Respiratory acidosis and subcutaneous emphysema during laparoscopic cholecystectomy

A case is presented of a healthy 69-yr-old woman who underwent elective laparoscopic cholecystectomy under general anaesthesia. As surgery proceeded she developed hypercapnia (arterial blood PaCO₂ = 100 mmHg) and a related respiratory acidosis (arterial blood pH 7.07). The cause was attributed to subcutaneous insufflation and absorption of CO₂, directly related to the surgical pneumoperitoneum.     

Family size, infections, and asthma prevalence in New Zealand children.

We conducted a prevalence case-control study to investigate the relation between family composition, infection, and development of asthma at age 7-9 years. Potential cases (399) and controls (398) were selected from the Wellington, NZ, arm of the International Study of Asthma and Allergies in Childhood, a population-based prevalence study. Further screening questions restricted cases to children with a diagnosis of asthma and current medication use (N = 233) and restricted controls to children without a history of wheezing and no diagnosis of asthma (N = 241). After controlling for confounders (including infections, atopy, and socioeconomic status), family size was strongly related to asthma. Having no siblings [prevalence odds ratio (POR) = 2.51; 95% confidence interval (CI) = 1.05-6.01] or one sibling (POR = 1.86; 95% CI = 1.14-3.03) was associated with an increased risk of asthma compared with having more than one sibling. Parent-reported rubeola infection (and possibly other similar viral exanthems) was independently associated with a decreased risk of asthma (POR = 0.48; 95% CI = 0.27-0.83), but reported pertussis infection (POR = 1.57; 95% CI = 0.58-4.24) and day care attendance in the first year of life (POR = 1.81; 95% CI = 0.93-3.51) were not strongly associated with increased risks of asthma.     

The New Zealand Socioeconomic Index: developing and validating an occupationally-derived indicator of socio-economic status

OBJECTIVE: Following revision of the international standard classification (ISCO88), to update and validate on health data an occupationally derived indicator of socio-economic status (SES) adapted to changing occupational and demographic conditions. METHOD: The development of the New Zealand Socioeconomic Index (NZSEI) is based on a 'returns to human capital' model of the stratification process and uses data from the 1991 New Zealand Census (n = 1,051, 926) to generate scores for 97 occupational groups. The construct validation of the scale is carried out on data from the 1992-93 nationwide Household Health Survey (n = 3,000) using three health indicators (self-assessed health, cigarette smoking, general practitioner visits). RESULTS: In general, the results are consistent with expected socio-economic patterns drawn from the literature for the three indicators. CONCLUSIONS: While further work is required on a number of methodological and conceptual issues, the NZSEI provides a robust, standardised and internationally comparable occupational scale of SES for both males and females in either full- or part-time employment. IMPLICATIONS: The NZSEI can be used on routinely collected occupational data. It has a clear conceptual rationale, updates existing SES scales, and provides a link to international standards in SES and occupational classification.     

Atypical post-translational modification and targeting of a Schistosoma mansoni surface receptor, a member of the transforming growth factor beta receptor family of cell surface receptors

The surface membrane of the intravascular parasite Schistosoma mansoni is composed of not one but two closely apposed lipid bilayers which overlie a syncytial cellular layer, known as the tegument or neodermis. To gain insights into how membrane proteins are transported to and displayed on this unusual surface structure, we have investigated the post-translational modification and targeting of SmRK-1, a receptor and type I membrane protein expressed on the parasite surface, using heterologous expression systems. While SmRK-1 enters the secretory pathway in these systems, our data indicate that the SmRK-1 N-terminal signal peptide is either not cleaved by signal peptidase or is only eleven amino acids long or less. Retention of the signal peptide is accompanied by N-linked glycosylation of an asparagine residue within the predicted signal peptide. The SmRK-1 signal peptide is not capable of directing another cytoplasmic protein to the secretory pathway, suggesting that the signal for insertion of the SmRK-1 extracellular domain into the endoplasmic reticulum resides elsewhere in the protein. Further, SmRK-1 is inefficiently transported to the cell surface in mammalian cells, suggesting that the schistosome neodermis possesses specialized systems for receptor targeting and localization.     

Chronic supranigral infusion of BDNF in normal and MPTP-treated common marmosets

Summary. BDNF or vehicle were administered by unilateral supranigral infusion in normal and chronically lesioned MPTP-treated common marmosets (Callithrix jacchus) for four weeks and locomotor activity, disability and response to apomorphine were assessed with nigral TH, GFAP and GAD immunoreactivity and striatal [³H]mazindol autoradiography. Selective contraversive orientation and ipsilateral neglect evolved in MPTP-treated marmosets receiving BDNF with no significant difference in disability or locomotor activity when compared to the vehicle-infused group. Apomor-phine produced an ipsiversive rotational bias in BDNF-treated animals. In normal animals infused with BDNF contralateral neglect, ipsiversive turning, postural instability and ataxia rapidly evolved. In MPTP-treated marmosets BDNF caused increased ipsilateral striatal [³H]mazindol binding with increased somatic size and staining intensity in GAD-immunoreactive cells and a 10–20% loss of nigral TH-immunoreactive cells with increased GFAP staining. In normal common marmosets, both vehicle and BDNF infusion decreased nigral TH-immunoreactivity. Chronic supranigral infusion of BDNF alters motor behaviour and spatial attention in MPTP-treated marmosets which may reflect altered function in residual nigral dopaminergic neurons and brainstem GABAergic neurons and in normal animals produces behavioural and histological signs of nigrostriatal hypofunction. Received September 1, 1998; accepted December 17, 1998     

Multifocal intraocular lenses

Since the publication of my last article in Current Opinion in Ophthalmology in 1991 (2:33-34), the use of multifocal intraocular lenses (IOLs) has not gained general acceptance among ophthalmologists. Despite this situation, major IOL companies have continued to invest in clinical trials of new designs. Recently, large optic multifocal lenses used mainly with extracapsular extraction provided good results, with 94% to 100% of best-corrected cases having distance correction of 20/40 vision or better; 77% to 100% similarly had J3 near vision or better, and approximately 52% to 63% of patients became eyeglass independent. Between 50% to 80% of eyes in which 20/40 vision or better was obtained and in which J2 or better resulted were unaided. However, all multifocal lens designs showed some reduction in contrast sensitivity compared with monofocal designs using Regan charts and Vistech 6500 tests. Contrast sensitivity loss was probably only significant when reading very small print or in low-contrast light. Small-incision surgery with phacoemulsification and more accurate IOL power calculations have made the goal of emmetropia more possible. Also, less eyeglass dependence with the use of multifocal IOLs is a more realistic expectation.