Structure and replication of the genome of the hepatitis delta virus

The hepatitis delta virus can be found in the serum and liver of some hepatitis B virus patients. We now report that the RNA genome of serum-derived delta virus is single-stranded and circular. Livers of infected chimpanzees or woodchucks contained as many as 300,000 copies of genomic strand RNA per average cell, and at least some of this RNA had a circular conformation. Also present in the livers were RNA species complementary to the virion RNA. The genomic RNA was 5-22 times more abundant than this antigenomic strand. Some of the antigenomic RNA was complexed with genomic RNA, as evidenced by the fact that at least 34% of the antigenomic RNA was resistant to digestion with either RNase A in 0.3 M NaCl or S1 nuclease. Some of the antigenomic RNA was in a circular conformation. These and other findings showed that the structure and replication of hepatitis delta virus are in many ways similar to those of the previously described plant viroids, virusoids, and satellite RNAs.

Prevalence of respiratory and atopic disorders among children in the East and West of Germany five years after unification

Living conditions in eastern Germany have changed rapidly since unification in 1990 and little is known about how these changes affect the prevalence of atopic diseases. This study describes methods and prevalences of a large epidemiological project investigating determinants of childhood asthma and allergies in eastern (Dresden and Leipzig) and western (Munich) Germany in 1995/1996. Community based random samples of 9-11 yr old children in Dresden (n=3,017) and Munich (n=2,612), and of 5-7 yr old children in Dresden (n=3,300), Leipzig (n=3,167) and Munich (n=2,165) were studied by parental questionnaires, bronchial challenges with hypertonic saline, skin examination, skin-prick tests, and measurements of specific and total serum immunoglobulin (Ig)E using Phase II modules of the International Study of Asthma and Allergies in Childhood (ISAAC). In 9-11 yr old children, the prevalence of physician diagnosed asthma (7.9% versus 10.3%; p<0.01) and bronchial hyperresponsiveness (15.7% versus 19.9%; p<0.05) was lower in Dresden than in Munich. No difference between Munich and Dresden was observed in the prevalence of diagnosed hay fever, skin test reactivity to > or = 1 allergen, and increased levels (>0.35 kU x L(-1)) of specific IgE against inhalant and food allergens. Symptoms and visible signs of atopic eczema tended to be more prevalent in Dresden. Similar East-West differences between the three study areas were seen in the younger age group. These findings are in line with recently observed increases in the prevalence of hay fever and atopic sensitization, but not of asthma and bronchial hyperresponsiveness, among 9-11 yr old children in Leipzig.

Neuropathological findings after bone marrow transplantation: an autopsy study of 180 cases

We prospectively evaluated the neuropathological complications of 180 patients who underwent autopsy studies following bone marrow transplantation (BMT) (177 allogeneic, three autologous). The most frequent underlying disorders included severe aplastic anemia (n = 55), chronic myelogenous leukemia (n = 53), acute myelogenous leukemia (n = 24) and Fanconi anemia (n = 16). There were 114 males and 66 females. Neuropathological findings were detected in 90.55% of the patients. The most frequent findings were subarachnoid hemorrhages (SAH) (n = 57), intraparenchymal hemorrhages (IHP) (n = 49), fungal infections (n = 16), Wernicke's encephalopathy (n = 10), microglial nodular encephalopathy (n = 10) and neurotoxoplasmosis (n = 8). In only 17 patients was the brain within normal limits. Survival time after BMT averaged 5.4 months and the majority of patients died in the first 3 months post BMT (n = 105). Central nervous system (CNS) pathology was the main cause of death in 17% of the patients (n = 31), with a predominance of IHP in this particular group. Furthermore, the survival time of these patients who died of CNS causes (96.3 days) was almost half of the survival time of those who died of extra-cerebral causes (177.8 days) (P = 0.0162). IHP (70. 96 vs27.22%) (P < 0.001), fungal infections (25.8 vs 8.88%) (P < 0. 001) and toxoplasmosis (9.67 vs 4.44%) (P < 0.001) were significantly more frequent in the group of patients who died due to CNS causes than in the control group. The findings of this work provide a possible guide to the possible causes of neurological syndromes following BMT. Bone Marrow Transplantation (2000) 25, 301-307.

Antibody to hepatitis-B core antigen in patients with primary hepatic carcinoma

Antibody to hepatitis-B core antigen (anti-HBc) was assayed in the serum of patients with primary hepatic carcinoma (P.H.C.) and controls from Hong Kong, West Africa, and the United States. In each region the prevalence of anti-HBc was higher in P.H.C. patients than in controls, ranging from 70 to 95% in the patients and from 20 to 68% in the controls from Asia and Africa; 24% of P.H.C. patients and 4% of controls from the U.S. had anti-HBc. These data support the hypothesis that chronic infection with hepatitis-B virus is aetiologically related to P.H.C., especially in Asia and Africa, although other factors must also be involved.

Widespread West Nile virus activity, eastern United States, 2000

In 1999, the U.S. West Nile (WN) virus epidemic was preceded by widespread reports of avian deaths. In 2000, ArboNET, a cooperative WN virus surveillance system, was implemented to monitor the sentinel epizootic that precedes human infection. This report summarizes 2000 surveillance data, documents widespread virus activity in 2000, and demonstrates the utility of monitoring virus activity in animals to identify human risk for infection.

Disseminated toxoplasmosis after bone marrow transplantation: report of 9 cases

Toxoplasma infection following bone marrow transplantation (BMT) is infrequently reported. We report 9 cases of disseminated Toxoplasma gondii infection in BMT recipients documented during an 11-year period at our institution. The incidence of T. gondii infection in our institution (1.14 per 100 allogeneic BMT) is higher than previously reported. The most frequently affected sites were the brain, lungs, and heart. Findings common to most patients who developed toxoplasmosis were positive pre-transplant serology, allogeneic transplant and graft-versus-host disease and its treatment, as well as BMT from matched unrelated donors. All 9 patients died and 8 were diagnosed only after autopsy. Heightened awareness of the occurrence of toxoplasmosis in marrow recipients, especially in highly endemic areas, and early diagnosis and therapy are needed for a better outcome.

Protective effect of breastfeeding on invasive Haemophilus influenzae infection: a case-control study in Swedish preschool children

BACKGROUND

In Orebro County a 2.5-fold increase in the incidence of Haemophilus influenzae (HI) meningitis was found between 1970 and 1980, an observation that initiated the present study.

MATERIALS AND METHODS

In order to search for associations between morbidity in invasive HI infection and possible risk factors, a case-control study was conducted over a 6-year period from 1987 to 1992, before general Hib vaccination was introduced in Sweden. Fifty-four cases with invasive HI infection 139 matched controls were studied for possible risk factors such as day-care outside the home, short duration of breastfeeding, passive smoking, low socioeconomic level of the household, many siblings in the family, allergy, frequent, infections, repeated antibiotic treatments and immunoglobulin deficiency.

RESULTS

Multivariate analysis showed a significant association between invasive HI infection and two independent factors, i.e. short duration (< 13 weeks) of exclusive breastfeeding, odds ratio (OR) 3.79 (95% confidence interval [CI] 1.6-8.8) and history of frequent infections, OR 4.49 (95% CI : 1.0-21.0). For the age at onset 12 months or older, the associations were stronger, OR 7.79 (95% CI : 2.4-26.6) and 5.86 (95% CI : 1.1-30.6), respectively. When breastfeeding duration in weeks was analysed as a continuous variable the OR was 0.95 (95% CI : 0.92-0.99), indicating a decreased risk with each additional week. Increased OR were observed for other risk factors as well but not of the magnitude found for short duration of breastfeeding.

DISCUSSION

The association of decreased risk for invasive HI infection and long duration of breastfeeding was persisting beyond the period of breastfeeding itself. This finding supports the hypothesis of a long-lasting protective effect of breastfeeding on the risk for invasive HI infection.

CONCLUSION

A decreased risk for invasive HI infection with long duration of breastfeeding was found. Our results do have implications for strategies in breastfeeding promotion, especially in countries where Hib vaccination is too costly and not yet implemented.

Evolutionary dynamics of residual disease in human glioblastoma

BACKGROUND

Glioblastoma is the most common and aggressive adult brain malignancy against which conventional surgery and chemoradiation provide limited benefit. Even when a good treatment response is obtained, recurrence inevitably occurs either locally (∼80%) or distally (∼20%), driven by cancer clones that are often genomically distinct from those in the primary tumour. Glioblastoma cells display a characteristic infiltrative phenotype, invading the surrounding tissue and often spreading across the whole brain. Cancer cells responsible for relapse can reside in two compartments of residual disease that are left behind after treatment: the infiltrated normal brain parenchyma and the sub-ventricular zone. However, these two sources of residual disease in glioblastoma are understudied because of the difficulty in sampling these regions during surgery.

PATIENT AND METHODS

Here, we present the results of whole-exome sequencing of 69 multi-region samples collected using fluorescence-guided resection from 11 patients, including the infiltrating tumour margin and the sub-ventricular zone for each patient, as well as matched blood. We used a phylogenomic approach to dissect the spatio-temporal evolution of each tumour and unveil the relation between residual disease and the main tumour mass. We also analysed two patients with paired primary-recurrence samples with matched residual disease.

RESULTS

Our results suggest that infiltrative subclones can arise early during tumour growth in a subset of patients. After treatment, the infiltrative subclones may seed the growth of a recurrent tumour, thus representing the 'missing link' between the primary tumour and recurrent disease.

CONCLUSIONS

These results are consistent with recognised clinical phenotypic behaviour and suggest that more specific therapeutic targeting of cells in the infiltrated brain parenchyma may improve patient's outcome.

Central nervous system infections following bone marrow transplantation: an autopsy report of 27 cases

The authors retrospectively assess the autopsy findings of central nervous system (CNS) infections in marrow transplant recipients. From July 1987 to June 1998, 845 patients at our institution were submitted to bone marrow transplantation (BMT). The CNS of 180 patients was studied through autopsy and these patients had their medical records reviewed. Twenty-seven (15%) patients presented brain parenchyma infection. Fungi were isolated in approximately 60% of the cases. Mean survival time was 153 days (0-1,264 days) and the majority of the patients died during the first 3 months after BMT (18 cases; 67%). Aspergillus sp. were the most prevalent fungi (approximately 30%), followed by Candida sp. infection (approximately 18%). There was one case of Fusarium sp. infection and two cases of unidentified fungus. All patients with fungal infections had documented involvement at widespread sites. Toxoplasma gondii encephalitis was demonstrated in 8 patents (approximately 30%). Bacterial abscesses were responsible for approximately 11% of the findings. Eleven (41%) of the 27 patients died secondary to cerebral causes. These results show that infectious compromise of the CNS following BMT is a highly fatal event, caused mainly by fungi and T. gondii. Furthermore, they provide a likely guide to the possible causes of brain abscesses following BMT.

Cholecystectomy and carcinoma of the colon. An experimental study

The influence of cholecystectomy on the development of carcinoma of the colon is investigated. The experimental results show a significantly increased rate of carcinoma of the colon induced by subcutaneous injection of 1,2-Dimethylhydrazin (DMH) in the mouse after cholecystectomy. After 10 weekly injections of 15 mg/kg DMH, 70% of the animals with cholecystectomy developed carcinoma. Only 16% of the mice with similar treatment but without cholecystectomy had carcinoma. The cocarcinogenic effect of cholecystectomy is assumed to be due to the increased production of secondary bile salts by the colonic bacteria and the lacking of the resorptive function of the gallbladder for some carcinogenic substances passing through the liver. The background of this experimental studies are the clinical findings that 10% of patients with carcinoma of the large bowel had previous cholecystectomy.

Involvement of oxygen radicals in cytarabine-induced apoptosis in human polymorphonuclear cells

We investigated apoptosis in polymorphonuclear neutrophils (PMNs) induced by cytarabine (Ara-C). This drug increased apoptosis by 100% with respect to the controls after 3 hr of incubation. This increase was inhibited by N-acetyl-L-cysteine (NAC) or diphenyleneiodonium chloride (DPI). Ara-C alone caused an early increase (after a 30-min incubation) in intracellular oxidant generation (inhibitable by rotenone, fumonisin b1, and DPI) and in protein tyrosine phosphorylations (inhibitable by NAC). The drug also affected the observed reduction of dimethylthiazol diphenyltetrazolium bromide (MTT). No extracellular release of reactive oxygen species (ROS) was elicited by the addition of Ara-C, while the drug increased the release of ROS by N-formyl-leucyl-phenylalanine-(f-MLP) but not phorbol 12-myristate 13-acetate-stimulated PMNs. This phenomenon was abolished by the addition of genistein, whereas such an effect was not observed following the addition of 1-(5-isoquinolynilsulfonyl)-2-methylpiperazine (H7). Ara-C induced ROS release from PMNs in the presence of subthreshold concentrations of f-MLP (priming effect). These results indicate that intracellular ROS production from mitochondria promotes Ara-C-induced apoptosis. Ara-C primes plasma membranes by a mechanism involving protein tyrosine phosphorylations and may also contribute to ROS generation from the granules.

Workplace risk factors for cancer in the German rubber industry: Part 2. Mortality from non-respiratory cancers

OBJECTIVES

To determine the mortality from non-respiratory cancers by work area among active and retired male workers of the German rubber industry.

METHODS

A cohort of 11,633 male German workers was followed up for mortality from 1 January 1981 to 31 December 1991. Cohort members were active (n = 7536) or retired (n = 4127) on 1 January 1981 and had been employed for at least one year in one of five study plants producing tyres or technical rubber goods. Work histories were reconstructed from routinely documented "cost centre codes" and classified into six categories: I preparation of materials; II production of technical rubber goods; III production of tyres; IV storage and dispatch; V general service; VI others. Standardised mortality ratios (SMRs) and 95% confidence intervals (95% CIs), controlling for age and calendar year and stratified by work area (employment in respective work area for at least one year) and time related variables (year of hire, lagged years of employment in work area) were calculated from national mortality rates as the reference.

RESULTS

Significant increases in mortality were found for pharyngeal cancer in work area IV (three deaths, SMR 486, 95% CI 101 to 1419), oesophageal cancer in work area III (11 deaths, SMR 227, 95% CI 114 to 407), and leukaemia in work areas I (11 deaths, SMR 216; 95% CI 108 to 387) and II (14 deaths, SMR 187; 95% CI 102 to 213). Furthermore, increased SMRs were found for stomach cancer in work area I (22 deaths, SMR 134; 95% CI 84 to 203), colon cancer in work area II (27 deaths, SMR 131, 95% CI 86 to 191), prostatic cancer in work area V (27 deaths, SMR 152, 95% CI 99 to 221), and bladder cancer in work areas IV (six deaths, SMR 253; 95% CI 93 to 551) and V (12 deaths, SMR 159, 95% CI 82 to 279). Mortality from cancer of the liver or gall bladder, pancreas and kidney, and from lymphomas was not substantially increased in any of the work areas.

CONCLUSIONS

Mortality from cancer of several sites was associated with specific work areas. Some of these associations have been reported previously. Future analyses of our study will have to determine the role of specific exposures in the aetiology of these cancers.

Comparison of protocols for DNA extraction from long-term preserved formalin fixed tissues

The current study compared the applicability of protocols to extract DNA from formalin fixed heart tissues that have been preserved for more than 50 years. Ten methods were tested: a cetyltrimethylammonium bromide (CTAB) standard protocol, seven variants of this standard protocol, and two commercial kits. In the case of younger specimens (fixed in 1951, 1934, or 1914), extracts with DNA concentrations ≥ 10.0 ng/μl were obtained with the standard CTAB protocol, two variants of the standard protocol including prolonged tissue digestion (72 h instead of 1-2h), and a commercial kit particularly recommended for DNA extraction from formalin fixed paraffin embedded tissues (FFPE Kit). With the FFPE Kit, DNA could also be extracted from older tissues (fixed in 1893, 1850/1851, or before 1820). In general, the purity of the DNA extracts, assessed from the ratio of the absorbance at 260 and 280 nm, was not very high. In spite of their rather low purity, the DNA extracts could, however, be used to amplify a 122-bp sequence and, in most cases, also a 171-bp sequence of the gene coding for human albumin by the polymerase chain reaction (PCR).

Intracranial hemorrhage following bone marrow transplantation: an autopsy study of 58 patients

Autopsy files of 180 patients were reviewed, who died after BMT between July 1987 and June 1998 and 58 (32.2%) cases, who had experienced intracranial hemorrhage (ICH) were selected. Age, sex, underlying disease, preparatory regimens, immunoprophylaxis, chronic and acute GVHD, survival of the patients and localization and size of hemorrhages were evaluated. There were 33 males and 25 females, with a mean age of 23.4 years. The main underlying disorders for which BMT was performed included SAA (n = 21), CML (n = 13) and AML (n = 10). Forty patients were found to have intraparenchymal hemorrhage, 35 had subarachnoid hemorrhage and eight patients had subdural hemorrhage. In 16 cases the CNS hemorrhage was so extensive that it was considered to be the main cause of death. There was no significant statistical difference concerning sex (P = 0.217), age (P = 0.296), underlying disease (P= 0.352), preparatory regimens (P = 0.07), immunoprophylaxis (P = 0.914), chronic and acute graft-versus-host disease (P = 0.107 and P = 0.631, respectively) and survival (P = 0.701) when comparing patients with or without ICH. However, the number of cases in which the CNS was defined as the main cause of death was higher among patients with ICH than in patients without ICH (n = 16 vs 15) (P = 0.011). We conclude that ICH is common and has a significant mortality rate following BMT.