Hartmann's procedure: an appraisal.

Ninety-seven patients underwent Hartmann's procedure between 1981 and 1986 at the University Hospital, Nottingham. Sixty-one (63%) required this operation as an emergency procedure. There was an overall mortality of 22% and the morbidity rate was 56%. Infective and cardiovascular problems accounted for 77% of all complications encountered reflecting the age and underlying condition of the patients requiring this procedure. Thirty patients had successful restoration of intestinal continuity, the majority of these having their original procedure performed as an emergency for benign disease. There were no immediate postoperative deaths from reanastomosis and few short- or long-term anastomotic problems, however there was again considerable postoperative morbidity.     

New xenograft model for assessing experimental therapy of central nervous system tumors: human glioblastoma in the intrathecal compartment of the nude mouse

Ten congenitally athymic "nude" mice and 10 immunocompetent mice underwent intrathecal inoculation with a human glioblastoma cell line (U87MG) via percutaneous lumbar puncture (5 x 10(5) cells/animal). All of the nude mice developed paraplegia with or without incontinence at 2 weeks and routinely died of inanition 3 weeks postimplantation. Histological examination confirmed extensive proliferation of neoplastic cells within the intrathecal space. A second group of animals was inoculated with 5 x 10(4) cells/animal: 20 nude mice, 10 cyclosporine A-immunosuppressed animals, and 10 immunocompetent control mice. The 20 mice were further divided into four subsets. Subset A did not receive chemotherapy, Subset B received 200 mg of carmustine (BCNU) per m2 by intraperitoneal injection, Subset C received a single dose of 4 mg of methotrexate (MTX) per m2 by intrathecal injection 4 hours after tumor inoculation, and Subset D received 12 mg of intrathecal MTX per m2. Decreasing the concentration of cells per animal by 1 log doubled the time interval required for the development of paralysis and incontinence to 4 weeks. Treatment with intrathecal MTX at a dose of 4 mg/m2 extended the symptom-free period by an additional week (to 5 weeks postinoculation), and a dose of 12 mg/m2 allowed an average of 6 weeks before the onset of neurological impairment. The xenografts did not grow in the immunocompetent control mice, the BCNU-treated group, or the cyclosporine A-immunosuppressed animals. An intrathecal xenograft model of central nervous system malignancies allows a novel approach to the evaluation of experimental chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Activation of second-messenger pathways reactivates latent herpes simplex virus in neuronal cultures.

Herpes simplex virus type 1 (HSV-1) establishes latent infections in neurons of sympathetic and sensory ganglia in humans, and reactivation of latent virus results in recurrent disease. Previously, we reported establishment of latent HSV-1 infections in neuronal cultures derived from rats, monkeys, and humans; reactivation occurs following nerve growth factor (NGF) deprivation. The processes controlling HSV latency are not understood. Using the in vitro neuronal latency system, we have shown that latent HSV-1 reactivated in response to stimulation of at least two second-messenger pathways. Stimulation of cAMP-dependent pathways by several mechanisms or activation of protein kinase C by phorbol myristate acetate (PMA) resulted in reactivation of latent HSV-1. The reactivation kinetics following treatment with activators of protein kinase A and C were accelerated compared with those following NGF deprivation. 2-Aminopurine, which inhibits NGF-stimulated protein kinases and other classes of protein kinases, but does not effect protein kinase A or C, blocked reactivation produced by NGF deprivation or treatment with a cAMP analog, but not reactivation by PMA treatment. These results demonstrate that latent HSV-1 reactivates in neurons in vitro in response to activation of second-messenger pathways.     

Misidentification of toxigenic Corynebacterium diphtheriae as a Corynebacterium species with low virulence in a child with endocarditis.

A 6-year-old boy presented to a university hospital in Malaysia with infective endocarditis complicating cyanotic congenital heart disease. Blood cultures showed a gram-positive, aerobic, coryneform-like bacillus identified by the hospital laboratory as Corynebacterium xerosis, but a reference laboratory identified the organism as a toxigenic strain of Corynebacterium diphtheriae. The two laboratories concurred on all biochemical test results except for sucrose fermentation.     

C1-esterase inhibitor blocks T lymphocyte proliferation and cytotoxic T lymphocyte generation in vitro

We have previously shown that activated C1s complement and activated T cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation of desLys58 beta2m. This process can specifically be inhibited by C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed lymphocyte culture (MLC) increased the endogenous production of IL-2 and the generation of allo-specific cytotoxic T lymphocytes. C1-inh was purified from fresh human plasma and added to human or murine MLC and mitogen-stimulated lymphocyte cultures grown in the presence of complement-inactivated serum. Read-outs were cell proliferation, lymphokine production and development of T cell-mediated cytotoxicity. We found that addition of C1-inh to MLC and mitogen- exposed murine and human lymphocyte cultures inhibited proliferation, the development of allospecific cytotoxic activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12 and IFN-gamma. These data clearly demonstrate a regulatory function of C1-inh on T cell- mediated immune functions.      

Apolipoprotein D is down-regulated during malignant transformation of neurofibromas

Apolipoprotein D (apoD) expression was studied in nonneoplastic peripheral nerve, neurofibromas (NFs), and malignant peripheral nerve sheath tumors (MPNSTs) by quantitative polymerase chain reaction, in situ hybridization, and immunohistochemistry. Multiplex quantitative polymerase chain reaction for messenger RNA was performed on a series of formalin-fixed and paraffin-embedded specimens that included 9 MPNSTs, 12 NFs, and 4 normal peripheral nerves. The average apoD expression was 108-fold decreased (DeltaCt = -7.3) in the MPNSTs compared with the NFs (P < .05). ApoD expression levels were 3.0-fold elevated (DeltaCt = 1.7) in the NFs compared with nonneoplastic peripheral nerve (P < .05). In situ hybridization for apoD RNA was performed on a separate series of 10 cases in which each microscopic section included both MPNST and the NF from which it arose. These studies confirmed elevated apoD expression in NFs compared with MPNSTs and demonstrated that this expression was variable among individual cells within the NFs. Differential expression by immunohistochemistry could only be demonstrated in selected areas, most likely because apoD protein is a small molecule that is secreted out of the cell into the extracellular space and plasma. ApoD expression initially increases a small amount with the formation of NFs from nonneoplastic peripheral nerve and subsequently decreases markedly as NFs transform into MPNSTs. This expression pattern may serve as a marker for cell cycle inhibition during peripheral nerve tumorigenesis.     

Human mini-chromosomes in mouse embryonal stem cells

We have introduced human mini-chromosomes of 4 Mb and approximately 15 Mb in size into mouse embryonal stem cells. Although these human mini- chromosomes are stable in hamster and chicken cells, they re-arrange or segregate aberrantly in the embryonal stem cells and are rapidly lost in the absence of selection. However, one of the mini-chromosomes re- arranged, acquired mouse centromeric sequences and was then stably maintained for at least 60 population doublings in culture. This mini- chromosome, which is 4 Mb in size, is a candidate for a mouse germ line chromosome vector.      

Determination of the parent of origin in nine cases of prenatally detected chromosome aberrations found after intracytoplasmic sperm injection

Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.