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INTRODUCTION: A novel referral pathway for exhibited breast symptom (EBS) referrals to manage increasing referrals of urgent suspected cancer (USC) was implemented in our trust. We report on the safety and effect on compliance with the 2-week-wait rule (2WW). METHODS: A single-centre longitudinal observational study included all patients referred to a UK breast unit during 13 May 2019 to 27 March 2020 (period 1) and 8 February 2021 to 31 January 2022 (period 2). USC referrals were assessed in a one-stop clinic (red flag clinic [RFC]); EBS referrals were assessed in a new clinic in which clinical evaluation was performed and imaging occurred subsequently (blue flag clinic [BFC]). Patients were followed up to determine the symptomatic interval cancer rate. RESULTS: There were 9,695 referrals; 1,655 referrals (17%) were assessed in the BFC after 63 exclusions. Some 95.9% of patients had a benign clinical examination (P1/P2), 80.1% had imaging (mammogram or ultrasound) and 4% had a tissue biopsy. In total, 16/1,655 (0.97%) BFC patients and 510/7,977 (8.2%) RFC patients were diagnosed with breast cancer (breast cancer detection rate). Some 1,631 patients (with 1,639 referrals) were discharged and followed up for a median of 17 months (interquartile range 12-32) with one subsequent cancer diagnosis (symptomatic interval cancer rate, 0.06%). Implementation of the BFC pathway increased 3-month average trust performance of USC referrals with 2WW standard from 8.5% to 98.7% (period 1) and from 30% to 66% (period 2). CONCLUSIONS: The BFC pathway for EBS patients is safe and implementation led to improvement against the 2WW target for USC referrals, ensuring resources are prioritised to patients with the highest likelihood of breast cancer.
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BACKGROUND: Monoclonal antibodies, such as cemiplimab and pembrolizumab, against the programmed death receptor (PD)-1 have become the current standard of care and first-line treatment of advanced cutaneous squamous cell carcinoma (cSCC), proving remarkable clinical benefit and acceptable safety. OBJECTIVES: To assess efficacy and safety of the anti-PD-1 antibody nivolumab in patients with locally advanced and metastatic cSCC. METHODS: Patients received open-label nivolumab 240 mg intravenously every 2 weeks for up to 24 months. Patients with concomitant haematological malignancies (CHMs), either non-progressing or stable under active therapy, were eligible for inclusion. RESULTS: Of 31 patients with a median age of 80 years, 22.6% of patients achieved an investigator assessed complete response, resulting in an objective response rate (ORR) of 61.3% and a disease control rate (DCR) of 64.5%. Progression-free survival (PFS) was 11.1 months, and the median overall survival (OS) was not reached after 24 weeks of therapy. Median follow-up was 23.82 months. Subgroup analysis of the CHM cohort (n = 11; 35%) revealed an ORR of 45.5%, a DCR of 54.5%, a median PFS of 10.9 months, and median OS of 20.7 months. Treatment related adverse events were reported in 58.1% of all patients (19.4% grade 3, the remaining grade 1 or 2). PD-L1 expression and CD-8+ T-cell infiltration did not significantly correlate with clinical response, although a trend towards a shorter PFS of 5.6 months was observed with PD-L1 negativity and low CD8+ intratumoral infiltration. CONCLUSION: This study demonstrated robust clinical efficacy of nivolumab in patients with locally advanced and metastatic cSCCs and a tolerability comparable to data of other anti-PD-1 antibodies. Favourable outcomes were obtained despite involving the oldest hitherto reported study cohort for anti-PD-1 antibodies and a significant proportion of CHM patients prone to high risk tumours and an aggressive course otherwise typically excluded from clinical trials.
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Carcinoma de Células Escamosas , Neoplasias Hematológicas , Neoplasias Cutâneas , Humanos , Idoso de 80 Anos ou mais , Nivolumabe/uso terapêutico , Nivolumabe/efeitos adversos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/induzido quimicamente , Antígeno B7-H1 , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/induzido quimicamenteRESUMO
INTRODUCTION: Wire guided localisation (WGL) is the standard localisation technique for impalpable breast lesions. Radio-guided occult lesion localisation (ROLL) has been proposed as an alternative. We have been performing ROLL for therapeutic wide local excisions (WLE) and diagnostic excision biopsies (DEB) for the last 15 years. We present the largest reported consecutive series of ROLL excisions to date. PATIENTS AND METHODS: One thousand thirty nine consecutive patients who underwent ROLL for impalpable breast lesions were identified from a prospectively collected database. 673 patients underwent WLE and 366 patients underwent DEB. Data were analysed from proformas completed at the time of the procedure by the radiologist and operating surgeon. These data were supplemented with an analysis of patient electronic records including specimen radiograph and histopathology reports. RESULTS: 99.1% of ROLL WLE revealed histological diagnoses of invasive cancer or DCIS. 98.7% of radiological abnormalities were identified on WLE post-excision radiographs (97.5% following DEB). Complete excision was recorded in 79.0% of the WLE patients following histological evaluation. 31.7% of DEB cases were pathologically upgraded to a malignant diagnosis. The presence of microcalcification, preoperative underestimation of the lesion size and symptomatic referral predisposed to incomplete excision status. DISCUSSION: ROLL is a safe and effective technique to localise impalpable breast lesions. In addition ROLL has potential technical and logistic advantages over WGL.
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Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mamografia , Mastectomia Segmentar , Pessoa de Meia-Idade , Invasividade Neoplásica , Palpação , Estudos Prospectivos , Radioisótopos , Biópsia de Linfonodo Sentinela , Agregado de Albumina Marcado com Tecnécio Tc 99m , Ultrassonografia MamáriaRESUMO
Glass-ceramic nanocomposites comprising GdBr3/CeBr3 loaded sodium-aluminosilicate glasses in which scintillating crystallites are precipitated in situ from a host glass matrix were studied. This materials system shows promise as an alternative to single-crystal scintillators, with potential to be fabricated into a wide variety of sizes, shapes, and compositions. Batch compositions containing 15-18 mol. % GdBr3 and 3-4 mol. % CeBr3 were prepared and analyzed for photoluminescent light yield. Light yield peaked with rare-earth content of 15 mol. % GdBr3 and 4 mol. % CeBr3. Preliminary ceramization studies on this composition found that the precipitated phase more closely matched a Gd2O3-CeO2 mixture rather than the GdBr3(Ce) that was targeted.
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A glass wafer that contains cerium-activated gadolinium-based scintillator has been tested as a nuclear radiation monitor. The detector is prepared by mixing powdered gadolinium and cerium (3+) bromides with alumina, silica, and lithium fluoride, melting the mixture at 1,400°C, and then quenching and annealing the glass. The resulting clear glass matrix emits stimulated blue light that can be collected by a conventional photomultiplier tube. Spectral analysis of radionuclides with this detector shows the energy peaks for alpha particles, the energy continuum for beta particles, the Compton continuum and full-energy peaks for gamma rays, and an energy continuum with specific reaction-product peaks for neutrons. Energy resolution for the 5.5-MeV alpha particle and 0.662-MeV gamma-ray peaks is about 20%. This resolution, although threefold poorer than for single-crystal NaI(Tl) scintillators, contributes to radionuclide identification and quantification. Application of this detector to radiation monitoring is proposed, as well as approaches for improving light collection and energy resolution that will facilitate radionuclide identification and monitoring, especially for alpha particles, beta particles, and low-energy gamma rays.
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Brometos/química , Cério/química , Gadolínio/química , Vidro/química , Monitoramento de Radiação , Contagem de Cintilação , Partículas alfa , Óxido de Alumínio/química , Partículas beta , Fluoretos/química , Raios gama , Compostos de Lítio/química , Nêutrons , Dióxido de Silício/químicaRESUMO
Laparoscopic pancreatic procedures are still at the stage of evaluation with regard to their indications and the technical variation used. Laparoscopic pancreatic surgery is currently used for staging malignant pancreatic tumours, for the resection of benign pancreatic tumours and for the occasional management of inflammatory disorders of the pancreas. Insulinomas are rare tumours with incidence per year of 0.1-0.4 per 100,000. Ist Surgical clinic, IIIrd Internal clinic and Radiological clinic are cooperating since 1971. On the list of IIIrd Internal clinic are 80 patients with insulinoma. Since 1971 at Ist Surgical Clinic 66 patients have been operated. In our article are diagnostic and therapeutic problems discussed. Laparoscopic pancreatic procedures are still at an evaluation stage regard to their indications and techniques. Authors give report about first experience with successful laparoscopic enucleation of insulinoma in case 83 year old woman (Fig. 3, 4). The operative time was 90 min. Drainage is necessary. CT guided drain in cavity of seroma is shown (Fig. 5).
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Hiperinsulinismo/diagnóstico , Hiperinsulinismo/cirurgia , Insulinoma/cirurgia , Laparoscopia , Neoplasias Pancreáticas/cirurgia , Humanos , Hiperinsulinismo/etiologia , Insulinoma/complicações , Pancreatectomia/métodos , Neoplasias Pancreáticas/complicaçõesRESUMO
The effect of low dose T-2 toxin was investigated in chicken, duck and goose. The purpose of the present study was to investigate the effect of T-2 toxin on the lipid peroxidation and on the activity of glutathione redox system (amount of reduced and oxidised glutathione and the activity of glutathione peroxidase) in blood and liver. The treatment lasted days and two samples were taken, first at the time of lowest feed intake and second when the intake was the same as the control. It was found, that lipid per oxidation as detected by the amount of malondialdehyde increased in all of the species and tissues but the changes varied by species. The most sensitive species was goose followed by duck and chicken, and the most sensitive tissue was the liver followed by blood plasma and red blood cells.
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Antioxidantes/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Aves Domésticas/metabolismo , Toxina T-2/toxicidade , Animais , Galinhas , Patos , Gansos , Glutationa/sangue , Glutationa/metabolismo , Dissulfeto de Glutationa/sangue , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/sangue , Glutationa Peroxidase/metabolismo , Fígado/efeitos dos fármacos , Aves Domésticas/sangue , Valores de ReferênciaRESUMO
60% of relapses of rectal cancer after abdominoperineal resection occurs at the site of the surgical intervention. Early detection of these recurrent tumours is vital. Among the up-to-date imaging systems CT is the most sensitive method in diagnosis of pelvic tumours. Despite the accurate imaging diagnosis the nature of lesions remains sometimes ambiguous. 11 CT guided biopsies and 2 punctures were performed because of suspected local recurrence or abscess. As a result of biopsies, local recurrence was histologically proven in 6 cases, fibrosis in 4, inflammatory disease in 1. Both punctures revealed the cytological diagnosis of abscess. There were no complications. The interventions were carried out in prone position through the greater sciatic foramen. In the knowledge of the exact anatomy of this region, the procedure can be performed safely by CT guidance and a correct diagnosis can be achieved.
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Recidiva Local de Neoplasia/cirurgia , Neoplasias Retais/cirurgia , Abscesso/diagnóstico , Abscesso/patologia , Abscesso/cirurgia , Adulto , Idoso , Biópsia por Agulha , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Diafragma da Pelve/patologia , Diafragma da Pelve/cirurgia , Complicações Pós-Operatórias/diagnóstico , Neoplasias Retais/patologia , Reoperação , Tomografia Computadorizada por Raios XRESUMO
New Zealand White rabbits (6 males and 6 females) were fed a diet of high lipid peroxide content (peroxide value: 249.05 meq/kg fat) for 21 days. Twelve rabbits served as controls (peroxide value: 40.3 meq/kg fat). The lipid peroxide loading did not cause clinical signs. The rate of lipid peroxidation, as measured on the basis of thiobarbituric acid reactive substances (TBARS), was significantly (P < 0.05) higher in all of the investigated tissues, in the following order: liver > red blood cells (RBC) > blood plasma. Reduced and oxidised glutathione content was higher in the blood plasma (P < 0.01) and liver (P < 0.001) of rabbits exposed to the peroxide load. Lipid peroxide loading decreased the activity of glutathione peroxidase in the blood plasma, RBC haemolysate and liver and that of glutathione reductase in the liver. The amount of cytochrome P450 (both CO- and metyrapone-reduced) and the activity of cytochrome c (P450) oxidoreductase in the microsomal fraction of the liver homogenate were also lower in the group exposed to lipid peroxide load. Subchronic alimentary lipid peroxide loading in the presence of sufficiently high levels of antioxidants in the complete feed was found to increase the rate of lipid peroxidation and markedly lower the activities of both the glutathione and xenobiotic transforming enzyme systems without causing any clinical signs of toxicity.
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Citocromos/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/farmacologia , Coelhos/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/análise , Citocromos/fisiologia , Dieta/veterinária , Eritrócitos/química , Feminino , Glutationa/fisiologia , Glutationa Peroxidase/sangue , Glutationa Redutase/análise , Glutationa Redutase/sangue , Peroxidação de Lipídeos/fisiologia , Fígado/química , Fígado/enzimologia , Fígado/metabolismo , Masculino , Microssomos Hepáticos/enzimologia , Coelhos/fisiologia , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
Hyperthermia modulated the cytotoxic activities of murine macrophages cocultured with EMT-6 tumor cells, altered the production of the monokines RIF (respiratory inhibition factor) and FeRF (iron-releasing factor) by these effector cells, and perturbed the activities of these monokines against EMT-6 cells. Cytotoxic activities of heated murine macrophages activated by Bacillus Calmette-Guérin were inhibited by heat doses of 40.5 degrees C for greater than or equal to 1 h if heating preceded triggering by the endotoxin lipopolysaccharide; however, cytotoxic activities were better retained if triggering preceded heating by 2 h. Treatment-sequence dependencies were also found in the secretion of some monokines that participate in these macrophage cytotoxic effects. Secretion of both RIF and FeRF by macrophages was slightly augmented or at least better retained if triggering of macrophages occurred several hours before heating for 1 h at 40.5-43 degrees C or for 24 h at 39-40.5 degrees C. If heating was nearly simultaneous with triggering or preceded it by several hours, there was a dose-dependent decrease in monokine secretion. The sensitivity of tumor cell targets to these monokines was also modified by the treatment sequence. When EMT-6 cells were treated with RIF- or FeRF-containing macrophage conditioned supernatants 1 h before heating at 40.5-43 degrees C, the RIF-treated cells became sensitized and the FeRF-treated cells retained better cytotoxic response than if cells had been treated 1 h after heating. Chronic heating for 24 h at 39-40.5 degrees C showed less dependence of tumor cell response on treatment sequence. Similar observations have recently been made in our laboratory for the interaction of tumor necrosis factor cytotoxic pathways with hyperthermia (Klostergaard et al., J. Biol. Response Modif., in press, 1989; Tomasovic et al., Int. J. Hyperthermia, in press, 1989). Those results and the present observations with the monokines RIF and FeRF support our hypothesis that the cytotoxic actions of macrophages and the cytotoxicity of endogenously added monokines can be augmented by appropriately constructed sequences combining hyperthermia with either macrophage priming/triggering or monokine treatment of tumor cells.
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Temperatura Alta , Ativação de Macrófagos , Macrófagos/imunologia , Monocinas/metabolismo , Adenocarcinoma , Animais , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Cromo/metabolismo , Feminino , Ferro/metabolismo , Cinética , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Masculino , Neoplasias Mamárias Experimentais , Camundongos , Camundongos Endogâmicos , Monocinas/imunologia , Mycobacterium bovis/imunologiaRESUMO
Post-operative neurosonography - through calvarial defect. 9 patients were examined by post-operative high resolution real-time ultrasound, using an operative calvarial defect. The findings of 2 patients are analysed in details. The authors have found good agreement with computed tomography, with other imaging methods and pathology as well. They suggest sonographic examination as a first step in the follow-up control of the pathological processes in patients with burr holes.
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Encefalopatias/diagnóstico , Neoplasias Encefálicas/cirurgia , Ultrassonografia/métodos , Adulto , Ependimoma/cirurgia , Feminino , Humanos , Aneurisma Intracraniano/cirurgia , Masculino , Cuidados Pós-OperatóriosRESUMO
Hyperthermia in the therapeutic (greater than or equal to 42-43 degrees C) and febrile (less than or equal to 39-40.5 degrees C) ranges modulated the cytotoxic activities of macrophages cocultured with tumour cells and of the monokine tumour necrosis factor (TNF) against tumour cells. These modulatory interactions had clear treatment-sequence dependencies, and some sequences markedly augmented cytotoxic activities. Heated murine bacillus Calmette-Guerin-activated macrophages retained their cytotoxic activities better in coculture with unheated tumour cells if triggering with the endotoxin lipopolysaccharide preceded 1 h of heating at 42 or 43 degrees C than they did if heating to the same extent was concomitant with, or preceded, triggering. Retention of cytotoxicity in coculture during 24 h of 39 or 40.5 degrees C heating was less dependent on pre-heating triggering. The triggering/heating sequence also had modulatory effects on the secretion by heated macrophages of TNF which is involved in cytotoxic manifestations in coculture. Production of TNF by macrophages heated for 1 h at 40.5-43 degrees C or 24 h at 39 or 40.5 degrees C was augmented 1.5- to 6-fold (depending on the heat dose) when triggering preceded heating, whereas sequences in which heating was concomitant with triggering or preceded triggering were detrimental to TNF secretion. Profound treatment-sequence dependencies were also seen when timing of the addition of recombinant human TNF was varied in relation to the heat treatment of tumour cells. Sensitization of TNF-responsive L-929 and TNF-resistant EMT-6 tumour cells occurred if monokine addition preceded heating, whereas the reverse treatment-sequence reduced or eliminated sensitization. Both tumour cell types were also sensitized to TNF if monokine treatment preceded 24 h heating at 40.5 degrees C. These results support the hypothesis that appropriately constructed sequences for either macrophage priming/triggering or monokine treatment of tumour cells, combined with hyperthermia, could augment the cytotoxic actions of macrophages and the cytotoxicity of endogenously added monokines.
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Temperatura Alta/uso terapêutico , Macrófagos/metabolismo , Células Tumorais Cultivadas/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Animais , Células Cultivadas , Citotoxicidade Imunológica , Ativação de Macrófagos , Macrófagos/imunologia , Camundongos , Mycobacterium bovis/imunologia , Fatores de Tempo , Células Tumorais Cultivadas/imunologia , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Vital dye uptake and postfixation dye assays have recently been used to examine the interaction between short-term (24-48 h) exposures to the monokine, tumor necrosis factor (TNF), and hyperthermic treatments with the finding that synergistic increases in cytotoxicity occurred. However, survival measured by these short-term dye assays is not necessarily closely related to eventual loss of clonogenic capacity. Treatment-induced growth delays, delayed cytotoxic effects, or perturbations of vital dye sequestration mechanisms could result in a different measurement of surviving fraction than given by a clonogenic assay. In this study we directly compared the neutral red vital dye uptake and clonogenic survival assays and confirmed in both assays that TNF-sensitive (L-929) and TNF-resistant (EMT-6) phenotypes show greatly reduced survival when treated with combined recombinant human TNF (1.0-0.0005 micrograms/ml) and hyperthermia (1-2 h at 43 degrees C). Moreover, we confirmed that sensitization of the TNF-resistant EMT-6 cells was largely dependent on monokine treatment before hyperthermia and was reduced by the reverse sequence. The greatest sensitization of TNF-responsive L-929 cells also occurred when TNF treatment preceded heating. These results for clonogenic survival are consistent with the hypothesis that hyperthermia used in combination with TNF in vivo is more cytotoxic than TNF or hyperthermia separately.
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Temperatura Alta , Fator de Necrose Tumoral alfa/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Vermelho Neutro/farmacocinética , Proteínas Recombinantes , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo , Ensaio Tumoral de Célula-TroncoRESUMO
The sonographic diagnosis and surgical treatment of the ependymoblastoma of a 9,5-month old infant is reported. The tumor originated from the posterior scale and caused obstruction in the aquaeductus cerebri and hydrocephalus. The modern radiological diagnosis of tumors in the posterior scale is reviewed.
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Neoplasias Encefálicas/diagnóstico , Ependimoma/diagnóstico , Ultrassonografia , Neoplasias Encefálicas/cirurgia , Fossa Craniana Posterior , Ependimoma/cirurgia , Feminino , Humanos , LactenteRESUMO
Tumor necrosis factor (TNF) production by human peripheral blood monocytes and murine bacillus Calmette-Guerin-activated peritoneal macrophages was strongly influenced by acute hyperthermia. If hyperthermia was administered simultaneously with or preceding lipopolysaccharide triggering, production was severely ablated by 42 degrees and 43 degrees C treatments; however, if triggering preceded heating by at least 90 min, production was either unaffected or markedly enhanced. A somewhat similar pattern was reflected with chronic heating. TNF production by murine macrophages was inhibited with 39 degrees C heating and completely blocked by 40.5 degrees C treatment, if triggering coincided with the initiation of hyperthermia. However, augmentation of production occurred with either of these temperatures if triggering preceded hyperthermia by as little as 90 min. Human monocytes demonstrated greater resistance to the deleterious effects of coincident triggering and heating with respect to TNF secretion than the rodent effectors, but the response was otherwise very similar. The TNF-sensitive phenotype of the L929 cell could be augmented by chronic or acute hyperthermia, markedly so with a 43 degrees C treatment. The TNF-resistant phenotype of the EMT-6 cell could be reversed by chronic heating at 40.5 degrees C, or by acute heating at 43 degrees C, but only if the latter followed TNF treatment. These results reflect important regulatory controls of TNF production and responses in tumor cells which are susceptible to hyperthermia manipulation.
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Temperatura Alta/uso terapêutico , Células Tumorais Cultivadas/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Citotoxicidade Imunológica , Humanos , Técnicas In Vitro , Macrófagos/imunologia , Camundongos , Monócitos/imunologia , Mycobacterium bovis/imunologia , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
The fluctuations in the concentrations of progesterone in peripheral blood of three intact coypus and three coypus after natural mating were investigated for the period of four months. Immediately after mating the concentrations of progesterone are low (1.5-2.4 ng.ml-1), the maximum values reach the peak between the 14th and 15th week of gravidity (12.50-20.72 ng.ml-1), whilst there is almost no change in the intact females. On the last days of gravidity the values of progesterone decrease rapidly and they are very low on the day of parturition (1.0-2.5 ng.ml-1). The concentration of progesterone in the blood plasma of intact females in the test period is low (0.09-3.18 ng.ml-1).
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Prenhez/sangue , Progesterona/sangue , Roedores/sangue , Animais , Feminino , GravidezRESUMO
A surgical approach that offered direct visualization and removal of the hypophysis was evaluated in 17 dogs. Ten of the dogs were euthanatized and used to identify reliable landmarks for the drill site in the basisphenoid bone to expose the hypophysis. The intersphenoidal suture was an accurate landmark in that 1 cm caudal to the intersphenoidal suture was determined to be the precise point for the center of the drill hole. The remaining 7 dogs were hypophysectomized, using this approach. The landmarks were accurate, the surgery had a high degree of safety, and all hypophyses were removed.
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Cães/cirurgia , Hipofisectomia/veterinária , Mandíbula/cirurgia , Animais , Hipofisectomia/métodosRESUMO
Two types of bead-form macroporous carriers based on glycidyl methacrylate with ethylene dimethacrylate copolymers were used for the immobilization of penicillin amidase either directly or after chemical modification. Direct binding through oxirane groups, which is equally efficient at pH 4.2 and 7, is relatively slow and brings about an activity loss at low enzyme concentrations. The most efficient immobilization was achieved on glutaraldehyde-activated amino carrier, irrespective of whether the amino groups were formed by ammonia or 1,6-diaminohexane treatment of the original oxirane carrier. Hydrazine treatment gave lower immobilization yields. The same is true of the azide method independent of the length of the spacer. Most enzyme activity was preserved by coupling the carbodiimide-activated enzyme to the carrier with alkyl or arylamino groups at the end of a longer substituent. Immobilization on diazo-modified carrier gave average results. Rapid immobilization by a lysine-modified phosgene-treated carrier resulted in an activity loss. It is suggested that multipoint and very tight attachment of the enzyme molecule to the matrix decreased the activity. The immobilized activity is quite stable in solution and very stable upon lyophilization with sucrose.