even though its effects on culture cells were well studied. To understand the developmental, physiological, and pathological roles of EGF, we have generated transgenic mice widely expressing human EGF with the use of the beta-actin promoter. EGF and transforming growth factor alpha (TGFalpha) bind with equal affinity to the EGF receptor, a transmembrane tyrosine kinase, to trigger various biological responses. EGF and TGFalpha signaling are implicated in the development of the reproductive system. EGF also plays a physiological role in reproduction. Removal of the salivary gland in rodents, which reduces circulating EGF, reduces spermatogenesis, which can be corrected by EGF replacement. Here we show that in our transgenic males, only few post-meiosis II gametes were found, and the mice were sterile. This resembles a common cause of infertility in humans. Furthermore, the transgenic males had reduced serum testosterone. Our findings contrast the previous report on transgenic mice overexpressing TGFalpha in testis, which showed normal spermatogenesis. These data suggest that EGF is the active ligand for EGF receptor reported in germ cells, and proper EGF expression is important for completion of spermatogenesis.

Phase I open study of the effects of ascending doses of the cytotoxic immunoconjugate CMB-401 (hCTMO1-calicheamicin) in patients with epithelial ovarian cancer

PURPOSE

We have performed a phase I study of the cytotoxic immunoconjugate CMB-401 in women with epithelial ovarian cancer (EOC). CMB-401 is a directed chemotherapy that comprises a genetically engineered human antibody against polymorphic epithelial mucin, to which is attached covalently two to three molecules, on average, of the cytotoxic antibiotic calicheamicin. The primary objectives of this two-centre study were to identify end-organ toxicities and to establish the maximum tolerated dose (MTD).

PATIENTS AND METHODS

Thirty-four patients aged 37-75 years with progressive EOC not amenable to platinum/standard therapy, and with satisfactory WHO performance status (0-2) were recruited. Patients had received a mean of 3.2 previous chemotherapeutic regimens with a median interval since last chemotherapy of 182 days (range 34-1217). Patients received up to four cycles of a dual infusion of 35 mg/m2 hCTMO1 'predose' followed by doses of CMB-401 which were increased for each cohort--a regimen which minimises drug uptake in normal tissues whilst enhancing delivery to the ovarian tumour. CMB-401 dosing commenced at 2 mg/m2 and progressed via seven cohorts to 16 mg/m2.

RESULTS

CMB-401 was generally well tolerated. However, transient fever and emesis occurred, necessitating routine prophylaxis, and increasingly significant malaise was reported as the dose increased. WHO grade 3-4 toxicities, irrespective of causality, included: anaemia 21%, granulocytopenia 9%, thrombocytopenia 9%, liver transaminases 3%, sepsis 3%, haemorrhage 6%, nausea/vomiting 76%; pulmonary 6%, and conscious state/somnolence 6%. The MTD was reached at 16 mg/m2. During the study four patients had a greater than 50% reduction in CA125, and three patients had radiological evidence of reduction in tumour bulk.

CONCLUSIONS

CMB-401 appears to have an acceptable toxicity profile with demonstrable activity against EOC.

An efficient method of generating transgenic mice by pronuclear microinjection

Genetic transformation of mice using pronuclear microinjection was demonstrated by a number of groups in rapid succession in the early 1980's. Since that time, studies using transgenic animals have produced major advances in biomedical sciences and molecular genetics. More important, it is possible to study the molecular basis for tissue and stage-specific expression of genes. We recently used this method to generate transgenic mice. DNA fragment (transgene) was injected into the pronucleus of one-cell embryos. We describe this simplified protocol, which is reliable. With the use of buffered medium M2 for the whole process, it is not mandatory to have a CO2 incubator.

Distinct mechanisms of entry by envelope glycoproteins of Marburg and Ebola (Zaire) viruses

Since the Marburg (MBG) and Ebola (EBO) viruses have sequence homology and cause similar diseases, we hypothesized that they associate with target cells by similar mechanisms. Pseudotype viruses prepared with a luciferase-containing human immunodeficiency virus type 1 backbone and packaged by the MBG virus or the Zaire subtype EBO virus glycoproteins (GP) mediated infection of a comparable wide range of mammalian cell types, and both were inhibited by ammonium chloride. In contrast, they exhibited differential sensitivities to treatment of target cells with tunicamycin, endoglycosidase H, or protease (pronase). Therefore, while they exhibit certain functional similarities, the MBG and EBO virus GP interact with target cells by distinct processes.

Semiquantitative immunoblots of membrane protein-epidermal growth factor

Membrane proteins or cytokines are sometimes difficult to isolate and purify. Our group recently concentrated on epidermal growth factor (EGF) protein expression studies. Mature EGF was initially identified from mouse submaxillary gland extract as a stimulator of eyelid opening and incisor eruption when injected into newborn mice and rats. The EGF precursor is a transmembrane protein with eight additional EGF-like repeats. Our previous study has shown that the EGF precursor without these eight EGF-like repeats (hEGF) was biologically active. Here, we introduce a modified method for rapid detection of hEGF. The membranous protein was directly extracted from various organs of transgenic mice (including the submandibular gland, kidney, liver, heart, and testis) with two different buffers and easily detected by semiquantitative immunoblotting.

Bruton's tyrosine kinase mutations in 8 Chinese families with X-linked agammaglobulinemia

Bruton's tyrosine kinase (BTK) is involved in B-cell development. Mutation of BTK results in X-linked agammaglobulinemia (XLA). BTK is expressed in most haemopoietic lineages except mature T cells and plasma cells. We identified six novel and two known mutations of BTK in 11 Chinese XLA patients from 8 families. Family 1 had a novel point mutation at the start codon (135G-->T) in exon 2. Family 2 had known mutation of single A insertion in a stretch of 7 A residues (341-347insA) recognized as mutation hotspot in exon 3. Family 3 had a novel point mutation in exon 11 (1074A-->G) which led to aberrant splicing. Family 4 had known mutation in exon 19 (2053C-->T) in CpG mutation hotspot. The novel mutation of family 5 was an A deleted in a run of three As (1017-1019delA) in exon 10. In family 6, exons 2 and 3 were lost in BTK mRNA, a novel deletion. Family 7 had a novel substitution in exon 2 (227T-->C) which led to change of a conserved leucine to serine. Family 8 had a novel point mutation at beginning of intron 14 (IVS14+ 6 T-->G) resulting in aberrant splicing. Hum Mutat 15:385, 2000.

Kinetic study of a 2-hydroxypropyl-beta-cyclodextrin-based formulation of all-trans-retinoic acid in Sprague-Dawley rats after oral or intravenous administration

all-trans-Retinoic acid (ATRA, vitamin A acid, or tretinoin) is a potent chemotherapeutic agent for the treatment of acute promyelocytic leukemia (APL). Its poor aqueous solubility not only affects its oral absorption but also prevents it from forming an aqueous parenteral formulation. Recently, we developed a water-soluble formulation of ATRA with 2-hydroxypropyl-beta-cyclodextrin (HPbetaCD). In present study, this formulation was tested in Sprague-Dawley rats. Kinetic study of ATRA was carried out after oral or intravenous administration. Though there were no statistical differences in any of the estimated pharmacokinetic parameters between ATRA sodium salt and HPbetaCD-based ATRA after intravenous administration, inclusion of ATRA into HPbetaCD was found to greatly improve the oral absorption of ATRA.

Investigating plant-based medicines for wound healing with the use of cell culture technologies and in vitro models: a review

INTRODUCTION

Cell culture and molecular technologies are basic yet sophisticated research tool used to investigate plant-based medicine for wound healing.

METHODS

Cell viability and proliferation assay is used to determine whether there are any positive effects and to discover what is the limiting cytotoxic concentration in vitro. The scratch technique, fibroblast-populated collagen lattices and aortic rings embedded gels are used as the in-vitro models of wound re-epithelialization, contraction and angiogenesis. The immunofluorescence, immunoblotting and organotypic culture can be used to detect expression of specific proteins that are modulated by plant extracts during the wound healing process.

MAIN FINDINGS

Given the dynamics of the wound healing process, cell culture and molecular technologies are advantageous in providing us with detailed studies and analysis of each intricate process.

CONCLUSION

The scientific approaches for the study of traditional plant-based remedies for wound healing will provide us an important platform for rigorous testing and evaluation of their clinical efficacy based on accepted rules of evidence.

Viral entry through CXCR4 is a pathogenic factor and therapeutic target in human immunodeficiency virus type 1 disease

The chemokine receptors CCR5 and CXCR4 function as the principal coreceptors for human immunodeficiency virus type 1 (HIV-1). Coreceptor function has also been demonstrated for a variety of related receptors in vitro. The relative contributions of CCR5, CXCR4, and other putative coreceptors to HIV-1 disease in vivo have yet to be defined. In this study, we used sequential primary isolates and recombinant strains of HIV-1 to demonstrate that CXCR4-using (X4) viruses emerging in association with disease progression are highly pathogenic in ex vivo lymphoid tissues compared to CXCR4-independent viruses. Furthermore, synthetic receptor antagonists that specifically block CXCR4-mediated entry dramatically suppressed the depletion of CD4(+) T cells by recombinant and clinically derived X4 HIV-1 isolates. Moreover, in vitro specificity for the additional coreceptors CCR3, CCR8, BOB, and Bonzo did not augment cytopathicity or diminish sensitivity toward CXCR4 antagonists in lymphoid tissues. These data provide strong evidence to support the concept that adaptation to CXCR4 specificity in vivo accelerates HIV-1 disease progression. Thus, therapeutic intervention targeting the interaction of HIV-1 gp120 with CXCR4 may be highly valuable for suppressing the pathogenic effects of late-stage viruses.

Tissue-specific consequences of the anti-adenoviral immune response: implications for cardiac transplants

The immune response to adenoviral vectors can induce inflammation and loss of transgene expression in transfected tissues. This would limit the use of adenovirus-mediated gene transfer in disease states in which long-term gene expression is required. While studying the effect of the anti-adenoviral immune response in transplantation, we found that transgene expression persisted in cardiac isografts transfected with an adenovirus encoding beta-galactosidase. Transfected grafts remained free of inflammation, despite the presence of an immune response to the vector. Thus, adenovirus-mediated gene transfer may have therapeutic value in cardiac transplantation and heart diseases. Furthermore, immunological limitations of adenoviral vectors for gene therapy are not universal for all tissue types.

Isolation of Helicobacter pylori from vomitus in children and its implication in gastro-oral transmission

OBJECTIVE

The route of transmission of Helicobacter pylori (H. pylori) is unclear. Gastro-oral transmission via contaminated vomitus has been proposed as an important mode of transmitting H. pylori, especially in children. This pilot study attempted to isolate H. pylori from the vomitus of children.

METHODS

Children presenting for evaluation with gastroenteritis-associated vomiting were studied. Fresh vomitus samples were collected for detection of H. pylori by bacteriological culture and polymerase chain reaction, (PCR). A rapid, whole blood test was used to determine the H. pylori status of patients.

RESULTS

A total of 18 children with mean age of 6 yr were studied; four had a positive serology test. Among these four children, H. pylori was isolated from vomitus by culture in one child and by PCR in two. An 18-month-old girl with negative serology had H. pylori detected in vomitus by PCR. Six months later, she had seroconversion confirmed, suggesting that she had an acute H. pylori infection on initial presentation.

CONCLUSIONS

This is the first study reporting successful isolation of H. pylori from naturally produced vomitus. The result implies that transmission of H. pylori infection by vomitus, especially in children, is possible.

Expression of full length or truncated epidermal growth factor precursor transforms NIH3T3 fibroblasts

Epidermal growth factor (EGF) is derived from a large precursor (EGFP) of unusual structure. As EGFP remains unprocessed in certain tissues, it is of biological relevance to study its activity. Activation of the EGF receptor by EGF is involved in transformation of NIH3T3 fibroblasts. We isolated clones of NIH3T3 expressing full length, cytoplasmic region deleted or EGF-repeats deleted EGFP. All clones formed colonies in soft agarose and tumors in nude mice. Two clones expressing EGF-repeats deleted EGFP formed more and larger colonies. To conclude, EGFP is biologically active. Deletion of the 8 EGF repeats may enhance anchorage independent growth in NIH3T3.

Cytokine regulation of chronic cardiac allograft rejection: evidence against a role for Th1 in the disease process

BACKGROUND

Transient depletion of CD4+ T cells in cardiac allograft recipients prolongs allograft survival; however, grafts exhibit signs of chronic rejection characterized by collagen deposition and neointima development. Although it is believed that Th1 cells promote acute graft rejection, the role of these cells in chronic rejection remains unclear. Hence, our study evaluated whether Th1 cells are associated with the development of chronic cardiac allograft rejection.

METHODS

Splenocytes obtained from C57BL/6 recipients bearing BALB/c hearts with signs of chronic rejection were adoptively transferred into C57BL/6 SCID cardiac allograft recipients. As a measure of Th1 function, interferon-y production was determined after restimulation of recipient splenocytes with donor alloantigens.

RESULTS

Transfer of splenocytes in SCID allograft recipients resulted in accelerated chronic rejection in the majority of mice. Characterization of these cells before transfer revealed hyporesponsive Th1 function. However, donor-specific proliferative responses and precursor interleukin-2 producing helper and cytotoxic T lymphocyte frequencies were comparable to that of naive splenocytes. Further, splenocytes obtained from SCID recipients with advanced signs of chronic rejection remained deficient in Th1 function, suggesting that Th1 are not involved in this disease process. This possibility was further supported by the development of chronic rejection in IL-12 knockout recipients. Finally, when splenocytes used for adoptive transfer retained Th1 function, transfer of these cells into SCID recipients resulted in acute allograft rejection.

CONCLUSIONS

We have established a model in which the mediators of chronic rejection may be further explored. In this system, the absence rather than the presence of donor-reactive Th1 is associated with chronic rejection. These data indicate that Th1-independent effector mechanisms are responsible for chronic rejection in this model.

Is mammography of value in women with disseminated cancer of unknown origin?

Mammography is often requested to try to identify occult primary breast carcinoma in women with metastatic cancer of unknown primary site. This study aimed to investigate whether mammography is of use in these patients in identifying the breast as the origin of the metastatic disease. Thirty-one women with a working diagnosis of metastatic cancer underwent mammography in an attempt to determine the primary site. None of these women had a palpable breast mass. The site of presentation, pathological type of tumour, site of origin, and benefit of mammography and mammography-provoked biopsy were clarified for each patient. The patients were also followed up to determine survival. The commonest sites of presentation were lung (45%), lymph nodes (19%) and abdomen (16%). The primary sites of these cancers were identified with confidence in 27 patients (87%). The commonest known primary tumour sites were lung (45%), breast (16%) and ovary (16%). Abnormal mammograms were detected in four patients (13%), but three of these did not have breast cancer. In one, the site of origin remained indeterminate, as either breast or lung. Five (16%) had a confident diagnosis of breast carcinoma; all of these women had normal mammograms. We conclude that mammography in women presenting with metastatic disease from an unknown primary site is unhelpful and is not recommended. Furthermore, we could not demonstrate its value in women presenting with axillary lymphadenopathy.

Interleukin-12 (IL-12)-driven alloimmune responses in vitro and in vivo: requirement for beta1 subunit of the IL-12 receptor

BACKGROUND

Interleukin-12 (IL-12) mediates its biologic activities via binding high-affinity receptors on T and natural killer cells. Although emphasis has been placed on the requirement for IL-12Rbeta2 in IL-12 bioactivity, the role of IL-12Rbeta1 is less well defined. The current study evaluated the effects of exogenous IL-12 on alloantigen-specific immune responses and determined the requirement for IL-12Rbeta1 in IL-12-mediated alloimmunity.

METHODS

The mouse heterotopic cardiac transplant model was employed to evaluate the effects of IL-12 on alloantigen-specific immune responses in vivo. In addition, IFN-gamma production in mixed lymphocyte cultures (MLC) supplemented with IL-12 was measured to assess the effects of IL-12 on Th1 function in vitro. Mice deficient in IL-12Rbeta1 (IL-12Rbeta1-/-) were used to determine the requirement for this receptor component in IL-12-driven alloimmune responses.

RESULTS

Addition of IL-12 to MLC consisting of wild-type splenocytes enhanced alloantigen-specific proliferative responses and Th1 development. In contrast, IL-12 did not alter these in vitro immune parameters in IL-12Rbeta1-/- MLC. Treatment of wild-type cardiac allograft recipients with IL-12 resulted in high concentrations of serum interferon-gamma (IFN-gamma) and a 10-fold increase in IFN-gamma production by recipient splenocytes after restimulation in vitro. However, this fulminate Th1 response did not accelerate allograft rejection. Importantly, IL-12 had no effect on serum IFN-gamma or in vivo priming of Thl in IL-12Rbeta1-/- recipients. Finally, administration of IL-12 to WT allograft recipients resulted in a bimodal alloantibody response: antibody production was suppressed at high doses of IL-12, and enhanced at lower doses.

CONCLUSIONS

IL-12 markedly enhances alloantigen-specific immune function; however, these exaggerated Th1-driven responses do not culminate in accelerated allograft rejection. Further, these data indicate that IL-12Rbeta1 is essential for the enhancement of both in vitro and in vivo alloimmune responses by exogenous IL-12.

A trans-receptor mechanism for infection of CD4-negative cells by human immunodeficiency virus type 1

Chemokine receptors, particularly CCR5 and CXCR4, act as essential coreceptors in concert with CD4 for cellular entry by human immunodeficiency virus type 1 (HIV-1; reviewed in [1]). But infection of CD4(-) cells has also been encountered in various tissues in vivo, including astrocytes, neurons and microvascular endothelial cells of the brain [2] [3] [4] [5] [6], epithelial cells [5] [7], CD4(-) lymphocytes and thymocytes [8] [9], and cardiomyocytes [10]. Here, we present evidence for the infection of CD4(-) cell lines bearing coreceptors by well-known HIV-1 strains when co-cultured with CD4(+) cells. This process requires contact between the coreceptor-bearing and CD4(+) cells and supports the full viral replication cycle within the coreceptor-bearing target cell. Furthermore, CD4 provided in trans facilitates infection of primary human cells, such as brain-derived astrocytes. Although the pathobiological significance of infection of CD4(-) cells in vivo remains to be elucidated, this trans-receptor mechanism may facilitate generation of hidden reservoirs of latent virus that confound antiviral therapies and that contribute to specific AIDS-associated clinical syndromes.

Effects of sucrose, citric buffer and glucose oxidase on the stability of captopril in liquid formulations

OBJECTIVE

To study the effects of sucrose, citric buffer and glucose oxidase on the stability of captopril in liquid formulations.

METHOD

Captopril liquid formulations 1 mg/ml were prepared in various concentrations of syrup with and without citric buffer. The liquid formulations were stored in amber glass bottles at 5 degrees C. Samples were removed from these formulations at 0, 1, 2, 3, 4, 7, 10, 15, 20 and 30 days for assay of captopril by a stability-indicating high performance liquid chromatographic method.

RESULTS

Our findings indicate that low concentration of citric buffer (0.03 M) had a small stabilising effect on captopril in liquid formulations containing no or low concentration of sucrose (10% w/v). However, in formulations with higher concentrations of sucrose (30 and 85% w/v, respectively), the stabilising effect was not apparent. Captopril in 1 mg/ml formulations containing 0.03 M citric buffer and 10% w/v glucose degraded rapidly in the presence of glucose oxidase. The degradation was particularly evident at higher temperature. Glucose oxidase is an antioxidant, which can extensively reduce oxygen concentration in liquid formulations.

CONCLUSION

The stability of captopril is very sensitive to the presence of excipients. Many excipients can function as catalysts in its degradation. Even in the deficiency of oxygen, its degradation can also be substantial with suitable catalysts present in the liquid formulation.

V3 recombinants indicate a central role for CCR5 as a coreceptor in tissue infection by human immunodeficiency virus type 1

Binding of the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 to both CD4 and one of several chemokine receptors (coreceptors) permits entry of virus into target cells. Infection of tissues may establish latent viral reservoirs as well as cause direct pathologic effects that manifest as clinical disease such as HIV-associated dementia. We sought to identify the critical coreceptors recognized by HIV-1 tissue-derived strains as well as to correlate these coreceptor preferences with site of infection and dementia diagnosis. To reconstitute coreceptor use, we cloned HIV-1 envelope V3 sequences encoding the primary determinants of coreceptor specificity from 13 brain-derived and 6 colon-derived viruses into an isogenic (NL4-3) viral background. All V3 recombinants utilized the chemokine receptor CCR5 uniformly and efficiently as a coreceptor but not CXCR4, BOB/GPR15, or Bonzo/STRL33. Other receptors such as CCR3, CCR8, and US28 were inefficiently and variably used as coreceptors by various envelopes. CCR5 without CD4 present did not allow for detectable infection by any of the tested recombinants. In contrast to the pathogenic switch in coreceptor specificity frequently observed in comparisons of blood-derived viruses early after HIV-1 seroconversion and after onset of AIDS, the characteristics of these V3 recombinants suggest that CCR5 is a primary coreceptor for brain- and colon-derived viruses regardless of tissue source or diagnosis of dementia. Therefore, tissue infection may not depend significantly on viral envelope quasispeciation to broaden coreceptor range but rather selects for CCR5 use throughout disease progression.

An audit of patient acceptance of one-stop diagnosis for symptomatic breast disease

AIMS

The impetus for optimizing outpatient provision of breast-care services has come both from the patient and management in order to reduce anxiety and make full use of scarce resources. The one-stop diagnostic clinic for the investigation of symptomatic breast lesions is a relatively recent concept with well-known service benefits. However, acceptance to the patient has not been previously investigated.

RESULTS

The results of this prospective audit demonstrate a high level of patient satisfaction with the multi-disciplinary, one-stop breast clinic.

Genetic vaccination-induced immune responses to the human immunodeficiency virus protein Rev: emergence of the interleukin 2-producing helper T lymphocyte

Rev M10 is a trans-dominant negative inhibitor of HIV replication. Hence, stable transduction of CD4+ T cells with Rev M10 represents a novel gene therapy aimed at inhibiting HIV replication within these cells, thereby slowing the progression of AIDS. However, the immune system may recognize Rev M10 as foreign and target transduced cells for elimination. In the current study, mice were genetically immunized with a plasmid encoding Rev M10, to (1) identify immune parameters that may be induced by Rev M10 gene transfer, (2) determine the impact of repeated introduction of the Rev M10-encoding plasmid on the immune response to the transgene product, and (3) determine if cotransfection with a plasmid encoding TGFbeta1 would suppress the response. Kinetic studies revealed that Rev-specific IL-2-producing helper T lymphocytes (HTLs) appeared following the second genetic immunization, peaked after the third, and persisted at peak levels for at least 6 weeks. Rev-specific HTLs were CD4+, and the development of these cells was ablated by cotransfection with TGFbeta1. Other cytokines were not readily detectable when immune splenocytes were restimulated with Rev in vitro, and Rev-specific IgG antibodies were not present in the sera of these mice. To our knowledge, this represents the first report that genetic immunization with Rev M10 induces an immune response that is dominated by IL-2-producing HTLs. Further, this study demonstrates the potential utility of introducing immunosuppressive genes as a means to control the immune response to foreign transgene products.

C-erbB2 expression predicts response to preoperative chemotherapy for locally advanced breast cancer

BACKGROUND

Previous work suggests that the presence of c-erbB2 oncoprotein immunostaining and the proliferation rate of tumours, may be relevant to chemo-sensitivity in breast cancer.

PATIENTS AND METHODS

To investigate this we assessed pretreatment biopsies from 50 patients with locally advanced breast cancer for expression of c-erbB2 and MIB1 (proliferative marker) in relation to clinical response after 3 months preoperative chemotherapy.

RESULTS

Objective response was significantly more likely (22/30, 73%) for tumours negative for c-erbB2 membrane staining, compared to positively staining tumours (6/20, 30%, p = 0.0025). The percentage of cells staining positively for MIB1 was not predictive of response (p = 0.56).

CONCLUSIONS

This study has shown an increased likelihood of response to preoperative chemotherapy for breast cancers negative for c-erbB2 staining. Previous studies have shown that c-erbB2 immunostaining can correlate with either chemo-resistance or chemo-response. We postulate that this conflict may be due to differences in the type of chemotherapy administered. This raises the possibility of biological markers being use to assist in the selection of the type of chemotherapy regimen administered to particular tumour biological phenotype.

Association of systemic lupus erythematosus with promoter polymorphisms of the mannose-binding lectin gene

OBJECTIVE

To investigate the distribution of promoter variants of the mannose-binding lectin (MBL) gene and correlations between the promoter variants and serum MBL concentrations in Chinese patients with systemic lupus erythematosus (SLE) and in healthy Chinese controls.

METHODS

We studied the serum MBL levels and codon 54 mutation in 112 Chinese patients with SLE and 110 healthy controls. Genotyping of promoter variants of the MBL gene were done by polymerase chain reaction and allele-specific oligonucleotide hybridization.

RESULTS

We found significant differences in the distribution of the 2 pairs of promoter polymorphisms, H/L and Y/X, between SLE patients and controls (P=0.018 and P=0.019, respectively). Analysis of the correlation between promoter haplotypes and serum MBL levels revealed HY as the highest-producing, LY as the intermediate-producing, and LX as the lowest-producing haplotypes. The LX haplotype was present at a frequency of 0.259 in SLE patients and 0.154 in controls and was significantly associated with SLE (P=0.019, odds ratio 1.79, 95% confidence interval 1.12-2.85).

CONCLUSION

The low-producing promoter polymorphism of the MBL gene is associated with SLE, and a low serum MBL level is a risk factor for SLE. Even allowing for promoter polymorphisms and structural mutations of the MBL gene, serum MBL levels in SLE patients are still lower than those in controls, suggesting a trans-factor in regulating serum MBL levels.

Controlled multicentre study of the influence of subcutaneous recombinant human erythropoietin on anaemia and transfusion dependency in patients with ovarian carcinoma treated with platinum-based chemotherapy

This randomised controlled multicentre trial evaluated the effectiveness of recombinant human erythropoietin (rhEPO) in preventing anaemia and reducing the need for blood or erythrocyte transfusion in 122 ovarian cancer patients receiving platinum-based chemotherapy. The patients were randomly allocated to receive rhEPO 150 U/kg or 300 U/kg subcutaneously, three times a week, or open control. Patients also received up to 6 cycles of carboplatin or cisplatin, alone or in combination with other cytotoxic agents. Intention-to-treat analysis showed that 39.4% of patients in the control group received at least one blood transfusion, compared with 9.2% of patients treated with rhEPO. Patients treated with rhEPO experienced a significantly longer time to first erythrocyte transfusion than the control group and were less likely to experience nadir haemoglobin levels < 10 g/dl (P < 0.001 and < 0.05, respectively). A haemoglobin decrease < 1 g/dl during the first chemotherapy cycle, as well as a low baseline serum erythropoietin concentration, predicted a low transfusion need in rhEPO-treated patients but not in controls. During the study, 103 patients suffered at least one adverse event, but no serious, and only nine non-serious adverse events were considered possibly related to rhEPO therapy. These results indicate that treatment with rhEPO prevents anaemia, it reduces the need for blood or rhEPO erythrocyte transfusion in patients with ovarian cancer receiving platinum-based chemotherapy, and it is well tolerated. A starting dose of 150 U/kg of rhEPO, three times a week, may be recommended.

Sex difference in immunostaining of RET in the adult mouse kidney

The c-ret proto-oncogene encodes a receptor tyrosine kinase which is important for the development of the kidney and the enteric nervous system. During nephrogenesis, c-ret is expressed in the ureteric bud epithelium and later in its derivative, the collecting duct. This takes place during 11-17.5 days post-coitum (d.p.c.) in the mouse and our immunohistochemical study showed that the RET protein co-localized with the transcript. At 18.5 d.p.c. the kidney is fully differentiated. At 18.5 d.p.c., 1 week and 10 weeks old, RET was found in the proximal convoluted tubules, which is formed from the condensed mesenchyme. This suggests that c-ret may also play a role in kidney function. For the 10 weeks old kidney, RET immunostaining in male was concentrated on the basolateral side while female had a stronger staining in the whole cell. Furthermore, cytoplasmic staining was observed in male whereas both cytoplasmic and nuclear staining was found in female. c-ret transcript was detected by RT-PCR, and in situ hybridization showed its expression throughout the kidney. The reason for the sex-specific staining and the role of RET in kidney function remain to be determined.

Lipid-mediated gene transfer of viral IL-10 prolongs vascularized cardiac allograft survival by inhibiting donor-specific cellular and humoral immune responses

The gene encoding the immunosuppressive cytokine viral interleukin-10 (vIL-10) was introduced into BALB/c (H-2d) vascularized cardiac allografts by perfusing the graft vasculature with DNA-liposome complexes, utilizing the experimental cationic lipid gamma AP DLRIE/DOPE and a plasmid encoding vIL-10 under the control of the HCMVie promoter. The DNA to lipid ratio and DNA dose were critical factors in obtaining optimal biologic effects. Gene transfer of vIL-10 with a 3:1 DNA to lipid weight ratio using 375 micrograms DNA significantly prolonged allograft survival in MHC-mismatched C57BL/6 (H-2b) recipients (16.00 days) compared with both unmodified allografts (8.14 days) and vIL-10 antisense controls (8.28 days). Enhanced graft survival was specific to vIL-10 expression since treatment with antisense plasmid or anti-vIL-10 monoclonal antibody (mAb) abrogated the effect. Prolonged survival was associated with a novel histology characterized by a moderate mononuclear infiltrate, edema, and diffuse fibrillar/collagen deposition in the interstitium. Despite these morphologic changes, myocytes remained viable and vessels were patent. Limiting dilution analysis revealed transient infiltration of IL-2 secreting, donor-reactive, helper T lymphocytes (HTL) and cytotoxic T lymphocytes (CTL) in vIL-10 expressing grafts on day 7, that decreased significantly by day 14. Similarly, vIL-10 gene transfer inhibited the accumulation of donor-specific HTL and CTL in the spleen, compared with antisense controls. Prolonged survival was also associated with a marked decrease in IgM and IgG alloantibody production, with little to no IgG isotype switching. These results show that viral IL-10 gene transfer inhibits graft rejection in a clinically relevant model by inhibiting donor-specific cellular and humoral immune responses.

DNA diagnosis of FRAXA and FRAXE in Chinese children with neurodevelopmental disorders and fragile X syndrome

Fragile X (FraX) syndrome is the most common cause of inherited mental retardation. To see whether FRAXA or FRAXE can account for the etiology of some unexplained neurodevelopmental disorders in children, we screened for trinucleotide repeat expansion in a consecutive cohort of 73 Chinese children and their mothers seen in 1995 (group 1) referred for developmental assessment due to developmental delay, language delay, attention deficit hyperactivity disorder, autistic spectrum disorder, mental retardation and/or learning disability. We also screened DNA samples of all five previously diagnosed cytogenetically-positive FraX boys, their mothers and sisters (group 2). A control group of unrelated teenagers and adults were recruited from the community (group 3). In group 1, 3 families (2 mothers and a mother and her son) were found to carry a small premutation allele at FRAXA (premutation frequency = 2%, 3/153 independent X chromosomes), but none had any expansion at FRAXE. In group 2, all 5 FraX boys had full mutation at FRAXA and normal repeat length at FRAXE. In group 3, 1 male has a premutation allele out of 18 males and 59 females tested (premutation frequency of control = 0.7%, 1 out of 136 X chromosomes). For FRAXE screening in group 3, 2 females were carriers (1.5%, 2 out of 136 X chromosomes). Thus, FRAXA and FRAXE cannot account for the etiology of neurodevelopmental disorders in our cohort of Chinese children, and the prevalence of FRAXE mutation in normal Chinese population appears to be higher than reported in the Caucasians.

Alloantigen-reactive Th1 development in IL-12-deficient mice

IL-12p70, a 70- to 75-kDa heterodimer consisting of disulfide-bonded 35-kDa (p35) and 40-kDa (p40) subunits, enhances Th1 development primarily by its ability to induce IFN-gamma production by NK and Th1 cells. Although homodimers of the p40 subunit of IL-12 are potent IL-12 receptor antagonists in some systems, we have reported that p40 homodimer may accentuate alloreactive CD8+ Th1 function. To test the role of endogenously produced p40 in alloimmunity, Th1 development was assessed in either IL-12 p35 knockout (p35-/-) mice, the cells of which are capable of secreting p40, or p40 knockout (p40-/-) mice. Compared with IL-12 wild-type controls, splenocytes obtained from both p35-/- and p40-/- mice produced markedly less IFN-gamma after in vitro stimulation with Con A or alloantigens. Interestingly, in vivo-sensitized Th1 were detected in both p35-/- and p40-/- cardiac allograft recipients. However, in vivo Th1 development was enhanced in p35-/- recipients compared with p40-/- animals, suggesting that endogenous p40 produced in p35-/- mice may stimulate alloreactive Th1. Indeed, neutralizing endogenous p40 with anti-IL-12 p40 mAb reduced Th1 development in p35-/- allograft recipients to that seen in p40-/- mice. To determine whether Th1 development that occurred in the absence of IL-12p70 and p40 required IFN-gamma, p40-/- allograft recipients were treated with anti-IFN-gamma mAb. Neutralizing IFN-gamma did not inhibit in vivo Th1 development in p40-/- recipients and resulted in a unique pathology of rejection characterized by vascular thromboses. Collectively, these data suggest that 1) endogenous p40 may substitute for IL-12p70 in alloantigen-specific Th1 sensitization in vivo and 2) in vivo alloreactive Th1 development may occur independent of IL-12 and IFN-gamma, suggesting an alternate Th1-sensitizing pathway.

Up-regulation of lysozyme production in colonic adenomas and adenocarcinomas

AIMS

The presence of lysozyme protein in some gastric adenomas and adenocarcinomas has been well documented. There have been relatively few studies investigating the presence of lysozyme in tumours of the large intestine and they show contrasting results. We aim to investigate the cellular source and expression of lysozyme in colonic adenomas and adenocarcinomas.

METHODS AND RESULTS

We randomly selected 29 and 27 colonic adenomas and adenocarcinomas, respectively. Using in-situ hybridization (ISH) and immunohistochemistry (IHC), we found an up-regulation of lysozyme in the dysplastic epithelium of all the adenomas studied, with more than 80% of cases expressing moderate to strong signals. Although the up-regulation of lysozyme was also observed in adenocarcinomas, only 30% of the cases showed moderate to strong signals, mostly with an uneven distribution. Down-regulation of lysozyme in the severely dysplastic and invasive foci were noted in some cases of adenoma with malignant transformation. Normal colonic glands were consistently negative for lysozyme at both the mRNA and the protein level, but inflamed and immature regenerative colonic epithelium at the crypt base showed positive signals in a similar pattern to those observed in the dysplastic epithelium of the adenomas.

CONCLUSIONS

Our results confirm that colonic epithelium can produce lysozyme and its expression is up-regulated in the dysplastic epithelium in adenomas and in invasive cancer cells. It is interesting that regenerative colonic epithelium showed a similar pattern of lysozyme expression as in adenomas. The loss of lysozyme secreting phenotype in most of the invasive tumours suggests that lysozyme may not confer an advantage to tumour progression.

Stability of cefazolin sodium eye drops

OBJECTIVE

Assessing the stability of cefazolin sodium in preservative-free and preservative-containing eye drops.

METHOD

Extemporaneous formulations of eye drops were prepared from a commercially-available parenteral product of cefazolin sodium: eye drops 'A' contained 50mg/ml of cefazolin sodium in 0.45% w/v sodium chloride solution, and eye drops 'B' contained 50 mg/ml, 0.005% w/v thiomersal and 1% w/v glycerol in water-for-injection. Cefazolin sodium concentrations in these eye drops were monitored by a stability-indicating HPLC assay method. Measurements of pH and osmolality, as well as tests for microbial contamination, were conducted.

RESULTS

The eye drops stored at 4 degrees C were stable for 42 days with minimal changes in pH and osmolality, but eye drops stored at room temperature were only stable for a few days with greater increments in pH and osmolality. None of the samples cultured had bacterial or fungal growth after 7 days of incubation.

CONCLUSION

Extemporaneously prepared formulations of cefazolin are unstable at room temperature and should be stored in a refrigerator.

Expression of transforming growth factor alpha and epidermal growth factor receptor in adult polycystic kidney disease

Adult polycystic kidney disease (APKD) is a common genetic disease with a frequency of 1:1000. Evidence suggests that transforming growth factor alpha (TGF alpha) signaling may contribute to the hyperproliferation of the cystic epithelia in APKD. TGF alpha and epidermal growth factor (EGF) are well known mitogens expressed in the kidney and both exert their biological activities through binding to the same EGF receptor. A transgenic mouse that over-expressed TGF alpha developed renal cysts; raised levels of TGF alpha and EGF receptor mRNA were found in kidneys from two autosomal dominant APKD patients. To study the role of TGF alpha in cyst formation, we analyzed nine anatomically diagnosed adult polycystic kidneys and four normal kidneys using immunohistochemistry. We also traced the possible origins of the cysts by staining with the proximal convoluted tubule (PCT) marker, gp330, and the distal convoluted tubule (DCT) and collecting tubule (CT) marker, peanut agglutinin (PNA). In normal kidneys, TGF alpha protein was concentrated in the DCT and CT and EGF receptor protein in all three tubule types. In the early cysts of APKD, the cystic epithelia showed strong positive staining with TGF alpha, EGF receptor and gp330 but negative with PNA. Strong TGF alpha and EGF receptor staining was also found in the mixture of advanced cysts in the end-stage cystic kidneys although the cysts are likely to be derived from different segment of the renal tubules. This increased TGF alpha and EGF receptor expression in all cases and all types of cysts suggests that autocrine/paracrine stimulation by TGF alpha may be a common mechanism in cyst development in APKD.