Plasma tumor necrosis factor and mortality in critically ill septic patients

Tumor necrosis factor (TNF) cachectin has been implicated as an important host mediator responsible for shock and multiple organ failure (MOF) observed during sepsis. Using a sensitive enzyme-linked immunosorbent assay, we measured plasma TNF levels in 43 septic patients suffering from a broad range of diseases. Measurements were taken on the day that sepsis was diagnosed. Eleven patients had detectable TNF plasma levels ranging from 10 to 100 pg/ml (TNF-positive group); in 32 patients circulating TNF could not be detected (TNF-negative group). The groups did not differ significantly as to age, underlying disease, percentage positive bacteremia and bacteriologic profile, sepsis score, and extent of MOF. Eight (73%) of 11 TNF-positive patients died from sepsis during ICU stay, vs. 11 (34%) of 32 TNF-negative patients (p less than .05). This study demonstrates that sepsis is accompanied by detectable circulating TNF in 25% of the cases, and for these patients mortality is twice that for comparable TNF-negative patients.     

Parotidectomy for parotid tumours: 19-year experience from The Netherlands.

A total of 150 patients were treated for parotid tumours over a period of 19 years. In 94 per cent superficial or total parotidectomy was performed. Histological diagnosis of the resected specimen revealed pleomorphic adenoma in 92 patients (61 per cent), Whartin's tumour in 30 (20 per cent), various benign neoplasms in 11 (7 per cent) and malignant tumour in 17 (11 per cent). After a mean follow-up of 7.7 years, no recurrence of a benign tumour was seen. Malignant tumours recurred in five patients. Permanent partial facial paralysis was seen in 4 per cent of patients after surgery for benign lesions. Frey's syndrome was observed in 43 per cent of patients, and was not prevented by resection of the auriculotemporal nerve.     

Development of a monoclonal antibody specific for beta/A4 amyloid in Alzheimer's disease brain for application to in vivo imaging of amyloid angiopathy.

We evaluated the efficacy of murine monoclonal antibodies (Mabs) targeted to beta/A4 amyloid for development of procedures for the in vivo identification of amyloid angiopathy (AA) in Alzheimer's disease (AD). Mabs to beta/A4 amyloid were prepared and screened for effectiveness in visualizing AA and senile plaques in postmortem AD brain sections. They were assessed again after enzymatic cleavage to produce Fab fragments and after labeling with 99mTc using a diamide dimercaptide ligand system. Modified and radiolabeled Fab fragments retained activity and specificity towards amyloid-laden blood vessels and senile plaques. A highly specific murine Mab, 10H3, was identified and characterized that fulfills criteria necessary for the development of a diagnostic imaging agent. Expansion and adaptation of these strategies may provide the methods and materials for the noninvasive analysis of AA in living patients, and permit assessment of the contribution of AA to the clinical and pathological features of AD.     

Multiple genetic alterations in malignant metastatic insulinomas

Proto-oncogenes, growth factors/receptors, and tumour suppressor genes were analysed in malignant metastatic insulinomas. Normal pancreas showed only a moderate immunoreaction for c-myc proto-oncogene and a strong reaction for insulin. Benign insulinomas were slightly or moderately positive for transforming growth factor a (TGFα), weakly positive for epidermal growth factor receptor (EGF-R), and strongly positive for c-myc and insulin. In malignant insulinomas, besides a strong immunoreaction for c-myc and TGFα, activation of c-K-ras and overexpression of p53 protein were found. Insulin reaction was moderate or strong. Three out of six malignant insulinomas displayed a c-K-ras point mutation at codon 12. All mutations were guanine to cytosine transversion, resulting in amino acid substitution, glycine to arginine. Mutations were present in metastatic insulinomas only. Patients with mutated c-K-ras oncogene had overexpression of p53 protein as well as c-myc and TGFα overexpression. Our results support the view that malignant progression is a consequence of more than one genetic lesion and suggest that activation of myc, TGFα, and ras genesα plays a role in a multistep process of tumour progression, perhaps serving as an initiating event.     

Use of a group-reactive and other monoclonal antibodies in an enzyme immunodot assay for identification and presumptive serotyping of aquatic birnaviruses.

A panel of monoclonal antibodies (MAbs) was prepared and used to develop an enzyme immunodot assay for the rapid identification and presumptive serotyping of aquatic birnaviruses. Comparison of the reaction patterns of these MAbs with representative virus isolates indicated that one MAb recognizes a serogroup-reactive epitope and can therefore be used for identification of all serogroup A aquatic birnaviruses, the predominant serotype worldwide. Other MAbs exhibited more restrictive specificities, permitting the presumptive serotyping of viruses of the three recognized serotypes and the identification of some individual strains. This assay, in which MAbs are used, is more efficient in terms of time, cost, and case of performance and provides significant advantages in specificity and standardization compared with currently used tests.     

Release of [(3)H]-L-glutamate by stimulation of nicotinic acetylcholine receptors in rat cerebellar slices

This is a neurochemical study which shows that nicotine acting through alpha7-containing nicotinic acetylcholine receptors promotes the release of [(3)H]-glutamate from rat cerebellar slices. Release evoked by half maximal concentration of nicotine (100 microM) was blocked by alpha-bungarotoxin and in a calcium-free medium, suggesting an effect mediated by an alpha7 receptor. Dihydro-beta-erythroidine and mecamylamine were effective only at very high concentrations, excluding the participation of heteromeric receptors. The effect of nicotine was partially blocked by inhibitors of glutamatergic receptors DL-2-amino-5-phosphonovaleric acid and 6-cyano-7-nitroquinoxaline-2,3-dione, indicating a glutamate-induced glutamate release. Nicotine-evoked response was dependent on activation of tetrodotoxin sensitive sodium channels. Therefore, here we show that glutamate released by stimulation of alpha7-containing nicotinic receptors, located preterminal and/or postsynaptically, evokes a further glutamate release in adult rat cerebellar slices.     

Immunomodulatory role of endogenous interleukin-18 in gamma interferon-mediated resolution of replicative Legionella pneumophila lung infection

The in vivo role of endogenous interleukin-18 (IL-18) in modulating gamma interferon (IFN-gamma)-mediated resolution of replicative Legionella pneumophila lung infection was assessed using a murine model of Legionnaires' disease. Intratracheal inoculation of A/J mice with virulent bacteria (10(6) L. pneumophila organisms per mouse) resulted in induction of IL-18 protein in bronchoalveolar lavage fluid (BALF) and intrapulmonary expression of IL-18 mRNA. Real-time quantitative RT-PCR analysis of infected lung tissue demonstrated that induction of IL-18 in BALF preceded induction of IL-12 and IFN-gamma mRNAs in the lung. Blocking intrapulmonary IL-18 activity by administration of a monoclonal antibody (MAb) to the IL-18 receptor (anti-IL-18R MAb) prior to L. pneumophila infection inhibited induction of intrapulmonary IFN-gamma production but did not significantly alter resolution of replicative L. pneumophila lung infection. In contrast, blocking endogenous IL-12 activity by administration of anti-IL-12 MAb) alone or in combination with anti-IL-18R MAb inhibited induction of intrapulmonary IFN-gamma and resulted in enhanced intrapulmonary growth of the bacteria within 5 days postinfection. Taken together, these results demonstrate that IL-18 plays a key role in modulating induction of IFN-gamma in the lung in response to L. pneumophila and that together with IL-12, IL-18 regulates intrapulmonary growth of the bacteria.     

ONCOPROTEINS AND TUMOR SUPPRESSOR PROTEINS IN CONGENITAL SACROCOCCYGEAL TERATOMAS

Congenital sacrococcygeal teratoma SCT is the most common germ cell tumor of infancy and childhood with a female preponderance. Most SCTs are diagnosed at birth, are benign, and consist of fully differentiated, mature tissues. Tumorigenesis of SCTs remains poorly understood. Almost nothing is known about possible oncogene activation or tumor suppressor inactivation in these rare tumors. We describe the presence of various oncoproteins and tumor suppressor proteins in eight cases of congenital SCT. The following oncogenes were examined: ras family c-H-, c-N-, and c-K-ras , early genes fos, jun , and tumor suppressor genes p53 and nm23-H-1 . There was no relationship between the intensity of expression of these oncoproteins and tumor suppressor genes and the following parameters: tumor size, age, and survival of the patients. We did not observe any difference, however, between the expression of the examined oncogenes and tumor suppressor genes nm23 and p53 in immature and mature teratomas. Our findings suggest that the ras family of oncogenes, fos and jun oncogenes, and nm23 and p53 tumor suppressor genes are present in congenital SCT, indicating a possible role in genesis and development of these tumors.