Adverse health effects among women living with heavy snorers

Women living with heavy snorers were more frequently affected by symptoms of insomnia, morning headache, daytime sleepiness, and fatigue than women living with non-snorers. Questionnaire data were collected from 1,032 women 30 to 64 years of age residing in Dalarna county, in mid-Sweden. There were indications of a "dose-response relationship" between the conjectured sound exposure and reported symptoms, regardless of whether the female herself snored. Sleeping in separate bedrooms did not seem to give the women any alleviation. The results point to a possible contributory cause of disturbed sleep, morning headache, and daytime sleepiness among women living with a snoring spouse. The results also indicate that prevention and treatment of snoring are important issues for the couple as well as for the snorer.

Bone mineral density in adults with Marfan syndrome

OBJECTIVES

Reduced bone mineral density (BMD) has been reported in pre-menopausal women and children with Marfan syndrome (MFS). The bone mineral status of adult men with MFS is unknown. The objective of this study was to determine the BMD of adult men and women with MFS.

METHODS

BMD (g/cm(2)) was measured by dual-energy X-ray absorptiometry (DXA) of the lumbar spine (L1-L4), femoral neck and total hip in 25 adults (12 male) who fulfilled the 1996 MFS diagnostic criteria. The results were compared with age- and sex-matched controls and expressed as S.D. from the population mean (z score).

RESULTS

Overall, BMD was significantly reduced in the lumbar spine (z = -0.42 +/- 0.97, P < 0.05), total hip (z = -0.57 +/- 0.88, P < 0.005) and femoral neck (z = -0.51 +/- 0.88, P < 0. 005). In women alone, BMD was reduced at the femoral neck (z = -0.53 +/- 0.95, P < 0.05) and at the hip (z = -0.64 +/- 0.77, P < 0.005). In men, BMD was reduced at the femoral neck (z = -0.48 +/- 0.84, P < 0.05) with a non-significant trend to lower BMD at the hip (z = -0. 49 +/- 1.01, P = 0.054) and lumbar spine (z = -0.59 +/- 1.02, P = 0. 09).

CONCLUSION

Axial BMD is lower than normal in Marfan adults. This reduction may contribute to fractures seen in the Marfan population.

The adenosine transporter of Toxoplasma gondii. Identification by insertional mutagenesis, cloning, and recombinant expression

Purine transport into the protozoan parasite Toxoplasma gondii plays an indispensable nutritional function for this pathogen. To facilitate genetic and biochemical characterization of the adenosine transporter of the parasite, T. gondii tachyzoites were transfected with an insertional mutagenesis vector, and clonal mutants were selected for resistance to the cytotoxic adenosine analog adenine arabinoside (Ara-A). Whereas some Ara-A-resistant clones exhibited disruption of the adenosine kinase (AK) locus, others displayed normal AK activity, suggesting that a second locus had been tagged by the insertional mutagenesis plasmid. These Ara-A(r) AK+ mutants displayed reduced adenosine uptake capability, implying a defect in adenosine transport. Sequences flanking the transgene integration point in one mutant were rescued from a genomic library of Ara-A(r) AK+ DNA, and Southern blot analysis revealed that all Ara-A(r) AK+ mutants were disrupted at the same locus. Probes derived from this locus, designated TgAT, were employed to isolate genomic and cDNA clones from wild-type libraries. Conceptual translation of the TgAT cDNA open reading frame predicts a 462 amino acid protein containing 11 transmembrane domains, a primary structure and membrane topology similar to members of the mammalian equilibrative nucleoside transporter family. Expression of TgAT cRNA in Xenopus laevis oocytes increased adenosine uptake capacity in a saturable manner, with an apparent K(m) value of 114 microM. Uptake was inhibited by various nucleosides, nucleoside analogs, hypoxanthine, guanine, and dipyridamole. The combination of genetic and biochemical studies demonstrates that TgAT is the sole functional adenosine transporter in T. gondii and a rational target for therapeutic intervention.

Xanthine phosphoribosyltransferase from Leishmania donovani. Molecular cloning, biochemical characterization, and genetic analysis

Xanthine phosphoribosyltransferase (XPRT) from Leishmania donovani is a unique enzyme that lacks a mammalian counterpart and is, therefore, a potential target for antiparasitic therapy. To investigate the enzyme at the molecular and biochemical level, a cDNA encoding the L. donovani XPRT was isolated by functional complementation of a purine auxotroph of Escherichia coli that also harbors deficiencies in the prokaryotic phosphoribosyltransferase (PRT) activities. The cDNA was then used to isolate the XPRT genomic clone. XPRT encodes a 241-amino acid protein exhibiting approximately 33% amino acid identity with the L. donovani hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and significant homology with other HGPRT family members. Southern blot analysis revealed that XPRT was a single copy gene that co-localized with HGPRT within a 4.3-kilobase pair (kb) EcoRI fragment, implying that the two genes arose as a result of an ancestral duplication event. Sequencing of this EcoRI fragment confirmed that HGPRT and XPRT were organized in a head-to-tail arrangement separated by an approximately 2.2-kb intergenic region. Both the 3.2-kb XPRT mRNA and XPRT enzyme were significantly up-regulated in Deltahgprt and Deltahgprt/Deltaaprt L. donovani mutants. Genetic obliteration of the XPRT locus by targeted gene replacement indicated that XPRT was not an essential gene under most conditions and that the Deltaxprt null strain was competent of salvaging all purines except xanthine. XPRT was overexpressed in E. coli and the recombinant protein purified to homogeneity. Kinetic analysis revealed that the XPRT preferentially phosphoribosylated xanthine but could also recognize hypoxanthine and guanine. K(m) values of 7.1, 448.0, and >100 microM and k(cat) values of 3.5, 2.6, and approximately 0.003 s(-1) were calculated for xanthine, hypoxanthine, and guanine, respectively. The XPRT gene and XPRT protein provide the requisite molecular and biochemical reagents for subsequent studies to validate XPRT as a potential therapeutic target.

Coupled chemical and mechanical reaction steps in a processive Neurospora kinesin

We show using single molecule optical trapping and transient kinetics that the unusually fast Neurospora kinesin is mechanically processive, and we investigate the coupling between ATP turnover and the mechanical actions of the motor. Beads carrying single two-headed Neurospora kinesin molecules move in discrete 8 nm steps, and stall at approximately 5 pN of retroactive force. Using microtubule-activated release of the fluorescent analogue 2'-(3')-O-(N-methylanthraniloyl) adenosine 5'-diphosphate (mantADP) to report microtubule binding, we found that initially only one of the two motor heads binds, and that the binding of the other requires a nucleotide 'chase'. mantADP was released from the second head at 4 s(-1) by an ADP chase, 5 s(-1) by 5'-adenylylimidodiphosphate (AMPPNP), 27 s(-1) by ATPgammaS and 60 s(-1) by ATP. We infer a coordination mechanism for molecular walking, in which ATP hydrolysis on the trailing head accelerates leading head binding at least 15-fold, and leading head binding then accelerates trailing head unbinding at least 6-fold.

Validation of a geologically based radon risk map: are the indoor radon concentrations higher in high-risk areas?

Since geographically coded information is frequently used in studies of the relationships between environmental factors and illness at the population level and by authorities for promotion of mitigation, knowledge about the validity of proxy measures is essential. This study was an evaluation of a geologically based map describing the risk for high radon levels, which was used by the municipal authorities to determine the necessity of remedial actions. Annual mean radon gas concentrations for a random sample of one-family homes selected from high-risk areas (n = 252) were compared with those of a random sample of homes from normal and low-risk areas (n = 259). No difference in geometric mean radon concentration was found between the areas, 101 Bq m(-3) and 103 Bq m(-3), respectively. The proportion of homes in each area with radon gas concentrations above the current Swedish administrative limit value for mitigation (400 Bq m(-3)) was similar, approximately 10%. We conclude that the radon risk map was unsuitable for identifying areas of concern. The findings also indicate that geologically based and geographically coded information as a proxy for human exposures can be safely used for scientific and administrative purposes only following validation.

Information before coronial necropsy: how much should be available?

AIM

To assess the amount and quality of information supplied before undertaking a coroner's necropsy, based on the supposition that insufficient information may adversely affect the quality of the necropsy.

METHODS

For a one year period (947 cases), sudden death reports from the coronial jurisdiction of South Yorkshire (West) were audited to assess the quality of information supplied. Seven specific items of information were sought: age, sex, occupation, date of death, location of the body, position of the body, date of last seeing a general practitioner, and relevant medical history. The results from necropsy and non-necropsy cases were compared.

RESULTS

Only 22.1% of reports contained all seven items of information. There was no difference between the amount of information supplied in necropsy and non-necropsy cases except about when the general practitioner last saw the deceased. An occupational history was not available in 40.4% of all deaths.

CONCLUSIONS

The quality of information supplied to the pathologist before necropsy may be suboptimal and could affect the thoroughness of the necropsy itself.

Splicing mutations in KCNQ1: a mutation hot spot at codon 344 that produces in frame transcripts

BACKGROUND

Long-QT syndrome is a monogenic disorder that produces cardiac arrhythmias and can lead to sudden death. At least 5 loci and 4 known genes exist in which mutations have been shown to be responsible for the disease. The potassium channel gene KCNQ1, previously named KVLQT1, on chromosome 11p15.5 is one of these.

METHODS AND RESULTS

We initially analyzed one family using microsatellite markers and found linkage to KCNQ1. Mutation detection showed a G to C change in the last base of exon 6 (1032 G-->C) that does not alter the coded alanine. Restriction digest analysis in the family showed that only affected individuals carried the mutation. A previous report suggested that a G to A substitution at the same position may act as a splice mutation in KCNQ1, but no data was given to support this hypothesis nor was the transcription product identified. We have shown by reverse-transcription polymerase chain reaction that 2 smaller bands were produced for the KCNQ1 gene transcripts in addition to the normal-sized transcripts when lymphocytes of affected individuals were analyzed. Sequencing these transcripts showed a loss of exon 7 in one and exons 6 and 7 in the other, but an in-frame transcript was left in each instance. We examined other families in whom long-QT syndrome was diagnosed and found another unreported splice-site mutation, 922-1 G-->C, in the acceptor site of intron 5, and 2 of the previously reported 1032 G-->A mutations. All these showed a loss of exons 6 and 7 in the mutant transcripts, validating the proposal that a consensus sequence is affected in the exonic mutations and that the integrity of the base at position 1032 is essential for correct processing of the transcript.

CONCLUSIONS

The 6 cases already reported in the literature with the 1032 G-->A transition, the novel 1032 G-->C transversion, and a recent G-->T transversion at the same base show that codon 344 is the second most frequently mutated after codon 341, suggesting at least two hotspots for mutations in KCNQ1.

Intra-alveolar haemorrhage in sudden infant death syndrome: a cause for concern?

BACKGROUND

The "Back to Sleep" campaign in 1991 resulted in a dramatic decrease in the incidence of sudden infant death syndrome (SIDS). The proportion of presumed SIDS deaths being actually suspicious deaths from airway obstruction is likely to have become relatively greater. There is usually little pathological evidence to suggest smothering, but intra-alveolar haemorrhage appears to be more prominent in cases where interference with the airway is suspected.

AIM

To attempt to quantify intra-alveolar haemorrhage to see whether it could be used as a marker to distinguish between smothering/overlaying and SIDS.

METHODS

Intra-alveolar haemorrhage was quantified using digital image analysis on haematoxylin/eosin stained sections taken from the lungs of 62 consecutive infants who had died suddenly and unexpectedly. Cases were initially classified according to the original cause of death. After quantitation, the case histories were critically reviewed. Three pathologists independently made microscopic assessments of the degree of intra-alveolar haemorrhage in the first 24 cases to see whether these accurately reflected the quantitative results.

RESULTS

73% of those infants with a history suggesting possible involuntary overlaying and 45% of those with a history suspicious of smothering had significant intra-alveolar haemorrhage (> 5% of total lung surface area assessed). From the history, the cause of death in 11 cases initially classified as SIDS would better have been given as "Unascertained." Simple microscopic assessments underestimated the true extent of the haemorrhage in 33% (8/24).

CONCLUSIONS

If a moderate degree (at least 5%) of pulmonary parenchymal haemorrhage is observed, this may be an indicator of airway obstruction for a significant period, either from overlaying or possibly smothering. The diagnosis of SIDS may be being used inappropriately in such cases.

Lytic Paget disease as a cause of orbital cholesterol granuloma

A case of histologically confirmed Paget disease of the orbit produced a lesion that appeared both clinically and histologically similar to a cholesterol granuloma. This case is unique because of the unusual location of the lesion, its presentation in a patient with no other manifestations of Paget disease, and the histological picture produced by the disease.

Intravenous therapy for women in labor: implementation of a practice change

BACKGROUND

Intravenous therapy for women in labor has been routinely administered in many North American hospitals since the 1950s. The purpose of this study was to evaluate a change in intravenous therapy practice.

METHODS

The evaluation study, using a posttest, quasi-experimental design, examined the responses of women in labor and nurses to a questionnaire. Proxy prestudy cohort data were used for comparison of some patient outcomes. The convenience sample comprised 219 women admitted to the labor and delivery unit of a community hospital in Toronto, Ontario, between August and October 1997.

RESULTS

Under the new intravenous therapy protocol, 26 percent of the women in labor did not receive intravenous therapy compared with 100 percent under the old protocol. The primary reasons for therapy were to enable administration of prescribed medication and bolus intravenous administration associated with epidural anesthesia. At the first after-delivery void, 61 percent of study women-65 percent of those who received intravenous therapy and 50 percent of those who received no intravenous therapy-tested negative for ketonuria. All 119 comments from nurses indicated comfort with their judgments related to the initiation of intravenous therapy.

CONCLUSIONS

The change in the intravenous therapy protocol was supported by the study findings. Nurses should increase patient education about drinking and eating adequately throughout labor if appropriate, and resuming adequate fluid and food intake as quickly as possible after childbirth.

Bruising in non-accidental head injured children; a retrospective study of the prevalence, distribution and pathological associations in 24 cases

Non-accidental head injury, be it shaking, impact(s) or a combination of the two, is characterised by subdural and/or subarachnoid haemorrhages with retinal haemorrhages, but minimal or absent external cranio-facial trauma. The classical assault scenario depicts the infant being gripped around the head, face, chest and abdomen and shaken or being gripped by a limb and swung. This gripping might be expected to leave physical evidence in the form of bruising. A study was undertaken to establish the prevalence, distribution and pathological association of external bruising in 24 cases of fatal non-accidental head injury in children. At autopsy, 17 cases had new external bruises, 15 old external bruises and 13, a combination of both. However, seven (29%) cases showed no fresh external bruising and five (21%) showed no external bruising at all. Thus, external bruising may be absent in children with fatal intracranial injury. The face was shown to be the commonest site of bruising followed by the forehead and buttocks. Limb, chest and abdominal bruising were found to be uncommon. Retinal haemorrhages were confirmed in 23 (96%) cases. It is hypothesised that bruising, when present, may be a result of abuse in the form of punches and slaps rather than due to gripping during the assault. We discuss why gripping does not necessarily result in external bruising.

Problems in the interpretation of hemorrhage into neck musculature in cases of drowning

To investigate the possible causes of unexplained hemorrhage into the neck musculature in deaths due to drowning, all cases of drowning between the years 1985 and 1995 examined by members of the Department of Forensic Pathology, University of Sheffield were reviewed. Cases were selected in which hemorrhage was found within the neck musculature but in which no apparent explanation for the hemorrhage, such as compression of the neck or trauma, was present. Eight cases were identified from a total of 99 deaths from drowning. Postmortem hypostasis was distributed in the back or diffusely in 6 cases and in the face in 3 cases. The degree of decomposition varied but was severe in only 1 case. A raised blood alcohol level was detected in 3 cases. Anterior neck compartment hemorrhage is probably due to hypostasis in a high proportion of cases. The Prinsloo and Gordon artifact may be an operative factor in at least some cases. Hemorrhage may result from violent neck movements during the process of drowning. Apparent "bruising" of the neck musculature does not always indicate compression of or trauma to the neck.

Effect of feedback signal and psychological characteristics on blood pressure self-manipulation capability

Blood pressure presentation mode and personality are likely to influence biofeedback outcome. Thirty-six normotensive subjects were randomly assigned to visual or auditory continuous systolic feedback. "Distracting speech" and "broad band noise" were also superimposed and the effect on the biofeedback response was investigated. Psychological influence was also investigated. Systolic pressure reduction of 4 +/- 4.3 mmHg (visual, p = .04) and 5 +/- 5.5 mmHg (visual + auditory, p = .03) were achieved compared with auditory feedback (2 +/- 4.7 mmHg), which was less effective. The addition of noise or speech had no effect on the systolic response, but speech adversely affected diastolic reduction (p = .04). Mood (p = .003) was associated with systolic lowering, whereas increased trait anxiety (p = .06) and expectation (p = .03) had trends for opposite effects. Increased anger-hostility, state-anxiety, and expectation (p = .06) had links with systolic raising capability. We conclude that feedback modality and psychological characteristics have implications for studies investigating blood pressure manipulation capability.

Air weapon fatalities

AIMS

To describe characteristics of a series of people accidentally and deliberately killed by air powered weapons.

METHODS

Five cases of fatal airgun injury were identified by forensic pathologists and histopathologists. The circumstances surrounding the case, radiological examination, and pathological findings are described. The weapon characteristics are also reported.

RESULTS

Three of the victims were adult men, one was a 16 year old boy, and one an eight year old child. Four of the airguns were .22 air rifles, the other a .177 air rifle. Two committed suicide, one person shooting himself in the head, the other in the chest. In both cases the guns were fired at contact range. Three of the cases were classified as accidents: in two the pellet penetrated into the head and in one the chest.

CONCLUSIONS

One person each year dies from an air powered weapon injury in the United Kingdom. In addition there is considerable morbidity from airgun injuries. Fatalities and injuries are most commonly accidents, but deliberately inflicted injuries occur. Airguns are dangerous weapons when inappropriately handled and should not be considered as toys. Children should not play with airguns unsupervised.

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern since deterioration in the health of the unemployed is often anticipated. However, for some groups, such as miners, unemployment might improve health due to a cessation of potentially harmful occupational exposures. This study evaluates the health of 79 miners in one Swedish iron-ore mine, and 226 age-matched controls from the general population, during one year after the closure of the mine. The participants received a questionnaire regarding medical history and subjective symptoms at the beginning of the study period, and after one year. Statistically significant negative effects on self-reported health attributable to unemployment were not found, although neuropsychiatric symptoms were more common among the unemployed miners. The miners reported a statistically significant improvement in grip force (p = 0.031). They had a significantly higher prevalence of symptoms associated with mining related exposures when compared with the population controls; pain in the upper extremities [relative risk (RR) = 2.27, 95% confidence interval (CI) = 1.44-3.59), back pain (RR = 1.84; CI = 1.23-2.75), vasospastic disease of the fingers (RR = 2.05; CI = 1.18-3.57) and obstructive respiratory symptoms (attacks of dyspnea and wheezing: RR = 3.67; CI = 1.16-11.6).

Occupational exposure to organic solvents and sleep-disordered breathing

STUDY OBJECTIVE

To investigate whether people with occupational exposure to organic solvents have a higher prevalence of obstructive sleep apnea syndrome (OSAS) than the general population and to examine the relationship between snoring and exposure to organic solvents.

DESIGN AND PARTICIPANTS

Consecutive patients, aged 30-64 years, referred during a 3-year period to the sleep laboratory at Avesta Hospital, Sweden, because of suspected OSAS made up the patient groups. Following admission, patients underwent a simplified sleep apnea investigation and were divided into two groups, OSAS (n = 320) and snorers (n = 443). A random sample of 296 men and 289 women aged 30-64 years obtained from a register of all country residents maintained by the county tax authority served as referents (controls). Both patients and referents responded to two questionnaires, including questions about occupation, exposure to organic solvents, and other chemical and physical agents.

RESULTS

Men with OSAS or snoring and women with snoring had more often been occupationally exposed to organic solvents than the referents, showing an almost twofold increase in risk for those exposed during whole workdays. For men, the risk of OSAS or snoring increased with increasing exposure.

CONCLUSION

The result indicates that occupational exposure to organic solvents might cause sleep apnea. A new observation is that even snoring could be caused by exposure to organic solvents. It is important to elucidate whether exposure to organic solvents is a cause of OSAS, because such a finding may have important implications for prevention and treatment of sleep disturbances.

Trisomy 5q12-->q13.3 in a patient with add(13q): characterization of an interchromosomal insertion by forward and reverse chromosome painting

We report on a patient with azoospermia, mild mental retardation, and minor physical anomalies. Chromosome analysis demonstrated the presence of additional material on the long arm of one chromosome 13. Forward chromosome painting using chromosome-specific libraries showed an insertion of material from chromosome 5. Further characterization with flow sorting of the aberrant chromosome and amplification by DOP-PCR followed by reverse chromosome painting showed specific trisomy of 5q12-->q13.3.

Polycystin expression during embryonic development of human kidney in adult tissues and ADPKD tissue

Normal renal tissue, ranging from 8 weeks' gestation to full term to adult, was probed with polyclonal antibodies raised to peptide epitopes within the translated PKD1 gene sequence. Three antibodies were studied, all of which gave similar results. Renal tissue from patients with autosomal dominant polycystic kidney disease (ADPKD) and samples from normal adult liver, heart, brain, skeletal muscle and lymph node were also studied. Tissue staining demonstrated that the pattern of polycystin expression changed with gestational age in normal kidney. Whereas the precursors to the renal excretory unit were stained at 12 weeks, and the proximal and distal convoluted tubules stained to differing degrees throughout development, the glomeruli were poorly stained until full term and also in the adult. Extrarenal tissue stained in both adult and juvenile samples, with the exception of lymph node, which remained unstained. The intensity of polycystin staining increased in ADPKD renal tissue. The widespread distribution of polycystin was consistent with the systemic nature of ADPKD and the role of epithelial cells in the disease.