Andrological findings in infertile men with two (biallelic) CFTR mutations: results of a multicentre study in Germany and Austria comprising 71 patients.

STUDY QUESTION: When should cystic fibrosis transmembrane conductance regulator (CFTR) mutation analysis be recommended in infertile men based on andrological findings? SUMMARY ANSWER: CFTR mutation analysis is recommended in all men with unexplained azoospermia in the presence of normal gonadotropin levels. WHAT IS KNOWN ALREADY: While 80-97% of men with congenital bilateral absence of the vas deferens (CBAVD) are thought to carry CFTR mutations, there is uncertainty about the spectrum of clinical and andrological abnormalities in infertile men with bilallelic CFTR mutations. This information is relevant for evidence-based recommendations to couples requesting assisted reproduction. STUDY DESIGN, SIZE, DURATION: We studied the andrological findings of patients with two CFTR mutations who were examined in one of the cooperating fertility centres in Germany and Austria. In the period of January till July 2019, the completed and anonymized data sheets of 78 adult male patients were returned to and analysed by the project leader at the Institute of Human Genetics in Innsbruck, Austria. PARTICIPANTS/MATERIALS, SETTING, METHODS: Minimum study entry criteria were the presence of two (biallelic) CFTR mutations and results of at least one semen analysis. Andrological assessments were undertaken by standardized data sheets and compared with normal reference values. Seventy-one patients were eligible for the study (n = 30, 42% from Germany, n = 26, 37% from Austria, n = 15, 21% other nations). MAIN RESULTS AND THE ROLE OF CHANCE: Gonadotropin levels (FSH, LH) were normal, 22% of patients had reduced testosterone values. Mean right testis volume was 23.38 ml (SD 8.77), mean left testis volume was 22.59 ml (SD 8.68) and thereby statistically increased compared to normal (P < 0.01). although the means remained in the reference range of 12-25 ml. Semen analysis revealed azoospermia in 70 of 71 (99%) patients and severe oligozoospermia <0.1 × 106/ml in one patient. Four semen parameters, i.e. ejaculate volume, pH, α-glucosidase and fructose values, were significantly reduced (P < 0.01). Only 18% of patients had a palpatory and sonographically diagnosed CBAVD, while in 31% the diagnosis of CBAVD was uncertain, in 12% patients, the vas deferens was present but hypoplastic, and in 39% the vas deferens was normally present bilaterally. Seminal vesicles were not detectable in 37% and only unilaterally present in 37% of patients. Apart from total testes volume, clinical findings were similar in patients with two confirmed pathogenic CFTR mutations (Group I) compared with patients who carried one pathogenic mutation and one CFTR variant of unknown significance (Group II). LIMITATIONS, REASONS FOR CAUTION: We could not formally confirm the in trans position of genetic variants in most patients as no family members were available for segregation studies. Nonetheless, considering that most mutations in our study have been previously described without other rare variants in cis, and in view of the compatible andrological phenotype, it is reasonable to assume that the biallelic genotypes are correct. WIDER IMPLICATIONS OF THE FINDINGS: Our study reveals that CFTR mutation analysis has a broader indication than just the absence of the vas deferens. We recommend to completely sequence the CFTR gene if there is a suspicion of obstructive azoospermia, and to extend this analysis to all patients with unexplained azoospermia in the presence of normal gonadotropin levels. STUDY FUNDING/COMPETING INTEREST(S): German Research Foundation Clinical Research Unit 'Male Germ Cells: from Genes to Function' (DFG CRU326, grants to F.T.). There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

When and how do patients with cardiac amyloidosis die?

BACKGROUND: Cardiac amyloidosis (CA) is an underappreciated cause of morbidity and mortality. Light-chain (AL) and transthyretin (ATTR) amyloidosis have different disease trajectories. No data are available on subtype-specific modes of death (MOD) in patients with CA. METHODS AND RESULTS: We retrospectively investigated 66 with AL and 48 with wild-type ATTR amyloidosis (ATTRwt) from 2000 to 2018. ATTRwt differed from AL by age (74.6 ± 5.4 years vs. 63 ± 10.8 years), posterior wall thickness (16.8 ± 3.3 mm vs. 14.3 ± 2.2 mm), left ventricular mass index (180.7 ± 63.2 g/m2 vs. 133.5 ± 42.2 g/m2), and the proportions of male gender (91.7% vs. 59.1%), atrial enlargement (92% vs. 68.2%) and atrial fibrillation (50% vs. 12.1%). In AL NYHA Functional Class and proteinuria (72.7% vs. 39.6%) were greater; mean arterial pressure (84.4 ± 13.5 mmHg vs. 90.0 ± 11.3 mmHg) was lower. Unadjusted 5-year mortality rate was 65% in AL-CA vs. 44% in the ATTRwt group. Individuals with AL-CA were 2.28 times ([95%CI 1.27-4.10]; p = 0.006) more likely to die than were individuals with ATTRwt-CA. Information on MOD was available in 56 (94.9%) of 59 deceased patients. MOD was cardiovascular in 40 (66.8%) and non-cardiovascular in 16 (27.1%) patients. Cardiovascular [28 (68.3%) vs. 13 (80%)] death events were distributed equally between AL and ATTRwt (p = 0.51). CONCLUSION: Our data indicate no differences in MOD between patients with AL and ATTRwt cardiac amyloidosis despite significant differences in clinical presentation and disease progression. Cardiovascular events account for more than two-thirds of fatal casualties in both groups.

The superficial cervical plexus block for postoperative pain therapy in carotid artery surgery. A prospective randomised controlled trial.

OBJECTIVES: Rapid and reliable neurological evaluation soon after carotid artery surgery is feasible with modern methods of general anesthesia, but postoperative pain therapy remains a challenge. Use of opioids can mask neurological deficits. We investigated whether superficial cervical plexus block reduced postoperative opioid consumption after carotid endarterectomy. DESIGN: Prospective, randomised, double-blinded, placebo controlled trial. METHODS: 46 patients undergoing unilateral carotid endarterectomy under general anesthesia were randomized to either superficial cervical block with ropivacaine (n=23) or placebo (n=23). A patient controlled analgesia device (PCA) delivering morphine was provided for all patients. Subjective pain levels (visual analog scale, VAS) were recorded. The primary outcome was total morphine consumption on discharge from the recovery room. Secondary outcomes included arterial pCO2 (as an indicator of central nervous effects of morphine) and patient satisfaction. RESULTS: No adverse effects of the superficial cervical plexus block were reported. Four patients in the placebo group were excluded because of other drug use post-operatively. Per protocol analysis compared 23 patients in ropivacaine group and 19 patients in the placebo group. The ropivacaine group had a significant reduction in morphine consumption (3.8+/-2.0 versus 12.9+/-4.0, p<0.001), lower maximal pain scores (2.6+/-2.0 versus 5.8+/-1.6, p<0.001), and paCO2 levels (39.0+/-2.6 versus 41.9+/-3.4, p=0.008) at discharge from the recovery room. Patient satisfaction (1=very good to 6=insufficient) was substantially higher in the ropivacaine group (1.7+/-0.7 versus 3.1+/-1.2, p<00.01). CONCLUSION: The significant and clinically relevant lower morphine consumption and pain score, as well as the substantially higher patient satisfaction demonstrate that superficial cervical plexus block provides effective pain relief for patients undergoing carotid endarterectomy.

C4d: a marker for hepatic transplant rejection.

BACKGROUND: Acute rejection is still a common complication of hepatic transplantation. The diagnosis, based on the histological examination of the graft, may be difficult to confirm in the setting of combined hepatitis C virus infection. The presence of C4d in the portal capillaries could facilitate differentiation between acute rejection and relapsed hepatitis C. The deposit of C4d provides evidence of activation of humoral immunity. To attempt to confirm this hypothesis, we searched for the presence of C4d in posttransplant hepatic biopsies. METHODS: Thirty-six biopsies from 34 patients were analyzed retrospectively. The samples had been requested for one of the following reasons: suspected rejection, relapsed hepatitis C infection, or systematic check-up 1 year after the transplant. RESULTS: C4d expression was common in biopsies classified as acute rejection (33%) and chronic rejection (100%). C4d was never detected in the event of recurrent hepatitis C infection without rejection. CONCLUSION: These results, which are comparable to recently published data, give credence to the theory that C4d could be used as a marker for rejection following hepatic transplantation.

Preoperative treatment of hepatocellular carcinoma with intra-arterial injection of 131I-labelled lipiodol.

BACKGROUND: Recurrence is common after surgery for hepatocellular carcinoma (HCC). METHODS: The efficacy of, and tolerance to, preoperative intra-arterial injection of (131)I-labelled lipiodol was examined in 34 patients with HCC, including 29 with cirrhosis. Twenty-five patients had a single hepatic tumour and the mean(s.d.) tumour size was 5.2(3.7) (range 2-15) cm. The patients received between one and three injections of (131)I-labelled lipiodol (60 mCi per injection) before surgery. Operations included 14 liver transplants, 13 minor hepatectomies, six major hepatectomies and one exploratory laparotomy. RESULTS: There was one complication after lipiodol injection due to acute ischaemia of the small bowel. Three of 34 patients died within 28 days, two after transplantation and one after resection. An objective tumour response (decrease in tumour size) was observed in 19 of 34 patients, and a complete histological response in eight of 34. There was an objective tumour response or major histological necrosis of lesions in 25 of 34 patients. The 5-year survival rate was 48.4(8.0) per cent, 69.0 per cent after transplantation and 36.0 per cent in patients who underwent resection. CONCLUSION: This preoperative method appeared to be well tolerated, and provided promising results in terms of macroscopic and microscopic tumour responses.

Interferon and ursodeoxycholic acid combined therapy in chronic viral C hepatitis: controlled randomized trial in 203 patients.

AIMS: This prospective randomized trial was carried out in order to determine whether the long-term administration of ursodeoxycholic acid after discontinuation of interferon had any beneficial effect on the clinical course of hepatitis C virus infection. METHODS: Enrolled in the study were 203 patients with chronic active hepatitis C. They were all given: interferon alpha-2a (3 MU subcutaneously thrice a week) and ursodeoxycholic acid (10 mg/kg/day) for 9 months. At month 9, biochemical responders only were randomized into ursodeoxycholic acid treatment or placebo for 12 additional months (double blind study). RESULTS: At the end of interferon therapy, 71 patients (37%) were virological responders and 107 (56%) patients were biochemical responders and were randomized: 54 into the ursodeoxycholic acid group and 53 into the placebo group. Sustained response was evaluated 12 months after withdrawal of interferon. Sustained biochemical and virological responses were, respectively, 30% and 22% in the ursodeoxycholic acid group and 46% and 32% in the placebo group, which did not significantly differ. Histological evolution of fibrosis and necrotic inflammatory activity were similar in the two groups. CONCLUSION: Continuation of ursodeoxycholic acid therapy after withdrawal of interferon in patients with end-of-treatment response did not result in any significant improvement either in the maintenance of response to interferon or in liver histology.

[Polyradiculoneuropathy in an adult with primitive hyperoxaluria]. / Polyradiculoneuropathie au cours d'une hyperoxalurie primitive de l'adulte.

From the age of 31 a patient began to suffer from recurrent calcium oxalate urolithiasis. Liver biopsy showed a decrease in catalytic activity of the hepatic peroxisomal enzyme alanine: glyoxilate aminotransferase (AGT), which was mistargeted from peroxisomes to mitochondria. The genetic analysis revealed a mutation of the AGT gene. At age 47 he developed end-stage renal failure and underwent hemodialysis. After 12 months of hemodialysis he presented a rapidly declining clinical condition, a decrease of the residual renal function, a livedo reticularis with painful of extremities, and shortly thereafter a general weakness, which predominated on lower limbs. Apart from renal failure, routine biological examination and CSF were normal. Nerve conduction studies and electromyography supported the diagnosis of polyradiculoneuropathy. Pathological studies revealed mixed demyelinating-axonal lesions and deposits of calcium oxalate crystals within the media and the intima of epineural arterioles. A combined liver-kidney transplant was rapidly performed. The patient's condition improved in a few months and motor signs completely disappeared.

[Patient-oriented anesthesia] . / Patientenorientierte Anästhesie.

Goals of this study were to quantify patients' preferences for anaesthesia care and to identify what they know about various tasks of an anaesthetist. On the day before surgery, 122 patients scheduled for elective procedures were interviewed using a structured questionnaire. A reliable pain relieve and unawareness as well as stable vital functions have priority in patients' preferences. Patients are also concerned with good postoperative pain relieve and the avoidance of nausea and vomiting. Not important are short preoperative soberness, rapid awakening and initial wide awakeness. Not informed about typical tasks of an anaesthetist are 28-51% of the patients. In order to obtain maximum patient satisfaction, a thorough education plus further continuous training are the essential items for a patient orientated health care management in anaesthesia, along with good medical and technical equipment. The wide spectrum of tasks of an anaesthetist must be better represented in order to strengthen the position of anaesthesia in the competition for rare resources. A postoperative visit, which is judged of 77% of the patients as important, offers a beginning.

[Detection of cerebral embolism using transcranial Doppler sonography: can artifacts be reliably recognized?]. / Zerebrale Emboliedetektion mittels transkranieller Dopplersonographie: Können Artefakte sicher erkannt werden?

A requirement for the use of TCD for the detection of emboli in the field of cardiac and vascular surgery is the reliable differentiation between true emboli and artifacts. In ten healthy volunteers we carried out a study to establish the method with which artefacts can most reliably be identified. Automatic detection of increasing signal intensity misinterpreted 14% of all artifacts as emboli; 1.7% of all artifacts sounded suspicious for embolism, and 0.6% met the classical criteria of an embolus. Using simultaneous recording of the flow signal in two sections of the middle cerebral artery, all artifacts were identified on the basis of their simultaneous manifestation. Reliable intra-operative differentiation of emboli from artifacts requires attentive, continuous acoustic and visual analysis of signals by an experienced investigator familiar with the surgical procedure. The introduction of a multiple-depth algorithm might significantly improve the automatic detection program.

[Epidemiology of hepatitis C virus infection in 1,304 HCV positive patients: variations according to the origin of transmission and year of diagnosis]. / Epidémiologie de l'infection virale C chez 1,304 sujets VHC positif. Variations en fonction du mode de contamination et de l'année du diagnostic.

UNLABELLED: The evolution of epidemiological data on hepatitis C virus infection is poorly documented and thus the impact of screening is difficult to evaluate. AIM: To study epidemiological variations based on the origin of transmission and the year of diagnosis of hepatitis C virus infection. METHODS: The files of all 1304 patients seen in the hepatology unit of the Rennes University Hospital were analyzed (retrospectively before and prospectively after October 1995) in relation to epidemiological features. RESULTS: Despite widespread screening which is the source of 60% of the diagnoses, the total number of new cases of hepatitis C infection per year has not increased. Compared to patients diagnosed in the first years following the discovery of the virus, patients recently identified were younger (42 +/- 14 years) and frequently drug addicts (40%). Aminotransaminases were normal in 20% of cases. The frequency of cirrhosis has declined (17%). There has been a decrease in the proportion of patients who undergo liver biopsy (50%) and treatment with interferon (one third of patients). CONCLUSIONS: The impact of screening on the number of newly treated patients seems to be lower than previously predicted.

Atherogenic properties of enzymatically degraded LDL: selective induction of MCP-1 and cytotoxic effects on human macrophages.

The mechanisms underlying the selective accumulation of macrophages in early atherosclerotic lesions are poorly understood but are likely to be related to specific properties of altered low density lipoprotein (LDL) deposited in the subendothelium. Enzymatic, nonoxidative degradation of LDL converts the lipoprotein to a potentially atherogenic moiety, enzymatically altered LDL (E-LDL), which activates complement and is rapidly taken up by human macrophages via a scavenger receptor-dependent pathway. Immunohistological evidence indicates that E-LDL is present in an extracellular location in the early lesion. We report that E-LDL causes massive release of monocyte chemotactic protein 1 (MCP-1) from macrophages and that expression of interleukin 8 or RANTES remains unchanged. Release of MCP-1 was preceded by a rapid expression of MCP-1 mRNA, which was detectable after 15 minutes, reached maximum levels after 1 hour, and remained detectable for 12 hours after exposure to concentrations as low as 10 microg/mL E-LDL. MCP-1 mRNA induction and protein release by E-LDL exceeded that evoked by oxidized LDL. Release of MCP-1 was dependent on de novo protein synthesis and on the activity of tyrosine kinases. At higher concentrations, E-LDL, but not oxidized LDL, exerted toxic effects on macrophages that in part appeared to be due to apoptosis. The results show that E-LDL possesses major properties of an atherogenic lipoprotein.

Evaluation of antiandrogen therapy in unresectable hepatocellular carcinoma: results of a European Organization for Research and Treatment of Cancer multicentric double-blind trial.

PURPOSE: The aim of the study was to evaluate the efficacy of antiandrogen therapy on overall survival and response in unresectable hepatocellular carcinoma (HCC). PATIENTS AND METHODS: A total of 244 patients with unresectable HCC were included in this multicentric double-blind trial. According to a two-by-two factorial design, patients were randomly assigned to receive one of the following treatments: pure antiandrogen plus placebo (A+P group, 60 patients); luteinizing hormone-releasing hormone (LHRH) agonist plus placebo (LHRH+P group, 62 patients); pure antiandrogen plus LHRH agonist (A+LHRH group, 62 patients); or placebo plus placebo (P+P group, 60 patients). Pure antiandrogen consisted of Anandron (Roussel-Uclaf Laboratory, Romainville, France) administered orally (300 mg daily for 1 month, then 150 mg daily). LHRH consisted of goseriline acetate (3.6 mg) or triptoreline (3.75 mg) administered monthly by subcutaneous injection. Treatment was given until death. Response was evaluated every 8 weeks according to World Health Organization (WHO) criteria. RESULTS: Six patients were considered ineligible. One patient had a complete response (A+P arm) and three had a partial response (two in the LHRH+P arm and one in the A+LHRH arm). An overall log-rank test did not demonstrate any significant difference in survival among the four arms. Taking the factorial design into account, comparison of survival showed no significant difference between Anandron-containing regimens and others, or between LHRH-containing regimens and others. No serious side effects occurred for any regimen. CONCLUSION: This controlled study shows clearly the lack of efficacy of androgen treatment in unresectable HCC.

A reappraisal of hepatic siderosis in patients with end-stage cirrhosis: practical implications for the diagnosis of hemochromatosis.

The aim of this study was to describe the histologic pattern of iron distribution in end-stage cirrhosis due to various causes and to test the reliability of the hepatic iron index (equal to hepatic iron concentration divided by age) in excluding or confirming associated hemochromatosis in such a condition. Large slices of the resected livers of 30 patients transplanted for alcoholic and/or viral end-stage cirrhosis were assessed histologically for iron distribution and biochemically for hepatic iron concentration in the least and the most iron-overloaded nodules of each case. HLA-A3 was used as the marker for the hemochromatosis gene in the population studied. Intranodular parenchymal siderosis was found in 23 cases (12 spotty, 11 diffuse) with diffuse intrabiliary iron deposits apparent in only two cases. Although in 14 patients the hepatic iron index was significantly high (> 1.9) so as to suggest hemochromatosis, these cases did not correspond to homozygous hemochromatosis with respect to the prevalence of HLA-A3 antigen. End-stage cirrhosis arising from different causes is frequently complicated by parenchymal siderosis that may mimic hemochromatosis, including a hepatic iron index greater than 1.9. The diagnosis of hemochromatosis in patients with end-stage cirrhosis, even those with a hepatic iron index greater than 1.9, should rely mainly on clinical and histologic data.

["De novo" cancer after organ transplantation]. / Les cancers "de Novo" après transplantation d'organe.

From March 1972 to 1st of January 1996, 804 kidney, liver and pancreas transplants were performed in 690 patients. 39 post transplant cancers occurred in 27 patients. 21 skin tumors (15 squamous cell carcinoma, 4 basocellular carcinomas, 1 squamous carcinoma, 1 melanoma), 4 squamous cancers (anus, esophagus, tongue, and parotid), 4 post-transplant lymphoproliferative disorders, 1 non-Hodgkin's lymphoma T, 4 gynecological tumors (breast, ovarian peritoneal carcinomatosis, 2 uterine cervix cancers), 4 miscellaneous tumors (larynx, right colon, brain, prostate, own kidney). 14 patients died (14/27: 52%). Post transplant de novo cancers are a major risk in transplant patients These cancers are mainly represented by skin tumors and lymphomas. Skin cancers are mainly spinocellular and occur in the areas which are exposed to the sun. Post transplant lymphoproliferative disorders are very close to Burkitt's lymphoma, they produced B lymphocyte proliferation due to the reduction of the control of T lymphocytes and induced by Epstein-Barr virus. They can disappear with the diminution of immunosuppression.

[200 first hepatic transplantation at the Rennes University Hospital]. / Les 200 premières transplantations hépatiques du C.H.U. de Rennes.

UNLABELLED: From 21st of april 1978 to 1st september 1994, 200 liver transplantations in 172 patients were performed in the Medical Center of University of Rennes. Three patients had a liver and kidney transplant. 26 patients received a second transplant (13%) and 2 patients a third transplant (1%). There were 110 males and 62 females with a mean age of 43.7 years (range 17 months-66 years). The indications of transplantations were the following: 22 fulminant hepatitis (12%), 104 cirrhosis (60.5%), including 41 alcoholic cirrhosis (24%), 21 post-hepatitis B cirrhosis (12.2%), 24 post-hepatitis C cirrhosis (14%), 6 autoimmune cirrhosis, 7 primary biliary cirrhosis (4%), 21 non A non B cirrhosis (12.9%), 3 undetermined cirrhosis. Thirty one patients had a liver transplantation for cancer. The other indications were 5 sclerosing cholangitis and 2 atresia of the biliary tract. 45% of the patients had an uneventful postoperative course. In hospital mortality rate is related to the indication and Child Pugh classification in cirrhotic patients. The vascular surgical complications were 8.5%, biliary complications 6.1%, intra-abdominal infection 9.2%, intra-abdominal bleeding 5.5%. The rate of reoperation was 18.5%. 23 re-transplantations were performed in emergency and 6 electively (one from outside). The overall survival of patients from 1978 to 1994, including the patients before cyclosporine era, the use of extracorporeal circulation, the preservation with Wisconsin solutions and with main indications for cancer was 69% at 1 year and 59% at 5 years. After 1988, the overall patient survival was 75% at 1 year and 70% at 5 years. The graft and patient survival is mainly related to the indications. In fulminant and subfulminant hepatitis, the quality of the graft was preferred as often as possible. The actuarial graft survival at 1 year, 3 years and 5 years was respectively 75%, 70.45% and 70.45%. The actuarial patient survival was 77.3%, 72.5% and 72.5%. In liver transplantation for cancer, the actuarial patient survival at 1 year, 3 years and 5 years is respectively 55%, 32% and 23.5%. 5 patients are alive and well at 5 years, including a patient who underwent a Cluster operation for Klatskin tumor. In post-hepatitis cirrhosis, the patient actuarial survival at 1 year, 3 years and 5 years was 79%, 76.5% and 76.5% and in alcoholic cirrhosis 75%, 72% and 72%. The actuarial survival is closely related to Child Pugh Classification (at one year Child A 87%, Child B 72.4%, Child C 58%). CONCLUSION: in this series of the first 200 liver transplants at the University of Rennes Medical Center, graft and patient survival depends on the evolution of the surgical technic but it is also closely related to the indication. In fulminant hepatitis, the quality of the graft (without incompatible graft, if possible) should permit to avoid retransplantation and to obtain results closely to the elective transplantation. Liver transplantation for cancer should be restricted. In cirrhosis, results are depending upon Child Pugh classification. The conclusions of Paris consensus conference should be followed. The limited number of donor livers call for the "priorization" (T.E. Starzl) favoring those patients who will benefit most, i.e., patients with the most serious conditions and the poorest short term vital prognosis.

Different forms of streptolysin O produced by Streptococcus pyogenes and by Escherichia coli expressing recombinant toxin: cleavage by streptococcal cysteine protease.

To resolve apparent discrepancies in the literature, N-terminal sequences of the active high- and low-molecular-weight (high- and low-M(r)) forms of native streptolysin O (nSLO) purified from Streptococcus pyogenes culture supernatants and of the similar-size high- and low-M(r) forms of recombinant SLO (rSLO) found in the periplasm of Escherichia coli expressing a cloned slo gene were determined. The high-M(r) forms of nSLO and rSLO are identical, reflecting removal of a 31-residue signal peptide, but the similar-size low-M(r) forms are very different. Removal of C-terminal sequences by proteases in the E. coli periplasm produces an inactive low-M(r) form of rSLO. In contrast, an active low-M(r) form of nSLO is produced by proteolytic cleavage between the N-terminal residues Lys-77 and Leu-78, which was shown to correspond to an extremely sensitive cleavage site for the pyrogenic exotoxin B-derived streptococcal cysteine protease.

Altered pore-forming properties of proteolytically nicked staphylococcal alpha-toxin.

Staphylococcal alpha-toxin is a single-chain polypeptide with a molecular weight of 34,000 that hexamerizes in lipid bilayers to form pores of 1-1.5 nm effective diameter in membranes. We demonstrate that limited proteolysis of purified alpha-toxin with proteinase K generates a hemolytically active product that yields one major protein band of 17-18 kDa in SDS-polyacrylamide gel electrophoresis. The 17-18-kDa protein band harbors two major fragments of similar size representing the N- and C-terminal halves, which remain associated with each other in non-denaturing buffers but dissociate in 6 M urea. Dissociation in urea leads to loss of hemolytic activity. In contrast, unnicked alpha-toxin is not inactivated by urea. Nicked, hemolytically active alpha-toxin forms hexamers on erythrocyte membranes and on lymphocytes and monocytes. However, the nicked toxin can only lyse erythrocytes and fails to permeabilize nucleated cells. Osmotic protection experiments indicate that the size of pores generated by the nicked toxin is considerably smaller (0.6-0.9 nm effective diameter) than that generated by native toxin. The collective results do not support a previous proposal that different functions of alpha-toxin are contained in separate domains of the molecule.

Chemoembolization of hepatocellular carcinomas. A study of the biodistribution and pharmacokinetics of doxorubicin.

BACKGROUND: This study evaluated the effects of an association of ethiodized oil (Lipiodol Ultra Fluide, Laboratoires Guerbet, Aulnay-sous-Bois, France), with or without gelatin sponge, with doxorubicin (Adriamycin, Adria Laboratories, Columbus, OH) on the biodistribution and kinetics of doxorubicin during intraarterial injection. METHODS: Eighteen patients with hepatocellular carcinoma on cirrhotic liver received a therapeutic injection into the hepatic artery of 50 mg of doxorubicin alone (Group 1; n = 4), or emulsified in 10 ml of ethiodized oil and 2.5 ml of ioxaglate (Hexabrix, Laboratoires Guerbet) with (Group 2; n = 7) or without (Group 3; n = 7) gelatin sponge embolization. Before treatment, the absence of intrahepatic shunts was verified by an injection of technetium-labeled albumin macroaggregates. The biodistribution of doxorubicin was studied on two fronts: (1) pharmacokinetic--by measurement of the doxorubicin blood level during the 48 hours after injection; and (2) scintigraphic (2 mg of doxorubicin were labeled with 2 mCi of iodine 131)--by examination of the scintigrams and calculation of the following parameters: tumours liver/nontumorous liver binding ratio (T/NT ratio), liver/liver+lungs+abdomen binding ratio, and doxorubicin half-life in tumorous tissue. RESULTS: Pharmacokinetics results showed the following: the peak plasma concentration was significantly higher in Group 1 as compared with Groups 2 or 3 (Group 1: 2.1 +/- 0.9 mg/ml; Group 2: 0.9 +/- 0.3 mg/ml; Group 3: 0.5 +/- 0.2 mg/ml); the area under curve calculated from time zero to 1 hour was lower in Groups 2 and 3 compared with Group 1. Examination of the scintigrams showed the following: diffuse activity throughout the organism (Group 1), diffuse activity with strong hepatic and tumorous binding (Group 2), and mostly hepatic and tumoral binding (Group 3). The liver/liver+lungs+abdomen binding ratio was 28% +/- 1% in Group 1, 36% +/- 5% in Group 2, and 63% +/- 7% in Group 3. The T/NT ratios were 1.0 +/- 0 (Group 1), 1.5 +/- 0.1 (Group 2), and 4.7 +/- 0.5 (Group 3). The doxorubicin half-lives in tumourous tissue were 0.7 +/- 0.1 days (Group 1), 1.8 +/- 0.2 days (Group 2), and 2.6 days (n = 1; Group 3). CONCLUSIONS: This study shows (1) that the association of ethiodized oil with doxorubicin lowers the peak concentration of doxorubicin and increases the intratumoral concentration and half-life of doxorubicin, and (2) that these kinetic ameliorations are even more pronounced after embolization. Therefore, from a kinetic standpoint, the doxorubicin-ethiodized oil-gelatin sponge association is the best.

Magnetic resonance imaging and assessment of liver iron content in genetic hemochromatosis.

Computed tomography (CT) scanning is not highly sensitive in the assessment of liver iron content and magnetic resonance imaging (MRI) appears to be more efficient. The aim of this study was to determine the effectiveness of MRI in the evaluation of liver iron content using a standard spin-echo technique. The study included 23 patients with genetic hemochromatosis and 24 non-iron-overloaded patients as controls. A comparison was made of: (a) MRI signal intensity of liver, spleen, paravertebral muscles and subcutaneous adipose tissue using two different spin-echo sequences (SE 500/28; SE 2000/28,56); (b) liver attenuation determined by a single energy CT scan; and (c) a biochemical determination of hepatic iron. There was a significant decrease in liver signal intensity in the genetic hemochromatosis group (256 +/- 201, mean +/- S.D.) compared with the control group (801 +/- 413, p less than 0.001), but there was no correlation with liver iron concentration. However, such a correlation was found and was even more highly significant than in CT when the ratio between the liver and another organ was taken into account. For a lower limit of liver/spleen ratio calculated at 0.46 (mean 2 S.D. in the control group), the specificity (0.96) of MRI was satisfactory, but the sensitivity (0.78) remained insufficient (MRI being unable to detect an iron overload of up to 125 mumol/g). Hopefully, these results might be improved in the near future by using more sensitive sequences such as gradient echo sequences.