Treatment of a human breast cancer xenograft with an adenovirus vector containing an interferon gene results in rapid regression due to viral oncolysis and gene therapy

Treatment of a human breast cancer cell line (MDA-MB-435) in nude mice with a recombinant adenovirus containing the human interferon (IFN) consensus gene, IFN-con1 (ad5/IFN), resulted in tumor regression in 100% of the animals. Tumor regression occurred when virus was injected either within 24 hr of tumor cell implantation or with established tumors. However, regression of the tumor was also observed in controls in which either the wild-type virus or a recombinant virus containing the luciferase gene was used, although tumor growth was not completely suppressed. Tumor regression was accompanied by a decrease in p53 expression. Two other tumors, the human myelogenous leukemic cell line K562 and the hamster melanoma tumor RPMI 1846, also responded to treatment but only with ad5/IFN. In the case of K562 tumors, there was complete regression of the tumor, and tumors derived from RPMI 1846 showed partial regression. We propose that the complete regression of the breast cancer with the recombinant virus ad5/IFN was the result of two events: viral oncolysis in which tumor cells are being selectively lysed by the replication-competent virus and the enhanced effect of expression of the IFN-con1 gene. K562 and RPMI 1846 tumors regressed only as a result of IFN gene therapy. This was confirmed by in vitro analysis. Our results indicate that a combination of viral oncolysis with a virus of low pathogenicity, itself resistant to the effects of IFN and IFN gene therapy, might be a fruitful approach to the treatment of a variety of different tumors, in particular breast cancers.

Expression of estrogen receptor variants in normal and neoplastic human uterus

Estrogen receptor variants lacking internal exons and representing dominant positive and negative activity may be involved in the initiation and/or progression of endocrine dependent tumors. To assess the role of estrogen receptor in uterine disease, we have analyzed both normal and neoplastic uterine samples for the presence of variant estrogen receptors using the sensitive technique of RT-PCR and direct automated DNA sequencing of the amplified products. Our analysis was conducted to determine the presence of spliced variants lacking exons 3 through exon 8. We demonstrate that both the normal and neoplastic human uterus contains a number of spliced variants of the estrogen receptor that co-exist with the wild type receptor. Variants lacking exons 4, 5 and 7 but not exons 3 and 6 were detected. Also, a novel partial deletion in exon 8 was detected in both the normal and neoplastic tissues, although a total deletion of this exon was not observed. In addition another region of exon 8 deletion was found to be present in one tumor tissue which also contained an insertion within this region, however, other tumors did not contain this variant. In addition, double exon deletion variants were observed lacking exons 3 and 4, exons 4 and 5, and exon 7 with part of exon 8. Although our data represents a limited number of samples it suggests that splicing of the estrogen receptor message occurs in the normal physiological setting. There does not appear to be any association between the presence or absence of spliced variants of estrogen receptor and uterine tumor formation at the mRNA level.

Gene therapy with an adeno-associated virus carrying an interferon gene results in tumor growth suppression and regression

Adeno-associated virus (AAV) vectors were constructed containing both a synthetic type I interferon gene, (IFN-con1) and the bacterial neomycin-resistant gene. Recombinant virions were used to infect a number of human tumor cell lines, including 293, Hela, K562, and Eskol (a hairy cell leukemia-like cell), and geneticin-resistant cells were selected. All IFN-con1-transduced cell lines produced low levels of IFN-con1 and grew at the same rate as nontransduced cell lines. Although these cell lines were resistant to IFN in vitro, when injected into nude mice, 293, K562, and Eskol cells failed to form tumors up to 3 months after the initial inoculum, although mice receiving nontransduced cells developed tumors within 7 to 10 days. Transduced Hela cells grew much slower in vivo and formed much smaller tumors than did the parental cells. When equal numbers of transduced and nontransduced cells were injected into nude mice, tumors initially developed slowly and then completely regressed. Treatment of an established Eskol tumor (histologically a malignant immunoblastic lymphoma) with AAV/IFN-con1-transduced 293 cells resulted in tumor regression, whereas treatment of Eskol tumors with IFN-con1 resulted in a small decrease in tumor size. These results indicate that the human IFN-con1 gene in a viral vector can be used successfully in the treatment of tumors both directly and by tumor-targeted gene therapy.

[Reconstruction of TMJ condyle cartilage defects with autogenous free periosteal grafts]

How to reconstruct the damaged articular cartilage has been one of the main subjects in treatment of articular disease for a long time. In this experimental study, fullthickness cartilage defects of 4 mm x 5 mm in size were created in rabbit's TMJ condyle cartiage on the left sides. The autogenous free periosteum were transplanted to the defects by using biological gelatin. Postoperatively, the animals were killed at intervals of 1, 2, 4, 8, 12 and 16 weeks. The regenerative cartilage in the defects were examined by gross appearance and histology. The result showed that mesenchymal cells in the cambium layer of periostum can transform into chondroblasts under the mechanical stress.

Amifostine improves the antileukemic therapeutic index of mafosfamide: implications for bone marrow purging

One of the principal challenges of cancer chemotherapy is the relative inability of most anticancer drugs to distinguish between normal and neoplastic tissues. Consequently, a broad range of toxicities are experienced by patients, especially myelosuppression. Amifostine, a phosphorylated aminothiol, increases the selectivity of specific anticancer drugs for neoplastic cells by protecting normal tissues. One potential application of this protector is during bone marrow purging to selectively remove contaminating cancer cells. This study took normal or leukemic marrow from human subjects and evaluated the ability of amifostine to selectively protect normal bone marrow progenitor cells versus leukemic progenitor cells from the cytotoxic effect of mafosfamide. The dose response of mafosfamide amifostine on leukemia colony-forming units or normal marrow progenitor cells was determined and the LD95 was calculated. Amifostine pretreatment resulted in a statistically significant protection of granulocyte-macrophage colony-forming units and erythroid blast-forming units from the toxicity of mafosfamide (P = .031). Thus, amifostine protection of normal marrow progenitor cells allows a higher LD95 concentration of mafosfamide to be used in ex vivo purging. In contrast, amifostine pretreatment increased the cytotoxicity of mafosfamide on the fresh human leukemia progenitor cells (P = .006). The dual effect of amifostine protection of normal marrow progenitor cells coupled with amifostine-induced sensitization of the leukemia cells increases the possible cell-kill of leukemic stem cells. With amifostine pretreatment, at the LD95 concentrations of mafosfamide for marrow progenitor cells, there was an estimated 6 log increase in cell-kill of the leukemia cells. This selective cell-kill offers the potential for lowering the incidence of leukemic relapse, while preserving more normal stem cells for autologous transplantation.

[An experimental study on the effect of operation at one side of the temporomandibular joint on the opposite side]

Condylectomy and menisectomy were performed in left TMJ of 14 rabbits, of them, 7 were treated with periosteal interposition and 7 without. Sixteen weeks after operation, condylar cartilage of the right side were studied and compared with 7 normal rabbits by means of histology and histochemistry. The results show that an operation of high condylectomy and menisectomy with or without interposition on one side of TMJ will result in degenerative changes in the other side (non-operated side). The degenerative changes in the rabbits without any interposition are more serious than those with periosteal interposition.

Amifostine (WR-2721) protects normal haematopoietic stem cells against cyclophosphamide derivatives' toxicity without compromising their antileukaemic effects

We compared the effects of amifostine (WR-2721) on the cytotoxicity of mafosfamide or 4-hydroperoxycyclophosphamide (4-HC) in normal marrow progenitor cells (CFU-GM) and leukaemic progenitor cells (CFU-L) during ex vivo purging for autologous bone marrow transplantation (ABMT). Mononuclear cells (MNC) were incubated with amifostine 3 mg/ml for 15 min, washed, and subsequently tested for their sensitivity to mafosfamide or 4-HC (20-200 micrograms/ 10(7) MNC/ml). The LD95 was significantly higher among amifostine-treated cells for PCM-CFU-GM in 6 of 13 patients and for 5R-CFU-GM in 4 of 10 patients (P < 0.05). In contrast, amifostine exhibited no protective effects upon CFU-L. The results of this study will show that amifostine protects normal late and early progenitor cells for the toxic effects of cyclophosphamide derivatives while preserving their antileukaemic effects. These results suggest that amifostine has therapeutic value as a protective agent for normal marrow progenitor cells during ex-vivo purging of bone marrow for ABMT.

Inflammatory intermediates produced by tissues encasing silicone breast prostheses

Silicone prostheses, when implanted within the soft tissues of the breast, evoke an inflammatory reaction. In response to silicone exposure, inflammatory mediator production by individual cells has been observed in various experimental studies. In this study, inflammatory mediator production by periprosthetic tissues (whole organ) was measured. The mediator levels were correlated with both the tissue histopathology of the periprosthetic capsules and the clinical symptoms noted by each patient. Tissue surrounding breast implants removed at surgery from ten women (average age and implant duration 40 and 7 years respectively) was cultured in vitro for 24 hours. Control tissues consisting of (a) augmentation mammaplasty skin scars from eight additional patients and (b) knee synovium from seven orthopedic surgery patients with arthritis undergoing primary joint arthroplasty were similarly cultured. The mediators [interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and prostaglandin E2 (PGE2)] liberated into the culture media were measured by an enzyme linked immunosorbent assay. When compared to controls, the mediator levels of IL-6 and TNF-alpha were substantially greater, although IL-2 and PGE2 were lower. Levels varied greatly from patient to patient: in pg/ml per 10 g tissue, IL-2 ranged from 10 to over 1,000; TNF-alpha from 100 to 1,000; IL-6 from 100 to 1,000,000; and PGE2 from 100 to 10,000. The correlation between TNF-alpha and PGE2 levels was .5 between IL-6 and PGE2 was .6, and between IL-6 and TNF-alpha was .77. The correlation between TNF-alpha and IL-6 was statistically significant at a p-value less than .01. Elevated levels of TNF-alpha production were associated with an increased number of macrophages and overall tissue cellularity (p < .05). No significant relationship was observed between mediator production and clinical symptoms. We conclude that overall cellularity, specifically macrophages, in the periprosthetic capsule may lead to TNF-alpha production but that cytokine production by periprosthetic tissues alone is not a predictor of clinical symptomatology in patients with silicone breast prostheses.

Comparison of some control strategies for three-compartment PK/PD models

In drug therapy, effective dosage strategies are needed to maintain target drug effects. The relationship between drug dose and drug effect is often described by pharmacokinetic/pharmacodynamic (PK/PD) models where typically the PK model has a multicompartment form and the PD model is the sigmoidal Emax model. The parameters in the PK/PD model are generally unknown in the individual patient, although prior knowledge may be available and can be updated after measurements of drug effect are taken during the therapy. This fact, together with the complexity of the PK/PD model, makes the control problem complex. This paper investigates several control strategies in the framework of a three-compartment PK model plus an effect site with a PD model. Using computer simulations under different assumptions, we show that a MAP (maximum a posteriori) Bayesian type of strategy is effective, nevertheless in high-risk situations a stochastic control strategy hedging against estimation errors provides better performance at computational cost.

Comparative effects of amifostine (Ethyol) on normal hematopoietic stem cells versus human leukemic cells during ex vivo purging in autologous bone marrow transplants

The protective action of amifostine (Ethyol, US Bioscience, Inc. West Conshohocken, PA) against the toxic effects of cyclophosphamide derivatives on the normal progenitor/stem cell pool was investigated. Early and late normal progenitor/stem cells were studied in the presence of placenta-conditioned medium (placenta-conditioned medium-granulocyte-macrophage colony-forming units); in the presence of granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interleukin-3, erythropoietin, stem cell factor (5R-CFU-GM); stimulated granulocyte-macrophage colony-forming and in a long-term culture-initiating cell assay. The preservation of an antileukemic effect was investigated by growing leukemic progenitor cells in the presence of phytohemagglutinin and leukocyte feeder layer with or without 25u interleukin-2. In 10 of 13 cases, a statistically significant (P < .05) protective effect was found on PCM-granulocyte-macrophage colony-forming units, in four of 10 cases on factor-stimulated granulocyte-macrophage colony-forming units, and in two of six cases on long-term culture-initiating cell. In contrast, amifostine exhibited no protective effect (none of nine cases) on leukemic progenitor cells. From the experimental data, it seems that amifostine is able to protect human normal progenitor/stem cells from cyclophosphamide derivative toxicity, while preserving their antileukemic effects. The therapeutic usefulness of such protection in autologous bone marrow transplantation with purged marrow is obvious.

Phosphorylation of PHAS-I by mitogen-activated protein (MAP) kinase. Identification of a site phosphorylated by MAP kinase in vitro and in response to insulin in rat adipocytes

PHAS-I is a heat- and acid-stable protein that is phosphorylated on Ser/Thr residues in response to insulin and growth factors. To investigate the phosphorylation of PHAS-I, the protein was expressed in bacteria and purified for use as substrate in protein kinase reactions in vitro. Recombinant PHAS-I was rapidly and stoichiometrically phosphorylated by mitogen-activated protein (MAP) kinase. At saturating MgATP, the Km and Vmax observed with PHAS-I were almost identical to those obtained with myelin basic protein, one of the best MAP kinase substrates. PHAS-I was also phosphorylated at a significant rate by casein kinase II and protein kinase C. To investigate sites of phosphorylation, PHAS-I was digested with collagenase and phosphopeptides were resolved by reverse phase high performance liquid chromatography. Almost all of the phosphate introduced by MAP kinase was recovered in the peptide, Leu-Met-Glu-Cys-Arg-Asn-Ser-Pro-Val-Ala-Lys-Thr. 32P was released in the seventh cycle of Edman degradation, identifying the Ser (Ser64) as the phosphorylated residue. Ser64 was also phosphorylated in response to insulin in rat adipocytes. We conclude that PHAS-I is a substrate for MAP kinase both in vivo and in vitro. As PHAS-I is one of the most prominent insulin-stimulated phosphoproteins in adipocytes, it may qualify as the major MAP kinase substrate in these cells.

Improved accuracy in direct automated DNA sequencing of small PCR products by optimizing the template concentration

Data are presented illustrating the optimum concentration range of reverse transcription PCR-generated products under 500 bp for accurate base calling with direct automated DNA sequencing. A 357-bp fragment of the human estrogen receptor, which includes the DNA binding domain of the protein, was used as a representative example of a gene fragment that can be rapidly amplified and sequenced. Using the Taq DNA polymerase dye terminator sequencing protocol and automated sequencing apparatus from Applied BioSystems, 0.1 to 1.0 pmol of PCR product in a 20-microL reaction volume provided > 97% accurate base detection. Concentrations greater or lower than this range increased the number of ambiguous bases due to alterations in the signal-to-noise ratios. This procedure has been successfully utilized with 140-440-bp PCR products within the optimum concentration range. These results show that low amounts of PCR products are necessary and sufficient for direct sequence analysis.

[Stereoscopic visual evoked potential elicited by static random dot stereogram]

Using 16.56' visual disparity stimulation produced by television random dot stereogram (TVRDS), we recorded visual evoked potentials (VEPs) elicited from 35 normal subjects with and without breaking their stereopsis and 28 stereoblind subjects. The results showed that a constant negative-positive wave complex was observed in 33 of 35 normal subjects; this negative-positive wave-complex disappeared when the stereopsis was artificially inhibited by a prism and in the stereoblind group, and no VEP wave was elicited in all of the stereoblind patients except in one with paralytic strabismus. The results revealed that under this condition the VEPs elicited by TVRDS were specific VEPs related to visual disparity stimulation and were stereoscopic ones. The TVRDS is an effective electro-physiological means to examine the stereopsis objectively and a new way to approach the occurrence and development of stereopsis.

Molecular cloning and tissue distribution of PHAS-I, an intracellular target for insulin and growth factors

Although the actions of insulin and a number of growth factors that signal via protein-tyrosine kinase receptors are believed to involve increased phosphorylation of key intracellular proteins, relatively few of the downstream phosphoproteins have been identified. In this report we describe a cDNA encoding one of the most prominent insulin-stimulated phosphoproteins in rat adipocytes. The cDNA encodes a protein, designated PHAS-I, which has 117 amino acids and a M(r) of 12,400. When translated in vitro and subjected to SDS/PAGE, PHAS-I migrates anomalously, having an apparent M(r) of 21,000. The predicted amino acid composition is interesting in that approximately 45% of the PHAS-I protein is accounted for by only four amino acids--serine, threonine, proline, and glycine. The PHAS-I gene is expressed in a variety of tissues, although the highest levels of mRNA are present in fat and skeletal muscle, two of the most insulin-responsive tissues. The nucleotide and deduced amino acid sequences of PHAS-I differ from any that have been reported, and homology screening provided no clues concerning the function of the protein. However, in view of its tissue distribution and the fact that the protein is phosphorylated in response to insulin, we speculate that PHAS-I is important in insulin action.

The chromatographic behaviour of cephalosporins in gel filtration chromatography, a novel method to separate high molecular weight impurities

The interaction between cephalosporins and the dextran matrix of Sephadex gel in gel filtration chromatography has been thoroughly studied. Twelve cephalosporins with specific structures were examined under different chromatographic conditions, including 12 different mobile phases comprising inorganic or organic compounds of different charge or/and density of electrons on their negative ions, different types of Sephadex gel (Sephadex G-10 and Sephadex G-50) and different flow rates. It was found that the more negative the charge or/and density of electrons on the negative ions of buffer components, the more was the adsorption of cephalosporins on the solid phase; this indicated tht the mobile phase played an important rôle in gel filtration chromatography for cephalosporins. By choice of suitable chromatographic conditions, optimum separation of high molecular weight impurities from cephalosporins could be achieved. The novel method could be used as a routine method for the quality control of cephalosporin preparations.

Presence of hepatitis B surface antigen (HBsAg)-specific cytotoxic T cells in asymptomatic HBsAg carriers

To investigate whether there is any evidence of an immune stimulation against hepatitis B virus surface antigen (HBsAg) in asymptomatic HBsAg carriers, proliferative and cytotoxic responses to HBsAg were measured in their peripheral blood lymphocytes. Although the majority of asymptomatic carriers had no proliferative response to HBsAg, 3 (25%) of 12 carriers showed significant T cell proliferation against HBsAg. In addition, using HBsAg-expressing autologous lymphoblastoid cell line (LCL) as target cells, HBsAg-specific cytotoxic activity was found in 2 of 3 asymptomatic HBsAg carriers who had a proliferative response against HBsAg. Furthermore, 6 cytotoxic T lymphocyte (CTL) clones were isolated from 1 asymptomatic carrier. The epitope recognized by 2 CTL clones was mapped to the major HBsAg residues 158-172. These CTL clones were able to produce interferon-gamma, tumor necrosis factor-alpha, or granulocyte-macrophage colony-stimulating factor. These findings demonstrate the presence of HBsAg-specific, major histocompatibility complex class I-restricted CTL in asymptomatic HBsAg carriers.

[Establishment of a primary eye care network and creation of a cataract-free zone in Shunyi County of Beijing]

Based on the epidemiological survey of eye diseases in 1985, a primary eye care network was established in Shunyi County of Beijing in 1987. Cataract surgery was the primary measure for the prevention of blindness, with the aim of creating a cataract-free zone in the county. The activities included (1) establishment of a County Guiding Committee for the prevention of blindness; (2) establishment of a 3-levelled primary eye care network and a referral and monitor system; (3) training of 7 ophthalmologists, 449 eye care workers and 6 optometrists; (4) extensive publicity of knowledge for the prevention of blindness; (5) screening of low vision and blindness in which 815 cataract blind patients were identified; and (6) conducting benefit ophthalmic counselling services. Up to December, 1991, 667 cataract operations were performed, representing 81.84% of the total cataract blind, to meet the qualifications of a cataract-free zone. 90.64% of the blind were restored sight and 59.16% of the blind were able to resume work. Operative infection occurred in none and 97.42% of the operations had no complication.

An efficient control strategy for dosage regimens

In medical drug therapy, efficient dosage strategies are needed to maintain target drug concentrations. The relationship between the concentration of a drug and the dosages is often described by compartment models in which the parameters are unknown, although prior knowledge may be available and can be updated after blood samples are taken during the therapy. Currently MAP (maximum a posteriori) Bayesian is the most often used control strategy in this setting. We show by simulation in a one-compartment context that the performance of the MAP Bayesian strategy depends on the assumptions in prior distribution of the parameters as well as the cost function. We propose an alternative control strategy, VU, that outperforms and is more robust than the MAP Bayesian strategy in a variety of problem settings.

Cytomegalovirus DNA in arterial walls of patients with atherosclerosis

The biological properties of cytomegalovirus (CMV) are consistent with a potential role in the pathogenesis of atherosclerosis. The evidence of such a role has so far been circumstantial, but CMV nucleic acid is beginning to be reported with increasing frequency in the arterial wall. Arterial specimens from 135 patients who underwent vascular surgery for symptomatic atherosclerotic vessel disease were analyzed by PCR for the presence of CMV nucleic acid. Samples were studied from the atheromatous plaque area and from uninvolved aortic tissues of patients undergoing surgery for vascular disease. One primer pair (LA) was used for detection of a late gene, and two other primer pairs (E1 and E2) were used for the immediate early gene region. Serum antibody to CMV was measured by radioimmunoassay. With the late gene primer, CMV nucleic acid was found in 76% of the tissue specimens tested, whereas the E2 gene primer complementary to the transforming mtr2 region was reactive in 90% of the arterial samples. There was no significant difference in the prevalence of CMV DNA in atherosclerotic plaque tissue and in uninvolved aortic tissue from the patients. A second early gene primer was not reactive with the tissue specimens, although it gave positive results with the positive control of infectious virus. Serum antibody to CMV was detected in 86% of the patients in whose tissue CMV DNA was demonstrated. CMV DNA was detected in a high proportion of atherosclerotic plaque tissues as well as in uninvolved aortic tissue of surgical patients, suggesting that latent CMV infection of the arterial wall may be a common occurrence in patients with atherosclerosis.

What are the implications of cardiac infection with cytomegalovirus before heart transplantation?

To elucidate prognostic implications of recipient cytomegalovirus infection before heart transplantation, we prospectively followed the clinical outcome of 21 transplant recipients whose explanted hearts (myocardium and coronary arteries) were first examined for the presence of cytomegalovirus DNA with polymerase chain reaction. Subsequently, serial endomyocardial biopsy tissue samples obtained from the allograft during routine evaluation for rejection were analyzed by polymerase chain reaction for both an immediate early and late cytomegalovirus gene region of cytomegalovirus DNA. Humoral cytomegalovirus immunoglobulin G antibodies were also measured by radioimmunoassay. Both early and late antigens were present in 14 of 21 (67%) explants from patients with (12 of 15 explants) and without (2 of 6 explants) pretransplant cytomegalovirus antibodies. Although the presence of both early and late antigens was uncommon in allografts the first week after transplantation (5 of 20 allografts, 25%), their presence significantly increased at 1 month (14 of 21 allografts, 67%) and 2 to 3 months (13 of 17 allografts, 77%) regardless of pretransplantation cytomegalovirus antibody status. The presence of both early and late antigens in explant tissue strongly predicted allograft virus status during the follow-up periods. Of five patients in whom clinical cytomegalovirus disease subsequently developed, all had explants positive for both early and late antigens, and all allografts were positive for early and late antigens within 1 month after transplantation. These are the first prospective data to correlate pretransplantation serum antibodies and explant polymerase chain reaction status with the development of future allograft infections and overall clinical outcome.

Intravitreal pharmacokinetics of liposome-encapsulated amikacin in a rabbit model

BACKGROUND

Intravitreal injection of antibiotics has become a standard therapy for bacterial endophthalmitis. The duration of effective antimicrobial levels in the vitreous after single injection, however, may not be long enough to get optimal response. The authors prepared liposome-encapsulated amikacin for prolonging the duration of intravitreal therapeutic concentrations and investigated the intravitreal pharmacokinetics of the liposomes and amikacin in phosphate buffer solution (PBS) as control.

METHODS

The liposome-encapsulated amikacin was prepared by reverse-phase evaporation method. The intravitreal pharmacokinetics of the liposomes was compared with amikacin in PBS by fluorescence polarization immunoassay. Albino rabbits were randomly distributed into 12 groups. Rabbits in groups 1 to 6 and in groups I to VI (control groups) received an intravitreal injection of the liposome-encapsulated amikacin and amikacin in PBS, respectively.

RESULTS

The encapsulation rate of amikacin was 91%. The time of 50% spontaneous degradation (half-life) of the liposomes in PBS (38 degrees C, pH 7.4) was 47.6 days, and the time of 50% release (half-life) of the drug from the liposomes in PBS was 84.8 hours. The vitreous amikacin concentrations in groups 1 to 6 were significantly greater (P < 0.05) than those in control groups I to VI in every time interval, except in groups 1 to 3 at 1 hour after injection. The difference was particularly obvious in the endophthalmitis groups. The clearance of encapsulated amikacin in vitreous appeared to be related to the state of blood-ocular barrier and to the structural integrity of vitreous. The distribution, the absorption, and the elimination of encapsulated amikacin in vitreous showed the first-order kinetics.

CONCLUSION

The liposome-encapsulated amikacin prolonged half-life of the drug in vitreous. The results of the pharmacokinetic analysis suggested that in endophthalmitis, especially in severe cases, the liposomes may be preferable to conventional preparation.

A simple technique for blood collection in the pig

A simple technique for blood collection in pigs of body weight 15-40 kg is described. The subcutaneous abdominal vein was used for rapid collection of 5-20 ml of blood samples. The animals were premedicated with 10 mg/kg of ketamine and 600 micrograms of atropine given intramuscularly prior to blood collection.

An open reading frame in the Rhodospirillum rubrum plasmid, pKY1, similar to algA, encoding the bifunctional enzyme phosphomannose isomerase-guanosine diphospho-D-mannose pyrophosphorylase (PMI-GMP)

The nucleotide sequence of a BglII fragment (3188 bp) from the plasmid pKY1 of Rhodospirillum rubrum was determined. A significant similarity was found between the amino acid sequences deduced from the nucleotide sequence of BglII fragment with that of algA, encoding the bifunctional enzyme with both the activities of phosphomannose isomerase and guanosine diphospho-D-mannose pyrophosphorylase of Pseudomonas aeruginosa.

Gastrointestinal manifestations of neurofibromatosis in childhood

Von Recklinghausen's neurofibromatosis (VRN) is a familial disorder characterised by a generalized neuroectodermal dysplasia--symptomatic involvement of the gastrointestinal tract is rare. We report on our experience with two children who had proven gastrointestinal neurofibromas and highlight the need for careful assessment in children with VRN who develop abdominal pain.

[Radioimmunoassay of serum and CSF myelin basic protein and its application to patients with acute cerebrovascular accident]

Myelin basic protein (MBP) was measured in the serum and CSF of patients with acute cerebrovascular disease (CVD, 34 cases), demyelinating disorders (DMD, 30 cases) and other neurological diseases (OND, 26 cases) by using a double antibody radioimmunoassay (RIA). Patients with acute CVD had a mean serum MBP concentration and positivity rate much higher than those with DMD and OND. The differences were significant (P < 0.05). In CSF, MBP levels in patients with acute CVD and patients with DMD were significantly greater than those in OND patients (P < 0.05). The results also show that there was a linear relationship between the CSF MBP levels and the serum MBP levels in patients with acute CVD (r = 0.72, P < 0.01), but no such relationship in patients with DMD and OND. The amount of serum MBP was also significantly correlated to the severity of acute CVD, to the level of consciousness disorder and limb paralysis, and to the extent and site of the cerebral lesion at CT-scan (P < 0.05). This study shows that the measurement of brain specific MBP in serum as a marker of cerebral damage may have clinical value in the diagnosis and prognosis of patients with CVD.

A study of the detection of sperm antibody in cervical mucus with a modified immunobead method

OBJECTIVE

To develop a new immunobead binding test (IBT) procedure that will detect sperm antibody in cervical mucus (CM), especially in very small samples of mucus.

DESIGN

After the interaction of donor sperm with bromelin-dissolved CM, the motile sperm cells were separated from other cells and debris and then tested with a standard immunobead method.

SETTING

The CM and serum samples were obtained from a sequence of referred patients who were sent to this testing laboratory.

PATIENTS

There were 60 women who provided 64 samples of CM and 41 samples of blood serum. They were partners in infertile couples.

INTERVENTIONS

None.

MAIN OUTCOME MEASURE

A useful distinction was made between positive and negative results for the mucus samples by this CM-IBT procedure. The usable samples of mucus could be as little as 0.05 g (wet weight).

RESULTS

From the 60 women, seven mucus samples were positive; in the repeated testing, the same results were obtained with five of the six positive samples and seven of seven negative samples.

CONCLUSION

This method (CM-IBT) can be clinically useful for detecting sperm antibody in CM, especially because it is effective for tiny samples. In this method, the motile sperm cells are better separated from the debris after the incubation step. When the IBT was applied to the serum samples from the same women, there was no correlation between serum-IBT and CM-IBT, showing that both materials must be tested.

Immunopharmacological activity of cefodizime in young and elderly subjects: in vitro and ex vivo studies

The biological response modifying activities of cefodizime (CDZ), a new third-generation cephalosporin, were investigated in vitro and ex vivo. In vitro investigations using cells isolated from the blood of young healthy donors showed no stimulating activity of CDZ on peripheral blood lymphocytes, natural killer cell activity, IL-1 production by adherent mononuclear cells, PMN chemiluminescence or PMN chemotaxis. A slight but statistically insignificant increase in PMN phagocytosis and phagocytic index was observed in the same population. IL-1 production was increased in three subjects with low resting state values. In a controlled ex vivo study, 20 healthy elderly subjects selected on the basis of depressed phagocytic function were treated with CDZ 1 g i.m. b.i.d. or placebo for eight days. PMN function was determined at baseline and on the day after the last dose. In the CDZ group a significant increase in both phagocytosis and phagocytic index was found, while there were no changes in the placebo group. In conclusion, CDZ restored depressed PMN phagocytic function in a population of elderly subjects. Patients with impaired PMN function who require antibiotic treatment may benefit from this activity of CDZ.

Internalization of CD4 molecules in human T-cells demonstrated by immuno-electron microscopy

Internalization of CD4 molecules on human CD4-enriched T-cells was demonstrated by immunocytochemical electron microscopy. CD4+ T-cell subclones were obtained from normal human peripheral blood, followed by one-way MLC screening and co-culturing with IL-2. Fixed and non-fixed T-cell samples were indirectly immunolabeled with mouse anti-human CD4 monoclonal antibody and goat anti-mouse IgG conjugated with peroxidase. Unfixed T-cells were immunolabeled at 4 degrees C and then re-incubated for 5-45 min at 37 degrees C. The selected CD4+ T-cell subclones showed strong CD4 binding on the cell surface after IL-2 incubation. However, fresh T-cells, monocytes, bone marrow cells and CD8+ T-cells all stained negative for CD4. The distribution of CD4 molecules on the fixed cell surface showed a homogeneous pattern. Capping and internalization of CD4-antibody-peroxidase complexes from the cell surfaces were observed follow a pathway of receptor-mediated endocytosis in unfixed T cells. Endocytotic vesicles, vacuoles of diverse sizes and shapes near the cell membrane or deep in the cell center were found to contain CD4 molecules. Negatively stained Golgi saccules were observed up to 45 min after re-incubation. These results suggest that increased CD4 molecules can be induced on the surface of normal human T-cells in vitro. Internalization and accumulation of CD4 molecules occurred in CD4-enriched T-cells with IL-2 pretreatment.

Fentanyl and medetomidine anaesthesia in the rat and its reversal using atipamazole and either nalbuphine or butorphanol

The intraperitoneal injection of anaesthetic agents is a simple and convenient method of anaesthetizing rats. However, all of the anaesthetic combinations in current use which are administered by intraperitoneal injection produce prolonged sedation, and full recovery of consciousness may take several hours. Fentanyl, a mu agonist opioid, and medetomidine, an alpha 2-adrenoceptor agonist were mixed and administered as a single intraperitoneal injection. Combinations of 300 micrograms/300 micrograms/kg and 300 micrograms/200 micrograms/kg of fentanyl/medetomidine were shown to produce surgical anaesthesia in the rat. This anaesthetic regimen produced significant respiratory depression (P less than 0.01) and animals did not regain their righting reflex until 193 +/- 21 min (mean +/- 1 SD) after injection. Administration by intraperitoneal injection of atipamezole, a specific alpha 2-adrenoceptor antagonist (1 mg/kg) mixed with a mu antagonist/k agonist opioid (nalbuphine, 2 mg/kg or butorphanol 0.4 mg/kg), resulted in a rapid (less than 8 min) reversal of anaesthesia and the associated respiratory depression, and apparent full recovery of consciousness.

[Photochemically induced focal cerebral infarction in rat and its pathological observation]

Cerebral infarction in Wistar rats was induced by photochemical method. A photochemical reaction was produced by the photosensitive agent rose bengal under the effects of green light (560 +/- 60 nm). This reaction released free radicals which may damage the endothelium of cerebral vessels and induce platelet aggregation, and then may cause thrombosis in cerebral parenchymal vessels. There were typical changes of thrombosis and ischemic necrosis in the irradiated region of the cerebrum under light and electron microscopy. Serial pathologic findings suggested that the critical phase of progressive necrosis lies at the time of 1-6 hours after cerebral ischemia induced photochemically. Therefore, effective protection of the brain is important in the early stage of cerebral ischemia.

Glycosylation is not required for ligand or receptor binding by expressed rat intrinsic factor

A cDNA clone encoding rat intrinsic factor (IF), pIFQ, has been inserted into the eukaryotic expression vector pSVL and used to transfect COS-1 cells. The IF produced by the transfected cells was secreted nearly exclusively into the medium at concentrations of 0.1-0.2 micrograms/ml. Tunicamycin treatment (1-10 micrograms/ml) completely blocked N-linked glycosylation but had no effect on IF secretion. The secreted glycosylated IF retained all the properties of native IF, i.e., high affinity for cobalamin (Cbl) and for the IF-Cbl receptor and relative resistance to low pH and to proteolysis. The nonglycosylated IF also retained these properties except that it was more protease sensitive. The protease degradation was prevented by the presence of the ligand Cbl. The presence of carbohydrate may play a role in protecting IF from digestion by pancreatic proteases in the intestinal lumen.

Gas chromatographic determination of aldicarb and its metabolites in urine

A method is described for the determination of aldicarb and its metabolites (the sulphoxide and sulphone) in urine by gas chromatography with flame photometric detection (GC-FPD). The sample was concentrated with a column containing activated charcoal and Florisil, and then eluted with dichloromethane-acetone (1:1, v/v). The aldicarb and aldicarb sulphoxide in the eluate solution were oxidized to aldicarb sulphone and the total sulphone concentration was determined by GC-FPD after extraction with dichloromethane and clean-up with an activated charcoal column. The detection limit was 0.0024 mg/l. The mean recoveries from spiked urine in the range 0.04-0.12 mg/l were 90.9%, 86.6%, 92.6% for aldicarb, aldicarb sulphoxide and aldicarb sulphone, respectively.

[A new serotype of Shigella boydii]

Two strains which belong to the same serotype of Shigella were isolated from the bloody-pus stool of two patients (in 1986) and is reported in this paper. The results were identical both showing agglutination in low titer with serotype 8 of S. dysenteriae and serotype 4 of S. boydii when the two strains were checked well with all kinds of diagnostic antisera and vice versa, ie the antisera produced by the two strains were also checked well with sera prepared with the representative strains of all Shigella spp. No cross agglutination with O6, O7, and O150 of E. coli were found. Consequently, It appears to be a new serotype of Shigella. These two strains possess the ability of causing keratitis in guinea-pigs as well as invading epithelial cells, the DNA of both strains in agarose-electrophoresis showed a large plasmid, indicating that they are virulent strains possessing invasive ability. It was concluded that these two strains belonged to Shigella boydii as they fermented mannitol and non-related antigenically with Shigella flexneri. Since serotype 1-18 of S. boydii have been reported recently, we propose that this new serotype should be serotype 19 of Shigella boydii.