CT-guided percutaneous fibrin glue therapy of cerebrospinal fluid leaks in the spine after surgery.

OBJECTIVE: The objective of this study is to assess CT-guided percutaneous injection of fibrin glue for the management of cerebrospinal fluid leaks within the spine. CONCLUSION: Percutaneous CT-guided placement of fibrin glue can provide a treatment option for postoperative cerebrospinal fluid leaks, potentially allowing a major surgical procedure to be avoided. However, the complication of aseptic meningitis may occasionally result from this procedure.

Meningioma in four patients with human immunodeficiency virus infection.

We describe four patients infected with the human immunodeficiency virus (HIV) who had development of meningiomas. In contrast to those in the general population who have meningiomas, all our patients were young men; the mean age was 40 years (range, 32 to 50). Their risk behavior for HIV was homosexuality (three patients) and intravenous drug use (one patient). The CD4+ cell count in each of the three homosexual men was less than 50/microL and was 280/microL in the drug user. Imaging studies showed enhancing lesions in three of the patients. Although each of these meningiomas could have occurred in otherwise normal young to middle-aged men, we speculate that the meningiomas may have grown in these HIV-infected hosts because of either loss of immune function or dysregulation of cytokines.

Percutaneous fibrin glue therapy of meningeal cysts of the sacral spine.

OBJECTIVE: We assessed CT-guided percutaneous injection of fibrin glue to manage meningeal cysts of the sacral spine in patients with back pain. CONCLUSION: All patients experienced resolution or marked improvement of symptoms for as long as 23 months after fibrin glue therapy. No patients experienced recurrence of symptoms during the follow-up interval. Percutaneous CT-guided fibrin glue therapy for sacral meningeal cysts may be a more definitive therapy than repetitive cyst aspiration.

Postoperative cerebrospinal fluid leaks of the lumbosacral spine: management with percutaneous fibrin glue.

PURPOSE: To assess CT-guided injection of fibrin glue for the management of lumbosacral cerebrospinal fluid (CSF) leaks. METHODS: Six consecutive patients with postoperative CSF leaks were treated after CSF aspiration under CT guidance. A solution of cryoprecipitate was simultaneously injected with a 10% calcium chloride solution containing 2000 units of thrombin per milliliter. In one patient, 0.5 mL of iopamidol was added to the calcium chloride/thrombin mixture before injection. Placement of the fibrin glue aggregate was confirmed by CT imaging. To determine outcomes we reviewed the patients' records, postprocedure imaging studies, and physical findings, and we interviewed the patients directly. RESULTS: In three patients with postoperative CSF leaks, symptoms resolved after treatment. Despite imaging evidence of successful plug deployment, two other patients still had severe symptoms, and they underwent surgery after 2 and 18 hours, respectively. One patient had a continued CSF leak and a headache after 12 hours; follow-up surgery repaired an unsuspected dural tear just distal to the site of original surgery underneath the lamina and not covered by the fibrin glue. After one of the successful procedures, the patient had a fever and a headache, probably because of aseptic meningitis, which resolved after 2 days. CONCLUSION: Percutaneous CT-guided placement of fibrin glue may provide nonsurgical treatment for postoperative CSF leaks, potentially avoiding a major and technically difficult surgical procedure.

Percutaneous Therapy of a Post-surgical Suboccipital Cerebrospinal Fluid Fistula with Fibrin Glue.

SUMMARY: The successful therapy of a suboccipital cerebrospinal fluid fistula by the percutaneous introduction of fibrin glue under computed tomographic guidance is described.

Acute and chronic exposure of Dunaliella salina and Chlamydomonas bullosa to copper and cadmium: effects on growth.

Effective copper and cadmium concentrations which limited the growth of two chlorophytes by 50%, EC(50)s, after 96 h of static exposure were determined. EC(50)s were 5.94 microM copper and 4.55 microM cadmium for Dunaliella salina, and 0.78 microM copper and 0.025 microM cadmium for Chlamydomonas bullosa. The relationship of the two cations was synergistic towards the growth of both species. Chronic exposure to 4.5 x 10(-6) microM cadmium or 4.9 x 10(-4) microM copper increased the sensitivity of C. bullosa by 26% and 29% towards cadmium and copper, respectively. Changes in co-tolerance were not observed. Cd-treated D. salina was 50% more tolerant towards this cation, whereas Cu-treated cultures showed extreme sensitivity towards copper and "co-sensitivity" towards cadmium. Furthermore, the phylogenetic hypothesis, predictive of toxic response, failed to hold at the familial level.

Acute and chronic exposure of Dunaliella salina and Chlamydomonas bullosa to copper and cadmium: effects of ultrastructure.

The ultrastructural changes of Dunaliella salina and Chlamydomonas bullosa taking place after short term exposure to established copper and/or cadmium EC(50) or exposure to low levels of these cations for 8 months were examined. Cadmium had a greater impact on the ultrastructure of these species than copper. Metal stress affected a variety of cellular parameters including total cell volume, pyrenoid, nucleus, starch granules, polyphosphate bodies, lipids, vacuoles, cell wall, and periplasmalemmal space. The measurements of these cellular parameters used the technique of electron microscopic stereoscopic morphometry. Differences resulting from acute vs. chronic exposure to the cations are documented.

A prospective evaluation of radiologic criteria for head injury patients in a community emergency department.

Several management strategies for radiographic evaluation of head-injury patients have been developed, most are based on retrospective analysis. The study attempted to prospectively evaluate the previously published Masters' criteria defining low-, medium-, and high-yield patients. A community hospital emergency department with a low prevalence of serious head injury was studied, and 1,000 consecutive patients 2 years of age presenting with historical or physical evidence of blunt head trauma were asked to participate; 967 consented. The patients were categorized by staff emergency physicians as low-, moderate-, and high-yield for intracranial injury on the basis of their initial history and physical examination. These categories guided imaging decisions in accordance with the guidelines of Masters. The patients were evaluated 6 weeks later by multiple questionnaire and/or telephone calls to determine whether or not undiagnosed head injuries had been missed. The 967 patients initially evaluated were classified according to their risk of intracranial injury as follows: 886 at low risk, 78 at moderate risk and 3 at high risk. Complete follow-up data were available for 895 of these patients (93%). Of the 895, 71 patients (7.9%) did report receiving follow-up medical care for their head injury; none had evidence of missed intracranial injury requiring intervention. Therefore, it can be inferred with a 95% confidence interval that 0.4% or less of patients who were diagnosed as not having intracranial injuries requiring intervention may actually have such injuries. The application of Masters' management strategy in low-risk populations permits clinicians to safely reduce the number of radiographs ordered for patients with head injury.

The growth response of the green alga Chlorella vulgaris to combined divalent cation exposure.

Using the growth response of the green alga Chlorella vulgaris as a model system, the effects of combinations of the environmentally active cations Cd, Co, and Cu were evaluated. The 96-h static EC50 for these cations to C. vulgaris were, respectively, 0.89 microM, 9.0 microM, and 2.8 microM, yielding a toxicity series such that Cd > Cu > Co. The cation combinations of Cd + Cu, and Cu + Co acted synergistically, while Cd + Co, and the tri-metallic combination Cd + Cu + Co resulted in antagonistic interactions. Examination of these toxic combinations at 24, 48, 72, and 96 h indicate that the cellular response is not a uniform one. Failure of energy dispersive X-ray spectrophotometric analysis to demonstrate any intracellular incorporation of these cations (except for a weak cytoplasmic Cu peak at the 8.0 KEV position) suggests that the toxic actions of these cations at EC50 concentrations are exerted at the level of the plasma membrane.

Ultrastructural changes in Dunaliella minuta following acute and chronic exposure to copper and cadmium.

The ultrastructural changes taking place after short-term acute exposure to copper, cadmium and a combination of the two metals were examined. Additionally, the effects of long-term (8 months) exposure to ambient concentrations of these metals were investigated. Exposure to 0.34 microM cadmium affected the photosynthetic potential of this alga, by reducing the relative volume of the chloroplast by 23.27%. It also led to 74.6% increase in the relative volume of starch granules. Cells challenged with 0.34 microM cadmium and 7.57 microM copper had 33.49% larger volumes than controls, and their relative lipid volumes increased by 170%. In contrast, the relative volume of their pyrenoids decreased by 41.46%. Similar results were obtained after chronic exposure to 4.9 x 10(-4) microM copper with the relative volume of the pyrenoid being 28% smaller than the controls.

Evidence for molecular subtypes of HIV-associated lymphoma: division into peripheral monoclonal, polyclonal and central nervous system lymphoma.

The pathogenesis of the HIV-associated lymphomas is not well understood. In order to begin characterizing this class of lymphoma, we initiated a molecular genetic study of DNA extracted from 31 diagnostic biopsy specimens from patients diagnosed with AIDS-associated non-Hodgkin's lymphoma. Analysis of 25 peripheral lymphomas showed that 14 were monoclonal B-cell processes, while 11 appeared to be of polyclonal origin. Five of the 14 monoclonal lymphomas were found to have rearrangements of the c-myc gene. Epstein-Barr virus (EBV) genomes were found in seven out of 14 monoclonal samples, but only two out of nine polyclonal samples. The six primary central nervous system (CNS) lymphoma samples were more homogeneous than the peripheral samples and all were monoclonal, positive for EBV and lacked detectable c-myc gene rearrangements. This study allows us to subdivide the HIV-associated lymphomas into three major molecular subtypes: (1) monoclonal B-cell process frequently associated with c-myc rearrangement or detectable EBV genomes, (2) polyclonal B-cell process typically without evidence of EBV, and (3) monoclonal primary CNS process associated with EBV genomes and lacking detectable c-myc rearrangement.

The effects of pH on the growth of Chlorella vulgaris and its interactions with cadmium toxicity.

The effects of pH alone, and in combination with exposure to 0.89 microM cadmium, on the growth response of the green alga Chlorella vulgaris were evaluated. Acidic (3.0-6.2) and alkaline (8.3-9.0) pH values retarded the growth of this alga. Optimal growth occurred when the pH of the medium was adjusted to values of 7.5 and 8.0. When the cells were exposed to pH adjusted medium plus the presence of 0.89 microM Cd, a value known to reduce population growth by 50% at the control pH of 6.9, the affects were additive at the acidic (3.0-5.0) pH ranges. At alkaline pH values of 8.3-9.0 all toxicity responses could be explained by pH adjustment alone, indicating that additional cadmium toxicity was absent. At pH values of 7.5 and 8.0, cadmium toxicity was mitigated against, and resultant growth at pH 8.0 was at the same enhanced rate as this pH without cadmium.

The toxic action and interactions of copper and cadmium to the marine alga Dunaliella minuta, in both acute and chronic exposure.

The effective concentrations of copper and cadmium which reduced the population growth of Dunaliella minuta by 50% after 96 h of static exposure, were determined to be 7.57 microM Cu and 0.34 microM Cd. Short-term static exposure to both metals indicated that their combined action is antagonistic with respect to growth of this chlorophyte. Additionally, long-term exposure to low levels of Cu or Cd led to the acquisition of tolerance towards Cu and Cd, respectively, and co-tolerance towards Cu.

Primary central nervous system lymphomas: natural history and response to radiation therapy in 55 patients with acquired immunodeficiency syndrome.

The incidence of primary central nervous system (CNS) lymphoma has increased rapidly in patients with acquired immunodeficiency syndrome (AIDS) and is predicted to exceed 1800 cases annually by 1991. To characterize the natural history and response to radiation therapy (RT) of these lesions, the authors have reviewed the clinical histories of 55 AIDS patients with biopsy-proven primary CNS lymphomas. The tumors responded both clinically and radiologically to whole-brain RT consisting of 4000 rad in 267-rad fractions over 3 weeks or an equivalent neuroret dose. The mean duration of survival from the appearance of symptoms consistent with the mass lesion was significantly greater in patients who received RT than in those who did not (42 vs. 134 days, p less than 0.5; median 27 vs. 119 days). Autopsy findings showed that patients who did not receive RT died from tumor progression, whereas those who completed RT died of opportunistic infections. Patients with AIDS who are suspected of having primary CNS lymphoma should therefore immediately undergo biopsy and, if the diagnosis is confirmed, whole-brain RT. With early diagnosis and treatment, these tumors respond to, and patients benefit from, RT. Survival of such patients may in future be prolonged by more effective treatments for systemic opportunistic infections.

A morphometric and X-ray energy dispersive approach to monitoring pH-altered cadmium toxicity in Anabaena flos-aquae.

Cadmium toxicity and uptake as influenced by different pH values have been studied in the freshwater cyanobacterium Anabaena flos-aquae, using the techniques of morphometric analysis, x-ray energy dispersive analysis and atomic absorption spectrophotometry. A general reduction in cell dimension, thylakoid surface area, number and volume of polyhedral bodies, polyphosphate bodies, cyanophycin granules, lipid bodies, membrane limited crystalline inclusions, volume and number of wall layers and mesosomes was observed. These reductions were more pronounced in both acidic and alkaline medium than at pH 7.2. At 0.12 microM Cd, the uptake increased with alkaline pH values, and uptake was greater at pH 7.2 than at either acid or alkaline pHs. Lysis of cell wall at 1.18 microM Cd showed the following decreasing trend: pH 4.0 greater than pH 5.5 greater than pH 10.0 greater than pH 9.0 greater than pH 7.2. There was a total loss of lipid bodies at 1.18 microM Cd at all pH values listed. It is suggested that these techniques can be successfully employed for bioassay studies of metal toxicity to algae. In particular, cell wall lysis and loss of lipids by algae are good indicators of pH effects and metal toxicity in the aquatic ecosystem.

Selecting a screening mammography facility.

Breast cancer is the second most common cause of cancer mortality in women. During the past 20 years, two major mammography screening programs have demonstrated reduced mortality in patients over age 50. Mammography can be safe and effective. Physicians should recommend mammographic facilities with trained and experienced personnel, dedicated mammographic and processing equipment, and quality control procedures.

Inoculation of simian virus 40 into pregnant hamsters can induce tumors in offspring.

Inoculation of 10(7) plaque-forming units of Simian virus 40 (SV40) into pregnant hamsters, a host in whom the virus cannot replicate, during the 8th or 12th day of gestation, produced subcutaneous tumors in offspring 4 to 10 months after birth. These tumors contained SV40 T antigen, and SV40 DNA was integrated into tumor cell DNA. Lower doses of virus or the same amount inoculated later in gestation had no effect. The same tumorogenic dose of virus inoculated at day 4 of gestation was associated with developmental delay and early death of offspring, but did not induce tumors. None of the inoculated mothers showed any effect of the virus. These findings indicate that SV40 can somehow cross the placenta of a nonpermissive host, the hamster, and induce tumors in susceptible offspring.

Examination of the utility of the rat as an animal model for human anticoagulation.

The feasibility of employing the rat as an experimental model for investigation of full-dose heparin anticoagulation was assessed. Striking similarities were found to exist between rats and humans regarding baseline-activated partial thromboplastin time (APTT) values, and dosage per kilogram of heparin required to produce an APTT value of 1 1/2-3 times normal, the clinical definition of full-dose heparinization. Based upon these similarities, it appears that the rat can effectively serve as an experimental model for investigating the effects of heparin in humans.