The mammalian testis accumulates lower levels of organochlorine chemicals compared with other tissues

Tissues were obtained from three separate experiments in order to quantify the tissue distribution of organochlorine chemicals that are thought to be potential reproductive toxicants in males: 1) Sprague Dawley rats received 1 microCi of 14C-Aldrin or 14C-Dieldrin (20.6 microCi/micromole) i.p. once a week for three weeks. One week and four weeks after the last injection, tissues were harvested and stored at -80 degrees C. Tissue 14C levels were quantified by scintillation spectrometry. 2) Cis- or trans-nonachlor (0, 0.25, 2.5, 25 mg/kg body weight) were administered daily in corn oil to male rats by gavage for 28 days. Tissues were harvested and frozen at -80 degrees C on the 29th day. Organochlorine residues were extracted and quantified by gas chromatography with electron capture detection. 3) Technical grade toxaphene (0, 0.1, 0.4 or 0.8 mg/kg body weight) was ingested daily by female cynomolgus monkeys of reproductive age for 18 months prior to being mated with control males. Dosing continued during pregnancy and lactation. Their infants received toxaphene via breast milk, and upon weaning, they ingested the same dose as their mothers for 48 to 49 weeks until, at 77 to 80 weeks of age, tissues were harvested and stored at -80 degrees C. Organochlorine residues were extracted and quantified as previously stated. In all three experiments, organochlorine residues in the testis were lower than in most of the other reproductive tract and nonreproductive tract tissues we examined. For example, testicular aldrin and dieldrin levels were <5% the epididymal content; testicular cis- and trans-nonachlor were <25% the epididymal content and, testicular toxaphene levels were <15% of the epididymal content. The reasons for the low degree of accumulation by the testis in comparison with other tissues are unknown. However, the lower testicular content may afford germ cells some protection from the potentially toxic effects of these chemicals.

An auroral flare at Jupiter

Jupiter's aurora is the most powerful in the Solar System. It is powered largely by energy extracted from planetary rotation, although there seems also to be a contribution from the solar wind. This contrasts with Earth's aurora, which is generated through the interaction of the solar wind with the magnetosphere. The major features of Jupiter's aurora (based on far-ultraviolet, near-infrared and visible-wavelength observations) include a main oval that generally corotates with the planet and a region of patchy, diffuse emission inside the oval on Jupiter's dusk side. Here we report the discovery of a rapidly evolving, very bright and localized emission poleward of the northern main oval, in a region connected magnetically to Jupiter's outer magnetosphere. The intensity of the emission increased by a factor of 30 within 70 s, and then decreased on a similar timescale, all captured during a single four-minute exposure. This type of flaring emission has not previously been reported for Jupiter (similar, but smaller, transient events have been observed at Earth), and it may be related directly to changes in the solar wind.

Photographic scoring of gingival overgrowth

BACKGROUND

A wide range of methods have been employed to determine the severity of gingival overgrowth resulting in uncertainty regarding the prevalence of the side-effect. There is no simple, non-invasive, objective, blind method for assessing gingival overgrowth.

AIM

This article aims to describe a method which is suitable for use in large-scale population studies.

MATERIALS AND METHODS

Photographs were taken of the anterior, buccal gingivae and teeth of 925 patients medicated with calcium channel blockers. In addition, each patient was ascribed a clinical gingival overgrowth score. 100 patients had repeat photographs, and a further 10 patients had alginate impressions taken. The models were scored for severity of gingival overgrowth using a described technique. The slides were scored using a modification of this technique.

RESULTS

When photographic and study model scores were compared, photographic scores were consistently higher, and as a result, a photographic score of 38.6% was considered to represent a significant overgrowth. There was good agreement between clinically determined scores and photographic scores (kappa=0.71).

CONCLUSIONS

The results indicate that this method is suitable for large-scale population studies where it also has the advantage of providing a continuous scale of gingival changes for subsequent statistical analysis.

A serological re-evaluation of acute non-A non-B hepatitis from the early 1970s

BACKGROUND

The epidemiology and natural history of recently discovered viruses, which may be responsible for cases of seronegative infectious hepatitis, are currently being investigated. Retrospective studies of stored sera can provide a historical perspective of these infections.

AIMS

To re-evaluate the serological, demographic and clinical characteristics of patients hospitalised in the early 1970s with acute hepatitis.

METHODS

The stored sera of 57 patients hospitalised between 1971 and 1974 with acute hepatitis, designated at that time as non-A non-B (NANB) hepatitis, were re-tested using commercially available enzyme-linked immunosorbent assays (ELISAs) for the presence of anti-hepatitis A virus (HAV) IgM, hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (HCV) IgG, and anti-hepatitis E virus (HEV) IgG. Stored sera from a group of 57 patients concurrently hospitalised for other conditions were also tested. Detailed records of the original epidemiological interviews were examined to compare patient demographics, risk factors for infectious hepatitis and clinical data for the NANB hepatitis group and an original control group of 604 hospitalised patients.

RESULTS

Serum from 15 of the 57 (26%) previously designated NANB hepatitis cases had elevated anti-HAV IgM and are likely to represent missed cases of hepatitis A. Thirteen (23%) of cases previously designated as NANB hepatitis had positive hepatitis C antibody tests. These patients were younger and significantly more likely to have used intravenous drugs than control patients. Three NANB hepatitis and two hospital control patients were anti-HEV IgG antibody positive. All of these individuals were born in, or had travelled to, developing countries. Serum from 27 (47%) of the NANB hepatitis patients were negative on all tests. These hepatitis non-A-E cases included children and elderly adults, but as a group were significantly more likely to have used intravenous drugs than hospitalised control patients.

CONCLUSION

Both HCV and probable non-A-E virus(es) were important causes of acute NANB hepatitis during the early 1970s.

A profile of alcohol and drug clients in New Zealand: results from the 1998 national telephone survey

AIMS

To describe the profile of clients seen across the broad spectrum of dedicated alcohol and drug treatment services in New Zealand.

METHODS

217 randomly selected alcohol and drug treatment workers in New Zealand were interviewed by telephone, yielding a randomly selected sample of 291 clients. Workers were asked to identify the age, gender, ethnicity, main substance use problem and geographical location of clients.

RESULTS

60% of clients were male, 28% were Maori, the mean age was 31 years and the largest group of clients were seen for alcohol related issues (45%), followed by cannabis (27%) and opioids (17%). None of these variables differed significantly across residential/non-residential services. Significant trends to emerge were: that Maori clients were more likely to live rurally and to be in treatment for cannabis use, women were more likely to be in treatment for benzodiazepine use and less likely for cannabis use, opioid users were more likely to be seen at Crown Health Enterprise funded services, and cannabis users were (on average) younger than other clients, while alcohol users were older.

CONCLUSIONS

Alcohol and drug treatment services are dominated by clients seeking assistance with alcohol and cannabis use problems. Women are not under-represented in this population. Maori are over-represented. This contrasts with the absence of Asian clients and an under-representation of Pacific Island clients. There are some significant variations in the types of drugs used by different demographic treatment seeking populations. In contrast, client differences across treatment settings are minimal.

In vitro inhibition and induction of human hepatic cytochrome P450 enzymes by modafinil

The ability of modafinil to affect human hepatic cytochrome P450 (CYP) activities was examined in vitro. The potential for inhibition of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4/5, and CYP4A9/11 by modafinil (5-250 microM) was evaluated with pooled human liver microsomes. Modafinil exhibited minimal capacity to inhibit any CYP enzyme, except CYP2C19. Modafinil inhibited the 4'-hydroxylation of S-mephenytoin, a marker substrate for CYP2C19, reversibly and competitively with a K(i) value of 39 microM, which approximates the steady-state C(max) value of modafinil in human plasma at a dosage of 400 mg/day. No irreversible inhibition of any CYP enzyme was observed, and there was no evidence of metabolism-dependent inhibition. The potential for induction of CYP activity was evaluated by exposing primary cultures of human hepatocytes to modafinil (10-300 microM). Microsomes were then prepared and assayed for CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4/5 activities. The mean activities of microsomal CYP1A2, CYP2B6, and CYP3A4/5 from modafinil-treated hepatocytes were higher (up to 2-fold) than those in the solvent-treated controls but were less than those produced by reference inducers of these enzymes. At high concentrations of modafinil (>/=100 microM), the mean activity of CYP2C9 was decreased (up to 60%) relative to that in the solvent controls. Overall, modafinil was shown to have effects on human hepatic CYP1A2, CYP2B6, CYP2C9, CYP2C19, and CYP3A4/5 activities in vitro. Although effects obtained in vitro are not always predictive of effects in vivo, such results provide a rational basis for understanding drug-drug interactions that are observed clinically and for planning subsequent investigations.

Effect of loading rate and hydration on the mechanical properties of the disc

STUDY DESIGN

The mechanical response of bovine intervertebral discs to axial compression at different loading rates and hydration levels was quantified.

OBJECTIVES

To quantify the effects of hydration and loading rate on the mechanical response of the intervertebral disc to compressive axial load.

SUMMARY OF BACKGROUND DATA

The disc is known to be viscoelastic, but there are few experimental data showing the effect of loading rate and hydration on its response to compression.

METHODS

Hydration level reduced by creep-loading from a fully hydrated starting point. Four groups were tested: Group A: fully hydrated (n = 5), six loading rates, from 0.3 kPa/sec to 30 MPa/sec; Group B: after 30 minutes of creep (n = 4); and Group C: after 2 hours of creep (n = 4) under a static load of 1 MPa, loading rates 3 MPa/sec, 30 kPa/sec, and 0.3 kPa/sec; Group D: at 5-minute intervals, during an 8-hour period of creep (n = 3) under a static load of 1 MPa, loading rate 3 MPa/sec. Data normalized by disc area and height: nominal stress, strain, and modulus calculated.

RESULTS

Group A: Modulus increased with load and rate of loading, with significant differences among the lower three loading rates. The highest three loading rates were significantly different from the lower rates, but not from each other. Group B: At the two higher loading rates, modulus was greater than in group A. At the lowest loading rate the modulus was similar to that in Group A. Group C: At the highest loading rate, the modulus was less than that of Groups A and B. At the lower two loading rates, the modulus was similar to that in Group A. Group D: The modulus increased in the first 30 minutes and decreased in the interval from 60 to 480 minutes.

CONCLUSIONS

Intervertebral disc compressive mechanical properties are significantly dependent on loading rate and hydration.

Maori and alcohol: a reconsidered history

OBJECTIVE

To document aspects of the history of alcohol use among Maori, with a particular focus on the period from 1840 to 1872 and to identify potential use of this knowledge in the development of strategies for the prevention and treatment of alcohol-related harm among Maori in contemporary New Zealand.

METHOD

A survey of the surviving documentation about alcohol in nineteenth-century New Zealand; materials were predominantly drawn from the writings of pakeha (non-Maori) missionaries, officials and travellers, as well as available statistical records.

RESULTS

Analysis of early written historical records suggests significant variation in the response of Maori to the introduction of alcohol in different parts of New Zealand during the period following European contact.

CONCLUSIONS

One stereotype that has arisen suggests Maori have been incapable of and/or unable to manage the production and use of alcohol. On the other hand, another commonly held belief has been that Maori supported abstinence or 'resisted alcohol' because they recognised its 'ruinous nature' and because it was contrary to traditional custom and practices. Historical information indicates that the Maori response to the introduction of alcohol was in fact diverse and for much of the nineteenth century alcohol was non-problematic for many Maori. This reinterpretation of the historical record can potentially empower contemporary Maori to take greater responsibility for the use of alcohol. It also challenges the negativity of the stereotypes generated by historical misinformation.

Unusual cluster of mild invasive serogroup C meningococcal infection in a university college

The objective of this study was to describe the epidemiology and public health response to an apparent cluster of Neisseria meningitidis serogroup C infection in university students in a residential college. A conventional epidemiological approach was taken, supported by routine and novel diagnostic techniques. Over the two days of 21-22 August 1997, three cases of suspected meningococcal infection were notified from a residential college complex at a university campus in the Sydney metropolitan area. Neisseria meningitidis was grown from throat swabs of all three cases, and was isolated from the blood of one case only. All three isolates were typed as C:2a:P1.5,2. Seroconversion was demonstrated by a novel method in the three cases. Rifampicin was given to all identified contacts. Forty-seven days after the index case, a 19 year old female living in the same complex was diagnosed with bacterial meningitis, and identified contacts given rifampicin. When this isolate was found to be group C, it was decided to vaccinate residents of the college complex. Genotyping and serotyping (C:2a:P1.5) later revealed the fourth isolate to be distinct from isolates from Cases 1-3. In conclusion the authors note that Australia's increasing capacity to type meningococcal strains is essential to understanding the epidemiology of this disease. Furthermore, typing information is of critical importance when decisions are made regarding mass vaccination. As early antibiotic treatment may inhibit isolation of the organism, development of novel approaches to diagnosis and typing should be supported.

A phase I/II study of carboplatin combined with hyperfractionated radiotherapy for brainstem gliomas

BACKGROUND

Brainstem gliomas often respond to radiotherapy but long term disease control is exceptional. The concomitant administration of a chemotherapy agent with radiosensitizing properties such as carboplatin may increase the efficacy of radiotherapy.

METHODS

A dose escalation schedule of carboplatin was devised to determine the maximum tolerated dose (MTD) of intravenous carboplatin when given on a twice-weekly schedule during a course of hyperfractionated, involved field radiotherapy (100 centigrays [cGy] twice daily to 7200 cGy). The starting dose was 20 mg/m(2) and the dose was increased by 15 mg/m(2) after every 3 patients provided no Grade 3 or 4 (according to the National Institutes of Health Common Toxicity Criteria) toxicity occurred. Magnetic resonance imaging (MRI) scans (brain and spine) were obtained before treatment and at the time of disease progression. Clinical entry criteria included an MRI scan demonstrating a diffuse intrinsic pontine tumor and a typical 2-3-month history of evolving cranial neuropathies and a gait disorder. Biopsy-confirmed evidence of a high grade glioma was required for nonpontine brain stem tumors.

RESULTS

A total of 34 patients were enrolled. The median age of the patients was 7.8 years (range, 3.6-15.4 years) and the median prodrome duration was 1.5 months (range, 0.25-36 months). The MTD was 110 mg/m(2) or a total cumulative dose of 1540 mg/m(2) over 7 weeks. The dose-limiting toxicity was hematologic. The median progression free survival was 8 months (range, 0-104+ months) and the overall survival was 12 months (range, 5-104+ months). At last follow-up there were 5 long term survivors (15%) who remained in continuous remission after a mean follow-up period of 79 months (range, 46-104 months). Fifteen of the 29 patients (52%) with recurrence and or disease progression developed leptomeningeal/intraaxial tumor spread beyond the local radiation field.

CONCLUSIONS

The cumulative MTD for carboplatin is 1540 mg/m(2) when administered concomitantly with involved field, hyperfractionated radiotherapy in a twice-weekly schedule for 7 weeks. Subsequent Phase II and III clinical trials can be conducted safely at this level.

Prevalence of gingival overgrowth induced by calcium channel blockers: a community-based study

BACKGROUND

The prevalence of gingival overgrowth induced by chronic medication with calcium channel blockers is uncertain. Although there have been several studies examining this question, the results are conflicting, with previous estimates ranging from 20% to 83%. There have been only 2 studies examining the prevalence of overgrowth induced by diltiazem and amlodipine, with estimates of 74% and 3.3%, respectively.

METHODS

The current study aimed to address the problems associated with these studies by examining a sample of patients taking one of 3 calcium channel blockers, who were drawn from a community-based population in northeastern England. Nine hundred eleven (911) subjects were recruited from general medical practices in the area. Of these, 442 were taking nifedipine, 181 amlodipine, and 186 diltiazem. In addition, 102 control subjects were examined. Drug and demographic data for each subject were recorded. The periodontal condition of all subjects was assessed including plaque index, papillary bleeding index, and a photograph of the anterior gingivae for subsequent analysis of overgrowth severity.

RESULTS

More than six percent (6.3%) of subjects taking nifedipine were seen to have significant overgrowth. This overgrowth was statistically greater than the amount of overgrowth seen in either of the other 2 drug groups or the control population. The prevalence of gingival overgrowth induced by amlodipine or diltiazem was not statistically significant when compared to the control group. The severity of overgrowth within the nifedipine group was found to be related to the amount of gingival inflammation and also to the gender of the subject, with males being 3 times as likely to develop overgrowth than females.

CONCLUSIONS

The prevalence of clinically significant overgrowth related to chronic medication with calcium channel blockers is low, i.e., 6.3% for nifedipine. Males are 3 times as likely as females to develop clinically significant overgrowth. The presence of gingival inflammation is an important cofactor for the expression of this effect.

Cytomegalovirus and human herpesvirus 6 both cause viral disease after renal transplantation

BACKGROUND

Systemic viral disease after renal transplantation, especially after treatment with OKT3 or antithymocyte globulin, has usually been attributed to cytomegalovirus (CMV) infection. Identification of human herpesvirus 6 (HHV6) has raised the possibility that infection or reactivation of this virus may also occur in the same setting.

METHODS

We thus examined the incidence of CMV and HHV6 infection in a prospective blinded consecutive series of 30 renal and renal/pancreas transplant patients, 22 of whom received OKT3, antithymocyte globulin, or both.

RESULTS

Clinical diagnosis of a viral syndrome was made in 15 patients. Three patients with only HHV6 DNA in urine or serum had fever and abnormal liver function but not neutropenia. All five CMV-seronegative patients who received positive kidneys developed moderate to severe disease with fever and neutropenia but also had HHV6 DNA in urine or serum. Seven CMV-seropositive patients developed disease, mostly after OKT3/antithymocyte globulin, but six shed both CMV and HHV6 in urine or serum. The simultaneous detection of both HHV6 and CMV DNA in either urine or serum was the strongest predictor of disease (and also the severity of disease), with an odds ratio of 99.0 (95% confidence intervals 5.4-1814, P<0.002).

CONCLUSION

Most systemic viral disease after renal transplantation may be due to either coinfection or reactivation of CMV and HHV6 together. A wider understanding of risk factors for severe viral disease in this setting may come from testing for both viruses in all donors and patients in both clinical practice and clinical trials.

Patterns of failure following treatment for medulloblastoma: is it necessary to treat the entire posterior fossa?

PURPOSE

Craniospinal radiation (CSRT) followed by a boost to the entire posterior fossa (PF) is standard postoperative therapy for patients with medulloblastoma. A large proportion of recurrences after treatment are local, with approximately 50-70% of recurrences occurring in the PF. It is unclear, however, whether these failures are occurring in the original tumor bed or outside the tumor bed, but still within the PF. With improved diagnostic imaging, better definition of tumor volumes, and the use of three-dimensional conformal therapy (3D CRT), we may be able to restrict the boost volume to the tumor bed plus a margin without compromising local control. This retrospective study analyzes the patterns of failure within the PF in a series of patients treated with radiation therapy (RT).

METHODS

From July 1986 through February 1996, 114 patients >18 months and <18 years with medulloblastoma were treated at the University of Michigan and Children's Hospital of Philadelphia, with RT following surgical resection. Of 114, 27 (24%) were found to have a recurrence and form the basis for this study. RT consisted of CSRT followed by a boost to the entire posterior fossa. Some patients received adjuvant chemotherapy. Patient's preoperative magnetic resonance imaging (MRI) and/or computerized tomography (CT) studies were used to compare the original tumor volume with the specific region of local relapse. Failure was defined as MRI or CT evidence of recurrence or positive cerebrospinal fluid cytology. Relapse was scored as local, if it was within the original tumor bed, and regional if it was outside of the tumor bed but still within the PF.

RESULTS

The median age of the 27 patients who relapsed was 8.6 years. Three patients were <3 years old. Of 27, 21 had disease localized to the PF. Of 26, 22 patients received chemotherapy during their treatment regimen; 1 patient did not have information on systemic treatment. The median dose of RT to the craniospinal axis was 32.5 Gy and to the PF was 55.2 Gy. The median time to recurrence was 19.5 months. Local failure within the tumor bed as any component of first failure occurred in 52% (14 of 27) of all failures, but as the solitary site of first failure in only 2 of 27 failures. Of 14 patients who failed in the tumor bed, 11 also failed in the spine, 8 of 14 also failed within the PF but outside the tumor bed, and 7 of 14 failed in all three locations. Local failure within the PF but outside the tumor bed as any component of first failure occurred in 41% (11 of 27) of all failures, but as the solitary site of first failure in only 1 of 27 failures. Of 11 patients who failed in the PF but outside the tumor bed, 9 also failed in the spine, 8 also failed within the tumor bed, and 7 failed in the all three locations. Of the failures outside the tumor bed but still within the PF, 7 of 11 failed in the leptomeninges, 1 in the brainstem parenchyma, and 3 in the PF parenchyma. Of 7 who failed in the PF leptomeninges, 6 also failed within the spine. Failure within the spine as any component of first failure occurred in 70% (19 of 27) of all failures and as the only site of first failure in 5 of 27 patients. Of 19 patients who failed in the spine, 11 also failed in the tumor bed, 9 also failed within the PF but outside the tumor bed, and 9 failed in the all three locations.

CONCLUSIONS

Leptomeningeal failure is a common component of failure and occurs in the leptomeninges of the PF, as well as the spine. Isolated tumor bed failure is a rarely observed event and occurred in only 2 of 27 failures described here. Similarly, parenchymal (nonleptomeningeal) failures in the PF but outside of the tumor bed were rare: 4 patients recurred in this manner, only 1 of whom was an isolated event without other sites of recurrence. Our data suggest that, when the entire PF is treated, very few failures develop in isolation in the PF outside the tumor bed. Further studies will be necessary to determine if RT to the tu

Posterior surgical treatment for the rheumatoid cervical spine

Twenty-six patients with rheumatoid disease affecting the cervical spine underwent surgical treatment for neck pain, neurological deficit, or both. Atlantoaxial subluxation (n=13), subaxial subluxation (n=7) and vertical migration of the odontoid (n=6) were treated. Arthrodesis with autologous bone was augmented with wire, Ransford loop, Hartshill rectangle or Magerl technique. Pain relief occurred in 92% of patients. Neurological deficit improved in 89% and was unchanged in the remainder. Radiographic stability was achieved in all but one patient. Posterior surgery effectively relieved pain and neurological deficit, and the complications encountered did not jeopardize the outcome.

[Comparison of outer membrane protein profiles of Vibrio sp]

The outer membrane protein (OMP) profiles of 32 Vibrio type strains have been compared. The major OMP profiles of different Vibrio species had a considerable heterogenecity. Most of the strains had 3-7 major OMPs, with molecular masses ranging between 91,000 and 14,000. Many strains had common major OMPs such as 54,000, 43,000 and 27,000. However, no common major OMPs in all Vibrio type strains had been found.

Auto-faxing imaging reports to referring physicians

One of the major service issues within Medical Imaging is delivering reports quickly to referring physicians. As an effort to improve service, Mount Sinai Hospital's Department of Medical Imaging implemented Auto-Fax to distribute imaging reports to physicians instead of the postal service. When a report is transcribed and then verified by the dictating radiologist, the radiology information system will automatically fax the result report to the referring physicians if subscribed to the Auto-Fax service. If not, the report will be printed and mailed out manually. A transmission log is kept recording the requisition number, time, date, fax number, number of pages, and transmission status of all reports faxed. The system will try three times to fax the report. If unsuccessful at all attempts, the report will be printed and sent out by mail. Referring physicians are required to sign an agreement that the receiving parties are responsible to ensure transmitted reports are kept confidential. Over 150 referring physicians have signed on for the service. Initial problems with missing cover pages, missing report pages, and reports not being received by physicians have been resolved. A recent survey of physicians receiving reports by Auto-Fax indicate that the service is very popular and has increased the speed with which transcribed report are received. Suggestions for improvement included faxing reports in batches, at specific times of the day, and directly to personal computers. Challenges reported included photocopying thermal paper faxes and sorting reports (for those offices with shared fax machines).

Validation of procedures for quantitative whole-body autoradiography using digital imaging

The objective of this study was to demonstrate that tissue concentrations of radioactivity derived by digital analysis of autoradiograms were comparable to values derived from direct sampling and analysis of tissues. In addition, we describe the preparation and calibration of standards for use in quantitative whole-body autoradiography. For this study, three male Long-Evans hooded rats were administered 14C radioactivity intravenously. The animals were sectioned for whole-body autoradiography, with concomitant sampling of blood and 16 selected tissues. After 3 weeks of film exposure, the optical densities of the resulting autoradiograms were analyzed with a RAS3000 digital imaging system to estimate tissue concentrations of radioactivity. These concentrations were then compared with those obtained by direct analysis of the tissue samples. The concentrations derived from digital analysis of the autoradiograms were very highly correlated with those determined from direct tissue analysis (r = 0.956). Linear regression analysis yielded a straight line with a slope of 0.97 and a goodness of fit (r2) of 0.913. This analysis suggested that there is an approximate 1:1 correlation between concentration values determined by the two methods. Marked differences between the values derived via the two techniques were observed for only three tissues. However, this subset of the data accounted for only 6% of the total data, and the differences were probably due to contamination from adjacent tissues during excision. Overall, the concentrations of radioactivity derived from digital analysis of the autoradiograms were comparable to those derived from direct analysis of tissue samples. The results indicated that the digital analysis procedure for film can serve as a valuable adjunct to conventional tissue analysis for radioactivity.

Molecular investigation into outbreak of HIV in a Scottish prison

OBJECTIVES

To support already established epidemiological links between inmates of Glenochil prison positive for HIV infection by using molecular techniques and thus provide evidence of the extent of acquisition during a recent outbreak of the disease resulting from needle sharing. To identify possible sources of the outbreak, and to demonstrate the ability of the methodology to make further links beyond the original outbreak.

DESIGN

Viral sequences obtained from the blood of HIV positive prisoners previously identified by standard epidemiological methods were compared with each other and with sequences from other Scottish patients.

SETTING

Glenochil prison for men, central Scotland.

SUBJECTS

Adult inmates and their possible contacts.

RESULTS

Phylogenetic analysis of viral sequences in two different genomic regions showed that 13 of the 14 HIV positive prisoners had been infected from a common source. Previous research had shown that six of these had acquired their infection in Glenochil; molecular evidence suggests that more than double this number were infected while incarcerated. Virus from two long term HIV positive patients who were in the prison at the time of the outbreak but who were not identified in the original or subsequent surveys was sufficiently different to make it unlikely that they were the source. A viral sequence from heterosexual transmission from one inmate showed the ability of these techniques to follow the infection through different routes of infection.

CONCLUSION

The number of prisoners infected with HIV during the 1993 outbreak within Glenochil prison was more than twice that previously shown. This shows the potential for the spread of bloodborne diseases within prisons by injecting drugs.

Toddler's fracture

Images

Open fractures of the tibia and femur in children

Forty-seven children with 32 open tibial fractures, 11 open femoral fractures, and six closed tibial fractures with compartment syndrome, which were surgically opened, were assessed for the time to union and incidence of nonunion and infection. Treatment varied with fracture severity and patient age. Tibial external fixators were supplemented by short-leg casts, and fixators were removed at an average of 7 weeks. No child required further surgery to achieve union. There was one (2%) delayed union and no nonunions. Three fractures (6%) developed infections. No pin-tract infections occurred in tibial fractures treated with external fixation with casting. The relation between age and time to union was statistically significant. In open fractures without segmental bone loss or soft-tissue loss requiring major reconstruction, bony healing can be expected within 6 months.

Evolution of zidovudine resistance-associated genotypes in human immunodeficiency virus type 1-infected patients

Substantial differences have been described in the response of individual patients to zidovudine (ZDV) therapy, both in the clinical impact and in virus load. Genotypic changes associated with the appearance of drug resistance may also be different or occur at different rates. We have obtained the nucleotide sequence of the RT domain of individual HIV-1 genomes extracted from 10 plasma and peripheral blood mononuclear cell (PBMC) samples donated by two haemophiliac patients before, during, and after long-term ZDV therapy. Although the plasma virus load was similar throughout, the order and timing of appearance of resistance-associated substitutions differed in the two patients. In patient p74, K70R appeared after 4 months, T215Y at 5.5 months, and M41L at 13 months. In p87, K70R also appeared at 4 months, but T215Y and K219Q were not observed until 18 months and M41L not at all. Much greater sequence change overall occurred in p74. The evolution of the viral population in that patient was dominated by the unique appearance of T215Y and subsequently M41L, with all sequences from the last time point being descended by a single path from the pretreatment samples. However, in p87, several different lineages of RT sequences were found to persist throughout treatment. We propose that these differences in outcome may be determined by differences in genetic background at sites other than the five generally considered to be associated with ZDV sensitivity.

Congenitally corrected transposition of the great arteries in the adult: functional status and complications

OBJECTIVES

We sought to assess the clinical outcome, functional status and complications of adult patients with congenitally corrected transposition of the great arteries.

BACKGROUND

Congenitally corrected transposition is a rare form of congenital heart disease, although survival into adult life may be expected. Little information is available on the long-term prognosis of these patients once they have reached adulthood. This study focuses exclusively on patients >18 years old followed up at a single tertiary referral center.

METHODS

The charts of all patients with a diagnosis of congenitally corrected transposition of the great arteries from the Toronto Congenital Cardiac Centre for Adults since 1985 were reviewed. Data were available for 52 patients, 26 of whom had undergone radionuclide angiography. Mortality, clinical and functional status, surgical procedures and complications were reviewed.

RESULTS

Thirteen patients (25%) died; age at death was 38.5 +/- 12.5 years (mean +/- SD). The current age of survivors is 32.7 years (range 18.2 to 54.3). Of the survivors, 17 had palliative procedures, and 25 had definitive repair, 11 of whom required reoperation. Left ventricle to pulmonary artery conduit replacement was necessary in seven patients. Eighteen patients have permanent pacemakers, nine of whom developed complete heart block perioperatively. Nine patients developed progressive atrioventricular (AV) block unrelated to operation. Supraventricular arrhythmias occurred in 15 patients. Progressive systemic AV valve regurgitation developed in 10 patients and endocarditis in 6.

CONCLUSIONS

Congenitally corrected transposition in the adult patient is not a benign condition. Late complications are common and warrant careful, long-term follow-up.