Associations between family history of cancer and genes coding for metabolizing enzymes (United States)

OBJECTIVE

Family history of cancer has been a useful tool to identify highly penetrant genes. However, the association between family history and low-penetrance genes that are prevalent in the population, is less well understood. While epidemiologists have studied low-penetrance genes in association studies at the population level, geneticists have often favored family studies to identify low-penetrance genes in the same manner that these families have been used to identify high-penetrance genes. In this study, we evaluated the association between family history of cancer and molecular variants of three genes: N-acetyltransferases (NAT2), glutathione-S-transferases (GSTM-1), and methylenetetrahydrofolate reductase (MTHFR). These genes were examined because of their plausible functional significance and their association with cancer risk in some studies.

METHODS

In a large multi-centered study of colon cancer, reported family history of cancer in first-degree relatives was used to classify cases and controls separately as having a family history of colorectal cancer, hormone-related cancers, smoking-related cancers, prostate cancer, and any cancer.

RESULTS

With three weak exceptions, we did not observe significant associations between any of these genes and family history of cancer. The ability of family history to positively predict the presence of variants of low-penetrance genes that may carry an elevated risk ranged from 41% to 60%; low-penetrance variants accurately predicted a family history of cancer 9 to 17% of the time. Assessment of the likelihood of having a family history of cancer given the combination of genetic and environmental factors, showed that those who smoked 20 or more cigarettes per day were more likely to have a family history of a smoking-related cancer irrespective of genotype.

CONCLUSIONS

People with a family history of cancer are not more likely to have a variant of low-penetrance genes than those without a family history of cancer. Family studies may not be efficient methods to study low-penetrance genes.

Computer recording of standard tests of visual neglect in stroke patients

OBJECTIVE

To determine whether a computer-based method for recording standardized assessment of neglect identifies abnormalities in the 'process' as well as in the 'outcome' of such tasks.

DESIGN

Prospective sequential assessment of patients admitted to a stroke rehabilitation unit.

SUBJECTS

All consecutive patients with right-sided cerebrovascular accident confirmed on computerized tomography (CT) scan including 30 patients with neglect, 57 patients without neglect. An age-matched control group of 13 subjects.

INTERVENTION

All patients were tested using the standard Rivermead Behavioural Inattention Test (BIT) and by computer recording of two standard tests for assessing neglect (line bisection and Albert's test). Age-matched controls were tested using computer recording of the two standard tests.

MAIN OUTCOME MEASURES

Neglect was defined using the BIT with a cut-off score of 129. Computer recording measured the 'outcome' of tasks, i.e. the deviation from midline and omissions in cancellation, as well as the 'process' of tasks, i.e. time between cancellations, components of cancellation time including premovement, movement and drawing time, and the starting point for cancellation.

RESULTS

The computer recording identified significant differences in 'outcome' and 'process' which distinguished neglect from non-neglect patients. There were significant differences between non-neglect patients and age-matched controls with regard to 'process' measures but not with regard to 'outcome' measures.

CONCLUSIONS

Computer recording of standard tests for assessing neglect identifies novel impairments with regard to the process of carrying out tasks. These impairments may be used to investigate changes in neglect with time, the response of neglect to treatment and to explore further the neuropsychological changes associated with neglect in stroke patients.

Integrated designs for gene discovery and characterization

Recent advances, including near completion of the human genome map, ever improving high-throughput technologies, and successes in discovering chronic disease-related genes, have stimulated the further development of genetic epidemiology. The primary mission of genetic epidemiology is to discover and characterize genes, whether independent of or interactive with environmental factors, that cause human diseases. To accomplish such a mission, genetic epidemiology needs to integrate both genetic and epidemiologic approaches. One of the challenges facing such an integrated approach is the identification of study designs that are efficient for both gene discovery and characterization. Because designs for gene discovery alone and designs for gene characterization alone have been elaborated in the other two panels, the focus of this paper is to describe those designs that may be useful for discovery and characterization jointly, including case-family and case-control-family designs. Examples of integrated designs are described, and studies of breast cancer conducted at the Fred Hutchinson Cancer Research Center are used for illustration. Finally, related analytic issues are also discussed.

Evaluation of the PuriLens contact lens care system: an automatic care system incorporating UV disinfection and hydrodynamic shear cleaning

PURPOSE

This study evaluates lens care using the PuriLens System, an advanced way to clean and disinfect soft hydrophilic lenses using subsonic agitation and UV radiation, respectively.

METHODS

A two-period crossover lens cleaning and safety investigation was conducted using 80 patients. Disinfecting efficacy was tested in accordance with standard FDA protocols. Lens compatibility was studied with Group I and Group IV lenses during the equivalent of a 6-month care regimen by measuring: lens power, base curve, wet diameter, refractive index, clarity, and tint. Safety was evaluated through slit-lamp findings, wearing time, comfort, and visual acuity.

RESULTS

The mean wearing time of patients in the study was 13.79 hours. No slit lamp findings greater than grade 2 were noted. Visual acuity was 20/25 or better in 92.5% of examinations. None of the patients lost more than two lines of acuity. Lens surface evaluation showed no deposits (grade 0) to very slight deposits (grade 1) in 94.4% of examinations. Lenses cleaned with the PuriLens System were cleaner by a statistically significant margin (P=0.02) compared to lenses digitally cleaned with a leading multi-purpose solution (ReNu, Bausch & Lomb). Overall, neither the Group I nor Group IV lenses were affected after 180 cleaning cycles.

CONCLUSIONS

The PuriLens System provides automatic lens care compliance, superior antimicrobial efficacy, and eliminates the need for daily digital cleaning.

Population-based family study designs: an interdisciplinary research framework for genetic epidemiology

Most complex traits such as cancer and coronary heart diseases are attributed either to heritable factors or to environmental factors or to both. Dissecting the genetic and environmental etiology of complex traits thus requires an interdisciplinary research strategy. Genetic studies generally involve families and investigate familial aggregations of traits, segregation of major disease genes, and locations of disease genes on the human genome, the latter of which can be identified via linkage analysis. Epidemiologic studies often use population-based case-control studies to establish the role of specific environmental factors. Integrating both objectives, genetic epidemiology is to assess the associations of environmental factors with disease status, to quantify the aggregation of cases within families, to characterize putative disease genes via segregation analysis, and to localize disease genes via linkage analysis with genetic markers. To accomplish these objectives through designed studies, we propose a class of population-based family study designs, which are formed by choosing among sampling designs at three stages. The objectives of sampling at these three stages are 1) combined aggregation and association analysis, 2) combined segregation, aggregation, and association analysis, and 3) combined linkage, segregation, aggregation, and association analysis. These designs form an interdisciplinary research framework for genetic epidemiology. Our preliminary exploration of this framework and related analytic methods indicates that population-based family study designs retain the efficiency of linkage analysis for localizing disease genes without losing the property of being population-based, and they will therefore allow an assessment of a joint contribution of genetic and environmental factors to complex traits.

Factors affecting the dissolution and degradation of oriental mustard-derived sinigrin and allyl isothiocyanate in aqueous media

Sinigrin, the predominant glucosinolate in the oriental mustard Brassica juncea, is mainly degraded upon the enzymatic action of myrosinase under normal conditions to give allyl isothiocyanate (AITC) in an aqueous media. Because AITC is considered to be the principal nematicidal ingredient in B. juncea, its stability in aqueous media is an important issue in achieving efficient nematode control. Pure sinigrin and AITC were found to be relatively stable in buffered water in the pH range of 5.00-7.00 but less stable at pH 9.00. Both sinigrin and AITC were more stable in soil water (supernatant of a 1:1 water/air-dried soil mixture) than in buffered water at the same pH range of 5.00-9.00. Sinigrin dissolved from the mustard bran or ground seed into water very quickly and was degraded by codissolved myrosinase to AITC. The AITC that formed from the degradation of sinigrin was found to be more stable in the soil water than in the buffered water. Buffer capacity was considered to be one of the factors that contributed to the stabilization of AITC in the soil water, but other unknown factors from both bran or seed and soil may also have contributed to the stabilization.

Differential engraftment of genetically modified CD34(+) and CD34(-) hematopoietic cell subsets in lethally irradiated baboons

OBJECTIVE

To test gibbon ape leukemia virus (GALV) pseudotype vector transduction of marrow subpopulations that contribute to hematopoietic reconstitution in vivo.

MATERIALS AND METHODS

Autologous CD34(+) Lin(-), CD34(+) Lin(+), and CD34(-) Lin(-) marrow cells, transduced by coculture with PG13/LN, PG13/LNX, and PG13/LNY vector-producing cells, respectively, were transplanted in three female baboons. Two female baboons also were transplanted with fresh allogeneic CD34(-)Lin(-) marrow cells from MHC-matched male siblings and, to ensure survival, with autologous CD34(+)Lin(-) and CD34(+)Lin(+) marrow cells transduced with PG13/LN and PG13/LNX, respectively. The LN, LNX, and LNY vectors are identical except for different length sequences at the 3' end of the bacterial neomycin phosphotransferase (neo) gene.

RESULTS

LN(+) and LNX(+) cells from CD34(+)Lin(-) and CD34(+)Lin(+) cells, respectively, but no LNY(+) from CD34(-)Lin(-) cells were detectable in blood and marrow of all animals after transplant. LN(+), CD34(+)Lin(-) cells contributed to reconstitution of the T, B, and myeloid lineages. LNX(+), CD34(+)Lin(+) cells contributed only to B and myeloid lineages. Male cells, CD34(-)Lin(-), were detected by polymerase chain reaction in blood and marrow of the two allogeneic transplanted animals at estimated frequencies of </=0.001% 1 month after transplant in both animals. Male cells became undetectable in one animal and have remained detectable, with declining frequency, in the other for more than 15 months. In this animal, no male CD34(+) or colony-forming cells have been detected.

CONCLUSIONS

CD34(+)Lin(-) and CD34(+)Lin(+) marrow cells can serve as targets for GALV pseudotype retrovirus-mediated gene transfer. CD34(+)Lin(-) cells contribute to reconstitution of all hematopoietic lineages. Autologous CD34(-)Lin(-) cells were either not transduced by GALV pseudotype retrovirus vectors using current approaches or did not contribute significantly to reconstitution, as suggested by allogeneic transplants.

Severe liver degeneration and lack of NF-kappaB activation in NEMO/IKKgamma-deficient mice

Phosphorylation of IkappaB, an inhibitor of NF-kappaB, is an important step in the activation of the transcription factor NF-kappaB. Phosphorylation is mediated by the IkappaB kinase (IKK) complex, known to contain two catalytic subunits: IKKalpha and IKKbeta. A novel, noncatalytic component of this kinase complex called NEMO (NF-kappaB essential modulator)/IKKgamma was identified recently. We have generated NEMO/IKKgamma-deficient mice by gene targeting. Mutant embryos die at E12.5-E13.0 from severe liver damage due to apoptosis. NEMO/IKKgamma-deficient primary murine embryonic fibroblasts (MEFs) lack detectable NF-kappaB DNA-binding activity in response to TNFalpha, IL-1, LPS, and Poly(IC) and do not show stimulus-dependent IkappaB kinase activity, which correlates with a lack of phosphorylation and degradation of IkappaBalpha. Consistent with these data, mutant MEFs show increased sensitivity to TNFalpha-induced apoptosis. Our data provide in vivo evidence that NEMO/IKKgamma is the first essential, noncatalytic component of the IKK complex.

A preliminary investigation into the use of virtual environments in memory retraining after vascular brain injury: indications for future strategy?

PURPOSE

In a preliminary investigation of the use of Virtual Environments (VEs) in neurorehabilitation, this study compares the effects of active and passive experience of a VE on two types of memory in vascular brain injury patients and controls.

METHOD

Forty-eight patients with vascular brain injury and 48 non-impaired control participants were randomly assigned to active and passive VE conditions. The active participants explored a virtual bungalow seeking a particular object; the passive participants observed, but did not control movement through the VE, also seeking the object. Afterwards, both active and passive participants completed spatial recognition and object recognition tests.

RESULTS

Expectedly, the patients were impaired relative to the controls but were able to perform the virtual tasks. Active participation in the VE enhanced memory for its spatial layout in both patients and controls. On object recognition, active and passive patients performed similarly, but passive controls performed better than active controls.

CONCLUSIONS

The findings are discussed in relation to their implications for memory rehabilitation strategies.

Developing algorithms to enhance the sensitivity of cancellation tests of visuospatial neglect

We describe a set of algorithms that enhance the sensitivity of cancellation tests used in assessing visuospatial neglect. The algorithms can be readily implemented on a computer and can provide temporal and nontemporal data on strategies used during cancellation. We also present preliminary results from a group of 68 right-hemisphere brain-damaged patients and 12 age-matched control participants, which demonstrate the clinical significance of the measures we have defined.

Should sexual partners of women with bacterial vaginosis receive treatment?

Bacterial vaginosis is the most prevalent infectious cause of vaginitis. It is associated with significant morbidity, particularly in pregnant women and following gynaecological operations. Cure is difficult. There is some controversy over whether treating sexual partners of affected women can improve cure rates. This paper provides a critical appraisal of the evidence for simultaneously treating the male partner of women affected by bacterial vaginosis. Unfortunately, no evidence was found supporting the treatment of partners of women affected by bacterial vaginosis.

Guidelines for management of hypertension: report of the third working party of the British Hypertension Society

Use non-pharmacological measures in all hypertensive and borderline hypertensive people. Initiate antihypertensive drug therapy in people with sustained systolic blood pressures (BP) >/=160 mm Hg or sustained diastolic BP >/=100 mm Hg. Decide on treatment in people with sustained systolic BP between 140 and 159 mm Hg or sustained diastolic BP between 90 and 99 mm Hg according to the presence or absence of target organ damage, cardiovascular disease or a 10-year coronary heart disease (CHD) risk of >/=15% according to the Joint British Societies CHD risk assessment programme/risk chart. In people with diabetes mellitus, initiate antihypertensive drug therapy if systolic BP is sustained >/=140 mm Hg or diastolic BP is sustained >/=90 mm Hg. In non-diabetic hypertensive people, optimal BP treatment targets are: systolic BP <140 mm Hg and diastolic BP <85 mm Hg. The minimum acceptable level of control (Audit Standard) recommended is <150/<90 mm Hg. Despite best practice, these levels will be difficult to achieve in some hypertensive people. In diabetic hypertensive people, optimal BP targets are; systolic BP <140 mm Hg and diastolic BP <80 mm Hg. The minimum acceptable level of control (Audit Standard) recommended is <140/<90 mm Hg. Despite best practice, these levels will be difficult to achieve in some people with diabetes and hypertension. In the absence of contraindications or compelling indications for other antihypertensive agents, low dose thiazide diuretics or beta-blockers are preferred as first-line therapy for the majority of hypertensive people. In the absence of compelling indications for beta-blockade, diuretics or long acting dihydropyridine calcium antagonists are preferred to beta-blockers in older subjects. Compelling indications and contraindications for all antihypertensive drug classes are specified. For most hypertensives, a combination of antihypertensive drugs will be required to achieve the recommended targets for blood pressure control. Other drugs that reduce cardiovascular risk must also be considered. These include aspirin for secondary prevention of cardiovascular disease, and primary prevention in treated hypertensive subjects over the age of 50 years who have a 10-year CHD risk >/=15% and in whom blood pressure is controlled to the audit standard. In accordance with existing British recommendations, statin therapy is recommended for hypertensive people with a total cholesterol >/=5 mmol/L and established vascular disease, or 10-year CHD risk >/=30% estimated from the Joint British Societies CHD risk chart. Glycaemic control should also be optimised in diabetic subjects. Specific advice is given on the management of hypertension in specific patient groups, ie, the elderly, ethnic subgroups, diabetes mellitus, chronic renal disease and in women (pregnancy, oral contraceptive use and hormone replacement therapy). Suggestions for the implementation and audit of these guidelines in primary care are provided.

The Physical Activity for Total Health (PATH) Study: rationale and design

PURPOSE

Physical activity has been associated with a decreased risk for breast cancer. Mechanisms for this association may involve hormonal pathways. The Physical Activity for Total Health study is testing the effect of a 1-yr moderate intensity physical activity intervention on the endogenous sex hormone profile of postmenopausal women in a randomized controlled study.

METHODS

Women (N = 168) who are aged 55-75 yr, not using sex hormones, sedentary, nonsmokers, have no endocrine-related disease or cancer, and with body mass index of 25.0 or greater, are eligible. Women are recruited through mass mailings and media advertising and are randomized to either a 1-yr moderate intensity aerobic and strength training exercise program (monitored group exercise sessions plus home exercise) or a control program (stretching classes).

RESULTS

Serum hormones to be assayed at baseline and at the end of the study include: total estrone, total estradiol, free estradiol, percent bioavailable estradiol, estrone sulfate, sex hormone binding globulin, albumin, testosterone, free testosterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, insulin, glucose, and triglycerides. Other outcome measures include: the ratio of urinary 2-hydroxyestrone: 16alpha-hydroxyestrone (an estrogen metabolite ratio that may be associated with risk for breast cancer), weight, body mass index, total fat mass, and body fat distribution (waist:hip circumference ratio, DEXA scan, and abdominal fat measured by computed tomography).

CONCLUSION

This study is the first to examine the effect of change in physical activity level on sex hormones in postmenopausal women. It will provide insight into possible mechanisms through which physical activity might be associated with reduced risk of breast cancer.

Bone marrow involvement in breast cancer detected by positron emission tomography

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Exercise clinical trials in cancer prevention research: a call to action

The experimental study design can yield valuable information in measuring the association between physical activity and occurrence of cancers. Randomized clinical exercise trials can provide insight into the avenues through which physical activity might affect cancer development and can provide experience with diffusing an exercise intervention into certain populations. This report describes the potential utility of the randomized clinical trial design in providing answers about bias, mechanisms, behavior change, and dose-response in defining the causal pathway between physical activity and cancer. The challenges and limitations of exercise clinical trial are discussed. The research experience in cardiovascular disease and exercise is used as a model for developing a research agenda to explore the potential role of physical activity as a cancer-prevention modality. We recommend that a series of small clinical trials of exercise interventions be conducted to measure exercise change effects on biomarkers for cancer risk, to learn about exercise behavior change in individuals at risk for cancer, and to serve as feasibility studies for larger randomized controlled trials of cancer and precursor end points and for community intervention studies.

Treatment of mandibular angle fractures with a malleable noncompression miniplate

PURPOSE

This study evaluated the results in patients treated for fractures of the mandibular angle with a single, thin, malleable miniplate designed for use in the midface.

PATIENTS AND METHODS

Forty-six patients with 51 fractures of the mandibular angle were treated by open reduction and internal fixation using one noncompression, thin, malleable miniplate and 1.3-mm self-threading screws placed through a transoral incision. No patient was placed into postsurgical maxillomandibular fixation. They were prospectively studied for complications.

RESULTS

Seven patients (15.2%) experienced complications. All were considered minor and did not require hospitalization. Three had asymptomatic fracture of the bone plate, but at the time of diagnosis the fracture had already healed and it required no treatment. Two patients had fracture of the bone plate with continued fracture mobility requiring maxillomandibular fixation. Three minor infections occurred requiring intraoral incision and drainage.

CONCLUSIONS

The use of this small bone plate for fractures of the angle of the mandible provided adequate fixation in most cases but was associated with an unacceptable incidence of plate fracture. However, the results also indicate that the fixation requirements for angle fractures is less than previously thought.

Comparison of the Block and the Willett self-administered semiquantitative food frequency questionnaires with an interviewer-administered dietary history

The performances of two commonly used diet instruments, the Block and the Willett food frequency questionnaires, were compared with a longer, interviewer-administered diet history. Participants in a case-control study on diet and colon cancer were interviewed between 1990 and 1994 in northern California, Utah, and Minnesota by trained nutritionists using a validated diet history. Two separate subsamples of participants were asked to complete either the Block or the Willett questionnaire exactly 5 days after they completed the original diet history. Data were analyzed separately by subsample comparing either the Block or the Willett questionnaire with the original diet history by using means, correlations, quintile agreement, and odds ratios for the relation between several nutrients and colon cancer. The Block and the Willett questionnaires generally provided lower absolute intake estimates than did the original diet history; however, the Block questionnaire underestimated more than did that by Willett. Both correlations and quintile agreement were slightly better for the Willett questionnaire than for that by Block when compared with the original diet history. In general, point estimates obtained from either the Block or the Willett questionnaire fell within the confidence intervals of the estimates of the odds ratios obtained from the original diet history, and no real difference in significance levels appeared. Although the Block and Willett questionnaires differed slightly from each other and from our original diet history in estimating absolute nutrients and ranking or classifying individuals, they were very similar in their ability to predict disease outcome.

Impact of a risk-based prevention policy on neonatal group B streptococcal disease

OBJECTIVE

Neonatal group B streptococcal infections can be prevented by intrapartum antibiotic prophylaxis. Beginning in 1992, women with obstetric risk factors at University of Miami-Jackson Memorial Medical Center were targeted to receive intrapartum antibiotic prophylaxis. We evaluated these preventive efforts.

STUDY DESIGN

A case was defined as isolation of group B streptococci from a sterile site in an infant <7 days old born during the study period, 1992-1995. We reviewed systematic samples of women with preterm delivery and prolonged rupture of membranes to assess use of intrapartum antibiotic prophylaxis.

RESULTS

Group B streptococcal cases declined from 1.7 cases/1000 live births to 0.2 cases/1000 live births (Poisson regression, P =.002). Intrapartum antibiotic prophylaxis use increased from 13% of preterm deliveries in 1992 to 42% in 1995, and from 20% of deliveries with prolonged rupture of membranes in 1992 to 72% in 1995 (chi2 test for linear trend P =.007 and P <.001, respectively).

CONCLUSION

Provision of intrapartum antibiotic prophylaxis on the basis of risk factors was associated with decreased group B streptococcal disease.

The process of rehabilitation and discharge planning in stroke: a controlled comparison between stroke units

BACKGROUND AND PURPOSE

Stroke units improve outcome for stroke patients. Comparative controlled studies between stroke units are required to determine which components of stroke unit rehabilitation influence outcome and which may be investigated further in randomized controlled trials. This study compares 2 stroke units with regard to the effect differences in practice have on functional recovery (Barthel Index score) and discharge planning (length of stay).

METHODS

Stroke unit patients with moderate disability (Barthel score of 4 to 10 at week 1) admitted over 18 months were studied. Barthel measurements were obtained weekly from week 1 to discharge. Details of stroke unit function were recorded. The core features of stroke units were in place in both units. Rehabilitation was impairment focused (theoretically driven) on one unit and disability oriented (pragmatic) on the other.

RESULTS

Numbers of patients were comparable (85 versus 99). Median Barthel score at week 1 (6 versus 6), time to maximal Barthel score (14 versus 14 weeks), discharge Barthel score (14 versus 14), and institutionalization (32% versus 28%) were similar in both units. Median lengths of stay differed (68 versus 49 days; P<0.001).

CONCLUSIONS

Comparisons with regard to the rehabilitation process can be made between stroke units. Differences in rehabilitation process between 2 units showed no effect on the rate of functional recovery. Length of stay was significantly different between units, an effect that cannot be attributed to functional recovery and therefore reflects differences in discharge planning, including postdischarge support.

Physical activity and cancer etiology: associations and mechanisms

OBJECTIVES

This paper reviews the epidemiologic data of associations between physical activity and cancer risk, describes potential mechanisms for a physical activity cancer link, and proposes future directions for research.

METHODS

We reviewed English-language published papers on physical activity and cancer through Medline searches for epidemiologic studies, and through references on individual reports. We reviewed general texts on effects of exercise on human biology and applied the concepts to the biology of cancer in humans to describe potential mechanisms for a physical activity-cancer association.

RESULTS

Considerable epidemiologic evidence has accrued linking increased physical activity with reduced occurrence of cancers of the breast and colon. The association between physical activity and cancers of other sites is unclear. Potential mechanisms for the association between physical activity and reduced risk for breast and colon cancer are varied: they range from bias due to physical activity's strong correlations with other health factors (e.g., diet, smoking, alcohol use, use of medications) to the metabolic effects resulting from increased physical activity and fitness, such as reduced obesity, hormonal and reproductive effects, mechanical effects, and enhancement of the immune system.

CONCLUSIONS

The elucidation of biologic mechanisms for an association between physical activity and cancer may provide biological support for the association. It will contribute information to determine the type, frequency, and duration of exercise needed to maximize protection. This information will be needed before large-scale community interventions are begun, in order to choose the correct interventions for the desired effect of reduced incidence of the most common cancers.

Improved gene transfer into baboon marrow repopulating cells using recombinant human fibronectin fragment CH-296 in combination with interleukin-6, stem cell factor, FLT-3 ligand, and megakaryocyte growth and development factor

We have used a competitive repopulation assay in baboons to develop improved methods for hematopoietic stem cell transduction and have previously shown increased gene transfer into baboon marrow repopulating cells using a gibbon ape leukemia virus (GALV)-pseudotype retroviral vector (Kiem et al, Blood 90:4638, 1997). In this study using GALV-pseudotype vectors, we examined additional variables that have been reported to increase gene transfer into hematopoietic progenitor cells in culture for their ability to increase gene transfer into baboon hematopoietic repopulating cells. Baboon marrow was harvested after in vivo administration (priming) of stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF). CD34-enriched marrow cells were divided into two equal fractions to directly compare transduction efficiencies under different gene transfer conditions. Transduction by either incubation with retroviral vectors on CH-296-coated flasks or by cocultivation on vector-producing cells was studied in five animals; in one animal, transduction on CH-296 was compared with transduction on bovine serum albumin (BSA)-coated flasks. The highest level of gene transfer was obtained after 24 hours of prestimulation followed by 48 hours of incubation on CH-296 in vector-containing medium in the presence of multiple hematopoietic growth factors (interleukin-6, stem cell factor, FLT-3 ligand, and megakaryocyte growth and development factor). Using these conditions, up to 20% of peripheral blood and marrow cells contained vector sequences for more than 20 weeks, as determined by both polymerase chain reaction and Southern blot analysis. Gene transfer rates were higher for cells transduced on CH-296 as compared with BSA or cocultivation. In one animal, we have used a vector expressing a cell surface protein (human placental alkaline phosphatase) and have detected 10% and 5% of peripheral blood cells expressing the transduced gene 2 and 4 weeks after transplantation as measured by flow cytometry. In conclusion, the conditions described here have resulted in gene transfer rates that will allow detection of transduced cells by flow cytometry to facilitate the evaluation of gene expression. The levels of gene transfer obtained with these conditions suggest the potential for therapeutic efficacy in diseases affecting the hematopoietic system.

Routine protein energy supplementation in adults: systematic review

OBJECTIVES

To determine whether routine oral and enteral nutritional supplementation can improve the weight, anthropometry, and survival of adult patients.

DESIGN

Systematic review of randomised controlled trials of oral or enteral protein supplementation in adults. Trials were identified from Medline (Silver Platter 3.11, 1966-96), reference lists of identified studies and review articles, and communication with feed manufacturers.

SUBJECTS

Randomised controlled trials comparing oral or enteral protein supplementation with no routine supplementation. All trials of adult subjects were included except those addressing nutrition in pregnancy.

MAIN OUTCOME MEASURES

Change in body weight and anthropometry (mid-arm muscle circumference), and all cause case fatality recorded at the end of scheduled follow up. Body weight and anthropometry were analysed as the weighted mean difference and 95% confidence intervals of the percentage change in these variables. Case fatality was analysed with odds ratio and 95% confidence intervals.

RESULTS

32 eligible reports (2286 randomised patients) published between February 1979 and July 1996 were identified, of which 30 (93.8%) (2062 randomised patients) reported outcomes of interest. Case fatality data were available for 1670 (81%) patients, and continuous variable data for up to 1607 (78%) patients. The treatment group receiving routine nutritional supplementation showed consistently improved changes in body weight and anthropometry compared with controls; weighted mean difference 2.06% (95% confidence interval 1.63% to 2.49%) and 3.16% (2.43% to 3.89%) respectively. The pooled odds ratio for death in the treatment group was 0.66 (0.48 to 0.91, 2P<0.01). Apparent benefits were observed in several prespecified subgroups of patients, treatment settings, and interventions, but were not evident if trials with less robust methodology were excluded.

CONCLUSIONS

Routine oral or enteral supplementation seems to improve the nutritional indices of adult patients, but there are insufficient data in trials which meet strict methodological criteria to be certain if mortality is reduced. Benefits were not restricted to particular patient groups. Further large pragmatic randomised controlled trials of routine nutritional supplementation are justified.

Differential requirement for caspase 9 in apoptotic pathways in vivo

Mutation of Caspase 9 (Casp9) results in embryonic lethality and defective brain development associated with decreased apoptosis. Casp9-/- embryonic stem cells and embryonic fibroblasts are resistant to several apoptotic stimuli, including UV and gamma irradiation. Casp9-/- thymocytes are also resistant to dexamethasone- and gamma irradiation-induced apoptosis, but are surprisingly sensitive to apoptosis induced by UV irradiation or anti-CD95. Resistance to apoptosis is accompanied by retention of the mitochondrial membrane potential in mutant cells. In addition, cytochrome c is translocated to the cytosol of Casp9-/- ES cells upon UV stimulation, suggesting that Casp9 acts downstream of cytochrome c. Caspase processing is inhibited in Casp9-/- ES cells but not in thymocytes or splenocytes. Comparison of the requirement for Casp9 and Casp3 in different apoptotic settings indicates the existence of at least four different apoptotic pathways in mammalian cells.