Cytogenetic findings in adult de novo acute myeloid leukaemia. A population-based study of 303/337 patients

During a 10-year period (1992-2001) in the region of Southern Denmark, 337 patients aged 15 years or older (range 16-93 years, median 67 years) were diagnosed with acute myeloid leukaemia (AML). Cytogenetic analysis was carried out in 90%, of whom 53% had clonal chromosome aberrations. Some 24% and 31% had only numerical or structural abnormalities respectively. The remaining patients showed both types of abnormalities. Ploidy levels in decreasing order were: pseudodiploidy, 41%; hyperdiploidy, 32%; and hypodiploidy, 27%. Pseudodiploidy characterizes type M3 (70%) and hypodiploidy M6 (56%). Recurrent cytogenetic abnormalities--t(8;21), t(15;17) and inv(16)--were found in 3.3%, 3.3% and 2.0% of all patients respectively. Prognostically intermediate and adverse aberrations were found in 39% and 44%, respectively, of those with an abnormal karyotype. Rare recurrent aberrations were found in two patients in this material. A previously described non-recurrent abnormality was found to be recurrent in one patient [der(20)t(11;20)(q13.2;p13)]. New, previously undescribed abnormalities were found in 41 patients. Statistically significant correlations were found between t(15;17) and young age (P < 0.001), inv(16) and young age (P < 0.006), -17 and M6 (P = 0.007), and M6 and complex karyotype with five or more unrelated aberrations (P = 0.004). We conclude that this truly population-based cytogenetic study of adult AML showed distributions of chromosome abnormalities that differ from those described so far.     

Round-robin analysis of the RILEM TC 162-TDF beam-bending test: Part 3—Fibre distribution

A round robin test programme was executed amongst several laboratories on the beam test recommended by the RILEM TC 162-TDF [1]. In the proposed test method, the mid-span deflection is to be measured on both sides of the beam (referred to as δ₁ and δ₂). A systematic fibre counting exercise was carried out on several beam specimens to investigate whether there is a correlation between differences between δ₁ and δ₂ and the fibre distribution. The findings of the investigation suggest that differences between δ₁ and δ₂ are not strongly linked with the fibre distribution regardless of concrete strength. It is likely that this phenomenon arises because the supports and loading points have enough degrees of freedom to accommodate any unevenness on the specimen surface. This reflects well on the robustness of the proposed test method as it means that the proposed boundary conditions are able to adapt and tolerate (to a certain degree) surface non-uniformity. However, it is also suggested that significant differences between δ₁ and δ₂ may be brought about by experimental errors. The fibre count also reveals that toughness increases with the number of fibres across the critical section.     

Perfluorocarbons: recent developments and implications for neurosurgery

Over the last 30 years, perfluorocarbons (PFCs) have been extensively investigated as oxygen carriers. Early studies indicated that these compounds could be used as blood substitutes or protective agents against ischemia. Adverse characteristics such as instability, short intravascular half-life, and uncertainties concerning possible toxicity precluded wide clinical application. However, advances in PFC technology have led to the development of improved second-generation oxygen carriers that incorporate well-tolerated emulsifiers (egg-yolk phospholipids). The authors review recent developments in this field and consider the potential role of PFCs in future neurosurgical practice. Diagnostic applications could include their use to assess cerebral blood flow, local oxygen tension, and brain metabolism or to achieve enhanced imaging and precise staging of inflammatory, neoplastic, or vascular disease processes by means of computerized tomography, ultrasonography, and magnetic resonance studies. Therapeutic applications could include cerebral protection, an adjunctive role in radiotherapy of malignant brain tumors, protection against air embolism, the preservation of organs for transplantation, and ventilatory support in head-injured patients with compromised lung function. In addition, PFCs have been used successfully as a tool in ophthalmic microsurgery and potentially they could fulfill a similar role in microneurosurgery.     

Sepsis in the very low-birth-weight newborn infant

Sepsis is a common pathology during the neonatal period. Low-birth weight is the most important isolated risk factor. With the purpose of determining the prevalence of nosocomial infection in newborns of very low birth weight (VLBW), finding the microbial flora and the mortality of these patients, the authors retrospectively analysed the clinical processes of the hospitalized VLBW in the Neonatal Intensive Care Unit (NICU) in S. Jo?o Hospital in 1993 and 1994. Of the 1091 newborns admitted to the hospital in these two years, 112 were VLBW (10%). Of these, 48 had sepsis-31 (28%) confirmed sepsis and 17 (15%) probable sepsis. The agents most commonly found were Staphylococcus epidermidis (44%) and Klebsiella pneumoniae (21%). Thirteen patients (27%) died, with infection as the cause of death in nine (19%). Our results confirm the importance of nosocomial neonatal infection, which should involve the strict observance of the asepsis norms and a proper policy of antibiotics.     

Coexistence of migraine and idiopathic intracranial hypertension without papilledema

Eighty-five patients with refractory transformed migraine type of chronic daily headache (CDH) had spinal tap as a part of diagnostic work-up. Twelve had increased intracranial pressure without papilledema, transient visual obscurations, or visual field defects. The headache profile of these 12 patients was not different from that of transformed migraine type of CDH. Acute headache exacerbations responded to specific antimigraine agents such as ergotamine, dihydroergotamine (DHE), and sumatriptan, whereas prophylactic antimigraine medications were only partially helpful. Addition of agents such as acetazolamide and furosemide, after the diagnosis of increased intracranial pressure, resulted in better control of symptoms. These observations suggest a link between migraine and idiopathic intracranial hypertension that needs further research. In refractory CDH with migrainous features, a spinal tap to exclude coexistent idiopathic intracranial hypertension without papilledema may be indicated.     

Australian-Indonesian collaboration in veterinary arbovirology--a review

Australian-Indonesian collaboration in veterinary development programs has led to significant advances in the study of arboviruses. This paper reviews the resulting knowledge of arboviral infections of livestock in Indonesia. The first recognized arboviral disease of animals in Indonesia was bovine ephemeral fever. Serology indicates that the virus is widespread, as are related rhabdoviruses. Local sheep appear resistant to bluetongue disease, but imported sheep have suffered mortalities. Bluetongue viral serotypes 1, 7, 9, 12, 21 and 23 have been isolated from sentinel cattle; 1, 21 and 23 at widely separate locations. Bluetongue serotype 21 has been isolated from Culicoides spp. Serological reactors to Akabane virus are widespread, as are reactors to the flavivirus group. Japanese encephalitis, isolated from sentinel pigs, is the flavivirus of most veterinary importance but the limit of its easterly distribution is unknown. Many of the arboviruses present in Indonesia are also present in Australia and elsewhere in Asia. Their patterns of mobility among countries in the region are largely undescribed, but there are opportunities for further regional collaboration.     

Bladder carcinoma in Ibadan Nigeria: a changing trend?

A review of cases of bladder carcinoma in Ibadan, Nigeria between 1979-1989 suggest a changing trend with a rise in the frequency of transitional cell carcinoma (49.9%) relative to squamous cell carcinoma (SCC). Earlier reports from Ibadan indicated a preponderance of SCC. However, similar to other reports, SCC is more frequent amongst those aged 50 years and below (45.5%) compared to TCC (18%). This frequency has often been related to schistosomal infestation. Though the possibility of age-related factors are considered, the significance of changing environmental and socio-economic factors are highlighted. Whilst better public enlightenment and health education, may help in lowering the intensity of schistosomal infestation, increasing urbanization and industrialization may be increasing environmental factors that predispose to transitional (urothelial) cell carcinoma of the bladder.     

The use of continuous i.v. sedation is associated with prolongation of mechanical ventilation

STUDY OBJECTIVE: To determine whether the use of continuous i.v. sedation is associated with prolongation of the duration of mechanical ventilation. DESIGN: Prospective observational cohort study. SETTING: The medical ICU of Barnes-Jewish Hospital, a university-affiliated urban teaching hospital. PATIENTS: Two hundred forty-two consecutive ICU patients requiring mechanical ventilation. INTERVENTIONS: Patient surveillance and data collection. MEASUREMENTS AND RESULTS: The primary outcome measure was the duration of mechanical ventilation. Secondary outcome measures included ICU and hospital lengths of stay, hospital mortality, and acquired organ system derangements. A total of 93 (38.4%) mechanically ventilated patients received continuous i.v. sedation while 149 (61.6%) patients received either bolus administration of i.v. sedation (n=64) or no i.v. sedation (n=85) following intubation. The duration of mechanical ventilation was significantly longer for patients receiving continuous i.v. sedation compared with patients not receiving continuous i.v. sedation (185+/-190 h vs 55.6+/-75.6 h; p<0.001). Similarly, the lengths of intensive care (13.5+/-33.7 days vs 4.8+/-4.1 days; p<0.001) and hospitalization (21.0+/-25.1 days vs 12.8+/-14.1 days; p<0.001) were statistically longer among patients receiving continuous i.v. sedation. Multiple linear regression analysis, adjusting for age, gender, severity of illness, mortality, indication for mechanical ventilation, use of chemical paralysis, presence of a tracheostomy, and the number of acquired organ system derangements, found the adjusted duration of mechanical ventilation to be significantly longer for patients receiving continuous i.v. sedation compared with patients who did not receive continuous i.v. sedation (148 h [95% confidence interval: 121, 175 h] vs 78.7 h [95% confidence interval: 68.9, 88.6 h]; p<0.001). CONCLUSION: We conclude from these preliminary observational data that the use of continuous i.v. sedation may be associated with the prolongation of mechanical ventilation. This study suggests that strategies targeted at reducing the use of continuous i.v. sedation could shorten the duration of mechanical ventilation for some patients. Prospective randomized clinical trials, using well-designed sedation guidelines and protocols, are required to determine whether patient-specific outcomes (eg, duration of mechanical ventilation, patient comfort) can be improved compared with conventional sedation practices.     

Diffuse and compact chromatin in the cell nuclei from tissues derived from different germ layers

Chromatin structure of nuclei of histogenetically distinct cells of humans and animals under normal and pathological courses of gestation was studied by the method of optic-structural computer analysis. A constant ratio of compact and diffuse chromatin is detected in nuclei of cells originating from all the germ layers. This ratio can change to a variable degree in cases of pathological gestation.