Effectiveness gaps: a new concept for evaluating health service and research needs applied to complementary and alternative medicine

BACKGROUND

An effectiveness gap (EG) is an area of clinical practice in which available treatments are not fully effective. EGs have not been previously researched. Complementary and alternative medicine (CAM) interventions, by definition, are not generally available through normal health care channels. Therefore, if effective, they have the potential to increase achieved community effectiveness.

AIMS

A pilot study to determine whether EGs exist, and if so to provide initial data on their nature, frequency, and causes. To obtain preliminary data on whether CAM may offer effective interventions in these clinical areas.

DESIGN

Semistructured telephone interviews; literature search.

SETTING

Twenty-two (22) general practitioners (GPs) in London, U.K.

METHOD

One hundred and fifty-two (152) doctors who had responded to an earlier survey on attitudes to CAM were approached. Respondents were asked to specify EGs and to give reasons why available treatment is unsatisfactory and to estimate the frequency and severity of clinical problems relating to EGs. Sampling was continued to redundancy. A bibliometric study examined the volume and type of published evidence on the effectiveness of CAM interventions in the identified clinical areas.

RESULTS

There was good concordance among respondents on EGs encountered in general/family practice. Seventy-eight (78) clinical problems were cited. EGs are encountered quite frequently: 68 of 78 (85%) of EGs were encountered at least once per month. Musculoskeletal problems were cited by 20 of 22 (90%) of respondents as being affected by EGs. Depression, eczema, chronic pain, and irritable bowel syndrome were also frequently mentioned. Systematic reviews and meta-analyses conclude that there is evidence for the effectiveness of various CAM interventions in most of these areas.

CONCLUSIONS

EGs, mapped against evidence, have the potential to inform service development and research policy. Further study should be undertaken: it should incorporate improved sampling and data collection methodology. Specifically, where effective CAM interventions exist but are not being applied, EGs form part of the "avoidable burden of illness" identified by early work on evidence-based medicine. Practice guidelines should incorporate CAM interventions where there is evidence. The CAM research agenda should focus on areas affected by EGs.

Energy Substrate Metabolism of Mouse Cumulus-Oocyte Complexes: Response to Follicle-Stimulating Hormone Is Mediated by the Phosphatidylinositol 3-Kinase Pathway and Is Associated with Oocyte Maturation1

Successful in vitro maturation (IVM) of oocytes obtained from medium-sized antral follicles could avoid the need for superovulation for in vitro fertilization. The wide range of doses of FSH used in IVM prompted us to study the effect of varying concentrations of FSH on the dynamics of nutrient uptake and production by individual maturing mouse cumulus-oocyte complexes (COCs). COCs isolated from the antral follicles of unprimed, prepubertal B6CBF(1) mice were cultured individually in increasing concentrations of FSH (0-2000 ng/ml). Following culture, pyruvate, glucose, and lactate uptake or production by individual complexes were noninvasively assessed and compared with the stage of nuclear maturation of the enclosed oocyte. FSH significantly increased oocyte maturation and produced a two- to threefold increase in glucose uptake and lactate production by COCs in which the enclosed oocyte completed maturation. In these COCs, pyruvate was taken up under control conditions but was produced in progressively higher quantities in increasing concentrations of FSH. In COCs where the oocyte failed to complete maturation, pyruvate was taken up (rather than produced) and glucose uptake and lactate production were lower and unaffected by the presence or absence of FSH. This suggests that there is dialogue between cumulus cells and the maturing oocyte that influences FSH responsiveness and substrate metabolism of the whole COC. Finally, inhibition of FSH-stimulated glucose uptake by the PI3-kinase inhibitor LY294002 and the finding of GLUT4 protein in granulosa cells suggest that FSH increases glucose uptake by PI3-kinase-mediated translocation of GLUT4 to the granulosa cell membrane.

Preimplantation genetic diagnosis of spinocerebellar ataxia 3 by (CAG)n repeat detection

Spinocerebellar ataxia 3 (SCA3) is an autosomal dominant neurodegenerative disorder characterized by variable expression and a variable age of onset. SCA3/MJD (Machado-Joseph disease) is caused by an expansion of a (CAG)(n) repeat in the MJD1 gene on chromosome 14q32.1. A single cell PCR protocol has been developed for preimplantation genetic diagnosis (PGD) of SCA3 to select unaffected embryos on the basis of the CAG genotype. Single leukocytes and blastomeres served as a single cell amplification test system to determine the percentage of allelic drop-out (ADO) and PCR efficiency. Out of 105 tested heterozygous single leukocytes, 103 (98.1%) showed a positive amplification signal, while five cells (4.9%) showed ADO. Amplification in single blastomeres was obtained in 13 out of a total of 14, and ADO was observed in two out of the 13 single blastomeres. PGD of SCA3 was performed in a couple with paternal transmission of the SCA3 allele. Seven embryos were available for biopsy, all biopsied blastomeres showed amplification and no ADO occurred. One embryo was diagnosed as affected whereas six embryos were diagnosed as unaffected. Two unaffected embryos were transferred and resulted in a singleton pregnancy and the birth of a healthy girl.

Formation and early development of follicles in the polycystic ovary

BACKGROUND

Polycystic ovary syndrome is the most common cause of anovulatory infertility. It has long-term health implications and is an important risk factor for type 2 diabetes. However, little is known about the cause of polycystic ovaries. We have used detailed morphological analysis to assess the hypothesis that there is an intrinsic ovarian abnormality that affects the earliest stages of follicular development.

METHODS

We took small cortical biopsies during routine laparoscopy from 24 women with normal ovaries and regular cycles and from 32 women with polycystic ovaries, 16 of whom had regular, ovulatory cycles and 16 of whom had oligomenorrhoea. We used computerised image analysis to assess the density and developmental stage of small preantral follicles in serial sections of fixed tissue.

FINDINGS

Median density of small preantral follicles, including those at primordial and primary stages, was six-fold greater in biopsies from polycystic ovaries in anovulatory women than in normal ovaries (p=0.009). In both ovulatory and anovulatory women with polycystic ovaries, we noted a significant increase in the percentage of early growing (primary) follicles and a reciprocal decrease in the proportion of primordial follicles compared with normal ovaries.

INTERPRETATION

Our findings indicate that there are fundamental differences between polycystic and normal ovaries in early follicular development, suggesting an intrinsic ovarian abnormality. The increased density of small preantral follicles in polycystic ovaries could result from increased population of the fetal ovary by germ cells, or from decreased rate of loss of oocytes during late gestation, childhood, and puberty.

Maintenance of the inner cell mass in human blastocysts from fragmented embryos

The degree of fragmentation during early cleavage is universally used as an indicator of embryo quality during human in vitro fertilization treatment. Extensive fragmentation has been associated with reduced blastocyst formation and implantation. We examined the relationship between early fragmentation and subsequent allocation of cells to the trophectoderm and inner cell mass in the human blastocyst. We retrospectively analyzed data from 363 monospermic human embryos that exhibited varying degrees of fragmentation on Day 2. Embryos were cultured from Day 2 to Day 6 in Earle balanced salt solution with 1 mM glucose and human serum albumin. Rates of development and blastocyst formation were measured. The number of cells in the trophectoderm and inner cell mass and the incidence of apoptosis were assessed following differential labeling with polynucleotide-specific fluorochromes. Increasing fragmentation resulted in reduced blastocyst formation and lower blastocyst cell numbers. For minimal and moderate levels of fragmentation, the reduction in cell numbers was confined largely to the trophectoderm and a steady number of inner cell mass cells was maintained. However, with extensive fragmentation of more than 25%, cell numbers in both lineages were reduced in the few embryos that formed blastocysts. Apoptotic nuclei were present in both the trophectoderm and inner cell mass, with the lowest incidence in blastocysts that had developed from embryos with minor (5-10%) fragmentation. Paradoxically, higher levels of apoptosis were seen in embryos of excellent morphology, suggesting a possible role in regulation of cell number.

Gonadotrophin regimens and oocyte quality in women with polycystic ovaries

The systemic endocrine environment during the later stages of follicle development has a crucial role in co-ordinating follicular and oocyte maturation before ovulation. Polycystic ovary syndrome (PCOS) is associated with abnormal circulating hormones, abnormal peri-follicular vascularity and significant abnormalities of granulosa cell function. After induction of ovulation, fertilization rates in vivo in women with PCOS are normal, but there is an increased risk of early pregnancy loss, particularly in obese patients. After in-vitro maturation of oocytes or following ovulation induction for IVF, oocyte and embryo quality in vitro are not obviously impaired in PCOS. In some reports however, specific endocrine abnormalities, such as hyperinsulinaemia/insulin resistance, have been noted to be associated with reduced fertilization rates and abnormal early embryonic development.

Culture environment modulates maturation and metabolism of human oocytes

BACKGROUND

The clinical use of oocytes matured in vitro for IVF is increasing, but little is known about the effect of culture conditions on oocyte maturation.

METHODS

Denuded immature oocytes identified following superovulation prior to ICSI were individually matured in one of two commercial media: tissue culture medium (TCM) 199 or modified Eagle medium with Earle's modified salts (MEME). During maturation, depletion of pyruvate and accumulation of lactate in the culture medium were non-invasively measured.

RESULTS

Maturing oocytes took up pyruvate (20-30 pmol/oocyte/h) and produced lactate (2-10 pmol/oocyte/h). Oocytes matured faster in MEME, with significantly more oocytes reaching metaphase II by 24 h after oocyte retrieval compared with TCM 199 (P = 0.03). The oocytes that matured more quickly in MEME had significantly lower lactate production than oocytes that matured more slowly (P = 0.02). In TCM 199, pyruvate uptake by rapidly maturing oocytes was lower than by slowly maturing oocytes (P = 0.05). During the second incubation, from 24 to 48 h post-oocyte retrieval, pyruvate uptake in MEME was 30% lower than in TCM 199 (P = 0.007). Pyruvate uptake and lactate production differed depending on the stage of nuclear maturation: pyruvate uptake and lactate production were greater during germinal vesicle breakdown than during polar body extrusion in MEME (P < 0.05).

CONCLUSIONS

We have shown that: (i). pyruvate is a major energy source during oocyte maturation; (ii). the composition of the culture medium can affect the rate of maturation; and (iii). the culture medium and stage of nuclear maturation can affect pyruvate uptake and lactate production.

Are we ignoring potential dangers of in vitro fertilization and related treatments?

By conventional assessments, in vitro fertilization (IVF) is one of the safest medical treatments. But producing new life brings immense responsibilities. Recently, there have been disquieting reports of foetal abnormality after these treatments and here we evaluate the potential risks associated with intracytoplasmic sperm injection (ICSI), embryo freezing and pre-implantation genetic diagnosis. In our opinion, before translating new techniques into practice, more research, particularly in animals,is desirable. In addition, better child follow-up and a fresh approach to regulation are also needed.

Caspase activity and expression of cell death genes during development of human preimplantation embryos

It has been observed that apoptosis occurs in human blastocysts. In other types of cell, the characteristic morphological changes seen in apoptotic cells are executed by caspases, which are regulated by the BCL-2 family of proteins. This study investigated whether these components of the apoptotic cascade are present throughout human preimplantation development. Developing and arrested two pronucleate embryos at all stages were incubated with a fluorescently tagged caspase inhibitor that binds only to active caspases, fixed, counterstained with 4,6-diamidino-2-phenylindole (DAPI) to assess nuclear morphology and examined using confocal microscopy. Active caspases were detected only after compaction, at the morula and blastocyst stages, and were frequently associated with apoptotic nuclei. Occasional labelling was seen in arrested embryos. Expression of proapoptotic BAX and BAD and anti-apoptotic BCL-2 was examined in single embryos using RT-PCR and immunohistochemistry. BAX and BCL-2 mRNAs were expressed throughout development, whereas BAD mRNA was expressed mainly after compaction. Simultaneous expression of BAX and BCL-2 proteins within individual embryos was confirmed using immunohistochemistry. The onset of caspase activity and BAD expression after compaction correlates with the previously reported appearance of apoptotic nuclei. As in other types of cell, human embryos express common molecular components of the apoptotic cascade, although apoptosis appears to be suppressed before compaction and differentiation.

Mathematical models of the balance between apoptosis and proliferation

As our understanding of cellular behaviour grows, and we identify more and more genes involved in the control of such basic processes as cell division and programmed cell death, it becomes increasingly difficult to integrate such detailed knowledge into a meaningful whole. This is an area where mathematical modelling can complement experimental approaches, and even simple mathematical models can yield useful biological insights. This review presents examples of this in the context of understanding the combined effects of different levels of cell death and cell division in a number of biological systems including tumour growth, the homeostasis of immune memory and pre-implantation embryo development. The models we describe, although simplistic, yield insight into several phenomena that are difficult to understand using a purely experimental approach. This includes the different roles played by the apoptosis of stem cells and differentiated cells in determining whether or not a tumour can grow; the way in which a density dependent rate of apoptosis (for instance mediated by cell-cell contact or cytokine signalling) can lead to homeostasis; and the effect of stochastic fluctuations when the number of cells involved is small. We also highlight how models can maximize the amount of information that can be extracted from limited experimental data. The review concludes by summarizing the various mathematical frameworks that can be used to develop new models and the type of biological information that is required to do this.

Assessing patients' preferences for characteristics associated with homeopathic and conventional treatment of asthma: a conjoint analysis study

BACKGROUND

A study was undertaken to investigate the preferences of patients with asthma for attributes or characteristics associated with treatment for their asthma and to investigate the extent to which such preferences may differ between patient subgroups.

METHODS

The economic technique of conjoint analysis (CA) was used to investigate patients' strength of preference for several key attributes associated with services for the treatment of asthma. A CA questionnaire was administered to two groups of asthma outpatients aged 18 years or older, 150 receiving conventional treatment at Whipps Cross Hospital (WC) and 150 receiving homeopathic treatment at the Royal London Homoeopathic Hospital (RL).

RESULTS

An overall response rate of 47% (n=142) was achieved. Statistically significant attributes in influencing preferences for both the WC and RL respondents were (1) the extent to which the doctor gave sufficient time to listen to what the patient has to say, (2) the extent to which the treatment seemed to relieve symptoms, and (3) the travel costs of attending for an asthma consultation. The extent to which the doctor treated the patient as a whole person was also a statistically significant attribute for the RL respondents.

CONCLUSIONS

This study has shown that aspects associated with the process of delivery of asthma services are important to patients in addition to treatment outcomes. The homeopathic respondents expressed stronger preferences for the doctor to treat them as a whole person than the patients receiving conventional treatment. Overall, the preferences for the attributes included in the study were similar for both groups.

Future developments in assisted reproduction in humans

The advent of human in vitro fertilization (IVF) over 30 years ago has made the oocyte and preimplantation embryo uniquely accessible. This accessibility has given rise to new micromanipulation techniques, such as intracytoplasmic sperm injection for treatment of male infertility, as well as embryo biopsy for preimplantation diagnosis of both genetic disease and aneuploidy, a major cause of early embryo demise and miscarriage. In the UK, average pregnancy rates after IVF and embryo transfer are < 25%, even after transfer of several embryos. Unfortunately, a third of these pregnancies involve multiple gestations. Research is currently focusing on methods to improve IVF success rates while reducing twin and triplet pregnancies and their associated increased morbidity and mortality. One approach is to develop screening methods to identify the most viable embryos, so that transfer of fewer healthy embryos will result in a higher proportion of singleton pregnancies. Screening methods include optimizing culture conditions for prolonged culture and selection of viable blastocysts for transfer, or embryo biopsy and aneuploidy screening. Assisted reproduction is also increasingly important in other branches of medicine: survival rates for cancer sufferers are improving continually and there is now a significant need for approaches to preserve fertility after sterilizing chemo-and radiotherapy treatment. Techniques for cryopreserving male and female gametes or gonadal tissue are being developed, although systems to grow and mature these gametes are in their infancy. Finally, there are also concerns regarding the safety of these new assisted reproductive technologies.

Growth factor expression and function in the human and mouse preimplantation embryo

There is increasing evidence that even before implantation, human development is regulated by embryonically and maternally derived growth factors. Studies in other mammalian species have shown that growth factors and their receptors are expressed by the preimplantation embryo and the reproductive tract. Furthermore, a number of growth factors have been shown to affect rate of embryo development, the proportion of embryos developing to the blastocyst stage, blastocyst cell number, metabolism and apoptosis. Growth factor ligands and receptors are also expressed in human embryos and the maternal reproductive tract, and supplementation of culture medium with exogenous growth factors affects cell fate, development and metabolism of human embryos in vitro. Autocrine, paracrine and endocrine pathways that may operate within the embryo and between the embryo and the reproductive tract before implantation are proposed.

Modulation of A(beta) peptides by estrogen in mouse models

Clinical studies have shown that estrogen deprivation through menopause is a risk factor in both the initiation and progression of Alzheimer's disease (AD) and that estrogen replacement therapy may be protective. One of the major pathological features in the human AD brain is the senile plaque, a proteinaceous structure composed mainly of heterogeneous peptides collectively known as A-beta (A(beta)). In vitro studies have linked estrogen with A(beta) modulation, suggesting that one-way that estrogen depletion at menopause may exacerbate the features of AD is through A(beta) accumulation. To test this, two studies were performed on transgenic models of amyloidosis. Firstly, transgenic mice without detectable amyloid aggregates were subjected to ovariectomy and estradiol supplementation, and A(beta) levels were assessed. Secondly, the effects of estrogen modulation were assessed in mice at an age when plaques would be forming initially. Overall, A(beta) levels were higher in estrogen-deprived mice than intact mice, and this effect could be reversed through the administration of estradiol. These data suggest that, in vivo, estrogen depletion leads to the accumulation of A(beta) in the CNS, which can be reversed through replacement of estradiol. These results provide evidence that post-menopausal estrogen depletion may be linked to an increased risk of AD through A(beta) modulation.

Mathematical model of FSH-induced cAMP production in ovarian follicles

During the terminal part of their development, ovarian follicles become totally dependent on gonadotropin supply to pursue their growth and maturation. Both gonadotropins, follicle-stimulating hormone (FSH) and luteining hormone (LH), operate mainly through stimulatory G protein-coupled receptors, their signal being transduced by the activation of the enzyme adenylyl cyclase and the production of second-messenger cAMP. In this paper, we develop a mathematical model of the dynamics of the coupling between FSH receptor stimulation and cAMP synthesis. This model takes the form of a set of nonlinear, ordinary differential equations that describe the changes in the different states of FSH receptors (free, bound, phosphorylated, and internalized), coupling efficiency (activated adenylyl cyclase), and cAMP response. Classical analysis shows that, in the case of constant FSH signal input, the system converges to a unique, stable equilibrium state, whose properties are here investigated. The system also appears to be robust to nonconstant input. Particular attention is given to the influence of biologically relevant parameters on cAMP dynamics.

Bilateral phrenic paralysis in a patient with systemic lupus erythematosus

Respiratory manifestations of systemic lupus erythematosus (SLE) are frequent. They include respiratory muscle abnormalities, which have been implicated in the pathogenesis of the "shrinking lung syndrome" (SLS). We report the case of a patient with this syndrome, in whom diaphragmatic paralysis due to demyelinating phrenic lesions was diagnosed at the same time as SLE. Follow-up studies showed a favorable clinical and diaphragmatic outcome with corticosteroid therapy, but little change in spirometry. It is concluded that severe diaphragm palsy is possibly due to phrenic nerve lesions in SLE, and that the link between diaphragm dysfunction and the SLS is probably not a straightforward one.

Amino acids promote human blastocyst development in vitro

Supplementation of culture media with amino acids has been shown to benefit preimplantation embryo development in several species. This randomized study analysed the in-vitro development of human embryos obtained after IVF in the presence or absence of a combination of amino acids from the 2- to 4-cell stage to the blastocyst stage. A total of 129 human embryos was randomly distributed between three serum-free chemically defined sequential media: (i) glucose-free Earle's balanced salt solution (EBSS) with glutamine (Gln) prior to morula stage, supplemented with glucose for blastocyst formation; (ii) glucose-free EBSS with glutamine and non-essential amino acids (AA) for cleavage stage development, and supplemented with all 20 AA for blastocyst formation (Earle's+AA); and (iii) a sequential commercial medium containing amino acids (K-SCIM). Embryos were individually cultured for successive periods of 24 h. On day 6 of development, blastocysts were differentially labelled and the numbers of trophectoderm and inner cell mass cells, mitoses and dead cells were examined. Blastocyst development was similar for the three sequential media. The mixture of AA significantly increased total blastocyst cell numbers from 61.8 +/- 4.2 with Earle's+Gln to 99.3 +/- 8.4 with Earle's+AA and 100.2 +/- 9.4 with K-SCIM (P = 0.005). This increase was present in both the trophectoderm and inner cell mass lineages (P < 0.02). Furthermore, the dead cell index was significantly lower with Earle's+AA (P = 0.047).

From cell death to embryo arrest: mathematical models of human preimplantation embryo development

Human preimplantation embryos exhibit high levels of apoptotic cells and high rates of developmental arrest during the first week in vitro. The relation between the two is unclear and difficult to determine by conventional experimental approaches, partly because of limited numbers of embryos. We apply a mixture of experiment and mathematical modeling to show that observed levels of cell death can be reconciled with the high levels of embryo arrest seen in the human only if the developmental competence of embryos is already established at the zygote stage, and environmental factors merely modulate this. This suggests that research on improving in vitro fertilization success rates should move from its current concentration on optimizing culture media to focus more on the generation of a healthy zygote and on understanding the mechanisms that cause chromosomal and other abnormalities during early cleavage stages.

Stage-specific and differential expression of gap junctions in the mouse ovary: connexin-specific roles in follicular regulation

Gap junction communication plays an essential role in follicle growth. Immunocytochemistry and confocal microscopy were used to examine the expression of gap junction connexins of the alpha and beta subfamilies in follicles from primordial to preovulatory stages in the ovaries of prepubertal and adult mice. Connexin-specific antibodies detected alpha(1), alpha(4), alpha(6), beta(1), beta(2) and beta(4) connexins within follicles. In adult ovaries connexin immunolabelling was stronger in larger (more mature) follicles than it was in smaller follicles, with comparatively reduced labelling detected in prepubertal ovaries. In healthy follicles, labelling for alpha subfamily connexins was detected between granulosa cells, whereas labelling for beta subfamily connexins was found in the theca. Labelling for beta subfamily connexins and alpha(4) connexin (preantral stage) was detected on the oocyte surface membrane. In atretic follicles, labelling for beta(4) connexin appeared between the granulosa cells. These results demonstrate that alpha and beta connexin subfamilies are segregated to separate cellular compartments in the mouse follicle. The results are discussed in the light of possible roles for differential gap junctional communication in the regulation of folliculogenesis, oocyte maturation and atresia.

Anti-apoptotic action of insulin-like growth factor-I during human preimplantation embryo development

Insulin-like growth factor I (IGF-I) has been shown to increase the proportion of embryos forming blastocysts and the number of inner cell mass cells in human and other mammalian preimplantation embryos. Here we examined whether the increased cell number resulted from increased cell division or decreased cell death. Normally fertilized, Day 2 human embryos of good morphology were cultured to Day 6 in glucose-free Earle's balanced salt solution supplemented with 1 mM glutamine, with (n = 42) and without (n = 45) 1.7 nM IGF-I. Apoptotic cells in Day 6 blastocysts were identified using terminal deoxynucleotidyl dUTP terminal transferase (TUNEL) labeling to detect DNA fragmentation and 4'-6-diamidino-2-phenylindole (DAPI) counterstain to evaluate nuclear morphology. The number of nuclei and extent of DNA and nuclear fragmentation was assessed using laser scanning confocal microscopy. IGF-I significantly increased the proportion of embryos developing to the blastocyst stage from 49% (control) to 74% (+IGF-I) (P < 0.05). IGF-I also significantly decreased the mean proportion of apoptotic nuclei from 16.3 +/- 2.9% (-IGF-I) to 8.7 +/- 1.4% (+IGF-I) (P < 0.05). The total number of cells remained similar between both groups (61.7 +/- 4.6 with IGF-I; 54.5 +/- 5.1 without IGF-I). The increased number of blastocysts combined with reduced cell death suggests that IGF-I is rescuing embryos in vitro which would otherwise arrest and acting as a survival factor during preimplantation human development.

Benzo[c]quinolizin-3-ones: a novel class of potent and selective nonsteroidal inhibitors of human steroid 5alpha-reductase 1

The synthesis and biological evaluation of a series of novel, selective inhibitors of isoenzyme 1 of human 5alpha-reductase (5alphaR) (EC 1.3.99.5) are reported. The inhibitors are 4aH- (19-29) or 1H-tetrahydrobenzo[c]quinolizin-3-ones (35-47) bearing at positions 1, 4, 5, and 6 a methyl group and at position 8 a hydrogen, methyl group, or chlorine atom. All these compounds were tested toward 5alphaR-1 and 5alphaR-2 expressed in CHO cells (CHO 1827 and CHO 1829, respectively) resulting in selective inhibitors of the type 1 isoenzyme, with inhibitory potencies (IC(50)) ranging from 7.6 to 9100 nM. The inhibitors of the 4aH-series, having a double bond at position 1,2, were generally less active than the corresponding inhibitors of the 1H-series having the double bond at position 4,4a on the A ring. The presence of a methyl group at position 4 (as in compounds 39-40 and 45-47), associated with a substituent at position 8, determined the highest inhibition potency (IC(50) from 7.6 to 20 nM). Compounds 39 and 40, having K(i) values of 5.8+/-1.8 and 2.7+/-0.6 nM, respectively, toward 5alphaR-1 expressed in CHO cells, were also tested toward native 5alphaR-1 in human scalp and 5alphaR-2 in human prostate homogenates, in comparison with finasteride and the known 5alphaR-1-selective inhibitor LY191704, and their mechanism of inhibition was determined. They both inhibited the enzyme through a reversible competitive mechanism and again were selective inhibitors of 5alphaR-1 with IC(50) values of 41 nM. These specific features make these inhibitors suitable candidates for further development as drugs in the treatment of DHT-dependent disorders such as acne and androgenic alopecia in men and hirsutism in women.

Follow-up of radial arterial catheterization for positron emission tomography studies

Radial arterial catheterization is needed for repeated arterial blood samples to construct tracer input curves of positron emission tomography (PET) scans (Herscovitch [1993]: Rheum Dis Clin North Am 19:765-794). Complications resulting from such short-term catheterizations are rare. Sixteen investigators followed 106 subjects who had arterial lines placed in the context of a PET study. Abnormalities were reported in 8 of 106 (7.5%) cases. Of these eight cases, three (37.5%) were inpatients diagnosed with anorexia nervosa, a condition that may represent a risk factor. All abnormalities were benign, did not affect motor function, and did not require medical intervention.

[Thoracoscopic treatment of pulmonary hydatidosis: a case report]

Hydatidosis is a ubiquitous parasitic condition observed in a pulmonary localization in 30 to 40% of cases. The hydatid cyst develops slowly and is well tolerated by the host who presents no signs for a long period. Complications include compression, fissuration, rupture, anaphylactic shock or infection after a latency phase of variable duration. Treatment of pulmonary hydatidosis is classically surgical with enucleation of the cyst by cleavage between the adventice and the anhistic membrane via thorachotomy using the Ugon and Barret procedure. Needle aspiration is also possible via thorachotomy or thoracoscopy. Finally resection of the pulmonary parenchyma can be used to excise the hydatic cyst. We describe a thoracoscopic treatment using specific material, in a man with complications due to a voluminous pulmonary hydatid cyst.

Noninvasive assessment of glucose and pyruvate uptake by human embryos after intracytoplasmic sperm injection and during the formation of pronuclei

OBJECTIVE

To improve in vitro culture conditions and human embryo selection before transfer after IVF with intracytoplasmic sperm injection (ICSI).

DESIGN

A controlled, randomized, prospective study.

SETTING

University hospital-based IVF-ET program.

PATIENT(S)

Couples undergoing ICSI.

INTERVENTION(S)

Culture of human embryos in the presence of 1 mM or 5.56 mM glucose and metabolic measurements with the use of noninvasive microfluorescence assays immediately after ICSI to the time of transfer.

MAIN OUTCOME MEASURE(S)

Embryo development, implantation rate, and glucose and pyruvate uptake.

RESULT(S)

Fertilization rates, early embryo development, and implantation rates were not significantly different between 1 mM and 5.56 mM glucose. Pyruvate uptake was significantly higher during the formation of the pronuclei, at 15 +/- 0.7 and 11.4 +/- 1.3 pmol/embryo/h for fertilized and unfertilized oocytes, respectively. Pyruvate uptake did not correlate with cleavage stage or embryo morphology. However, during the second day of incubation, pyruvate uptake was significantly higher for the untransferred embryos of pregnant women compared with nonpregnant women, at 17.9 +/- 1.5 and 10.8 +/- 1.0 pmol/embryo/h, respectively.

CONCLUSION(S)

The increased level of pyruvate uptake during fertilization reflects the increased demand for energy necessary for the formation of the pronuclei. However, the metabolic measurements could not improve the selection of embryos with the best implantation potential. Finally, the reduction of glucose concentration in the culture medium failed to improve embryo viability.

New protocol for DNA extraction of stool

Present methods for DNA isolation of stool have various limitations such as the amount of stool used, the requirement of lavage fluids or the use of fresh stool. In this paper, a new method is described for the isolation of human nucleic acids from stool, which is independent from the moment of collection. Fecal samples as dry as possible were collected from 75 patients; two grams of stool were mixed with a lysis buffer containing phenol. DNA yields of crude stool were variable and ranged from 9-1686 micrograms/g of feces. With dot blots in 9 of the 75 cases, the human DNA was identified and ranged from 0.06%-46%. In the remaining 66 cases, human genomic DNA was detected by nested PCR, using human K-ras gene amplification as an example. Amplification products were confirmed for human K-ras with the exonuclease-amplification coupled capture technique (EXACCT). In conclusion, the developed DNA isolation method can be used for the study of large numbers of stool samples, is independent of the age or method of stool collection and is suitable for large-scale screening studies.

In vitro maturation of oocytes

Only about 400 of the one million oocytes present at birth will be ovulated, while the rest will die by atresia. The ability to rescue oocytes destined to die and mature them in vitro would provide invaluable information about folliculogenesis and oocyte maturation, and could provide oocytes for infertile women. In vitro maturation (IVM) is challenging in the human because folliculogenesis is a lengthy process encompassing many complex cellular changes in the oocyte and its surrounding follicle cells. A few live births have resulted from the maturation and fertilization of immature human oocytes aspirated from small antral follicles. Furthermore, it is possible to grow primordial follicles to pre-antral stages in slices of ovarian tissue, and support antrum formation in isolated pre-antral follicles. However, we are still a considerable way from growing and maturing pre-antral follicles to pre-ovulatory stages in vitro. The importance of the follicular environment for producing a healthy and developmentally competent oocyte is illustrated by the oocyte's susceptibility to errors during meiosis. This counsels considerable caution in the development of IVM for clinical application.

Excitotoxic cell death dependent on inhibitory receptor activation

Although excitotoxic cell death is usually considered a Ca(2+)-dependent process, in certain neuronal systems there is strong evidence that excitotoxic cell death is independent of Ca2+ and is instead remarkably dependent on extracellular Cl-. We have shown (in isolated chick embryo retina) that at least some of the lethal Cl- entry is through GABA and glycine receptors. Here we show that when all the GABA and glycine receptors are blocked by using an appropriate cocktail of inhibitors, agonist-induced excitotoxic cell death can be completely prevented. To determine if ligand-gated Cl- channels contribute to excitotoxic cell death in other neurons, we examined KA-induced cell death in cultured rat cerebellar granule cells. GABA receptor blockade with either a competitive or noncompetitive antagonist provides complete neuroprotection. KA stimulates Cl- uptake by the granule cells, and this is blocked by the GABA antagonists. Granule cell cultures take up [3H]GABA and release it in response to KA treatment. A subpopulation of neurons in the cultures is shown to have GAD and high concentrations of GABA, and this presumably is the source of the GABA that leads to receptor activation and lethal Cl- entry. Finally, we show that retinal cell death due to 1 h of simulated ischemia (combined oxygen and glucose deprivation) is completely prevented by blocking the inhibitory receptors. These results indicate that, paradoxically, excitotoxic cell death is completely dependent on activation of inhibitory receptors, in at least some neuronal systems, and this pathological process may contribute to disease.

Human primordial, primary and secondary ovarian follicles in long-term culture: effect of partial isolation

Ovarian cortical tissue, donated by 20 women aged 25-43 years during gynaecological laparoscopies or laparotomies, was first cultured for 7-9 days as tissue slices, 0.1-0.3 mm in thickness, in extracellular matrix, to initiate the growth of the primordial and primary follicles. It was then divided into two parts, one of which was cultured further as slices, and the other one used for enzymatic (collagenase at 1, 0.5 or 0.25 mg/ml; 17 patients) or mechanical (four patients) partial isolation of the follicles. The tissue slices and the partially isolated follicles were cultured for a further 1-3 weeks in the matrix. After approximately 2 weeks in culture, some oocytes began to extrude from the follicles, which were usually at the secondary stage. They were small, 20-80 micrometer in diameter, and had a thin or absent zona. Polar bodies and meiotic chromosomes could be seen in these naked oocytes. This premature extrusion probably resulted from sub-optimal culture conditions. It occurred sooner in follicles that had been partially isolated using collagenase. Histologically, larger numbers of oocytes were observed in non-isolated slice cultures than in the partially isolated cultures. Initiation of growth of the follicles occurred during the first 7-9 days in culture within slices. In non-isolated slices and following mechanical partial isolation there were significantly more secondary follicles after 11-18 days in culture than following isolation with collagenase. The proportion of atretic follicles increased during all cultures, and it was significantly higher after partial isolation. Because partial isolation did not improve the survival or development of the follicles the optimal method for human ovarian follicles could be to culture them non-isolated within small tissue slices.

Effects of taurine on human embryo development in vitro

Glutamine and taurine are reported to be beneficial for mouse embryo development in vitro, and we have recently shown that glutamine improves human blastocyst formation in vitro. This randomized study compared the development of supernumerary human embryos in the presence of 1 mmol/l glutamine and/or 5 mmol/l taurine from the 2-4-cell stage to the blastocyst stage. Blastocyst development and cell numbers were similar in the presence of glutamine or taurine: 52.6% and 58.3% of the embryos reached the blastocyst stage, respectively. Pyruvate uptake was similar in the presence of glutamine or taurine throughout development, as was lactate production after the 8-cell stage. Before this stage, lactate production was 4-fold higher in the presence of taurine (P < 0.001). The proportion of embryos reaching the blastocyst stage was similar with glutamine alone or with glutamine and taurine (62.5% and 47.2% respectively), as were the blastocyst cell numbers (63.0 +/- 4.6 and 61.0 +/- 5.1 respectively). In conclusion, taurine supports development of 2-4-cell human embryos to the blastocyst stage, although it does not further augment the beneficial effects of glutamine.

Apoptosis in the human embryo

Preimplantation human embryos are characterized by various degrees of cytoplasmic fragmentation, and a high incidence of developmental arrest before the blastocyst stage. This review examines the current morphological and biochemical evidence that apoptosis plays a role in early human development and embryonic loss. Embryos examined 24 h or more after arrest often show characteristic features of apoptosis including cytoplasmic, nuclear and DNA fragmentation. In contrast, embryos of good morphology that appear to be developing normally show no evidence of apoptosis before compaction. However, at the morula and blastocyst stages, scattered cells with fragmented nuclei and DNA characteristic of cells undergoing apoptosis are common features. Apoptosis may result from suboptimal culture conditions, or may be involved in the elimination of abnormal cells. However, the causes, role and regulation of apoptosis in the human preimplantation embryo remain to be determined.

Regional distribution in the mouse of proteins homologous to artery-specific antigenic proteins (ASAPs)

We have reported the sequences of four novel proteins derived from extracts of human aortic tissue and a cDNA library from human aortic adventitia. These proteins are immunoreactive with serum immunoglobulins from patients with abdominal aortic aneurysms (AAA), and they have homologies of amino acid sequence with microfibrillar proteins of connective tissue. We are reporting separately that two of these proteins are artery-specific antigenic proteins (ASAPs) in man. The present work investigates the regional distribution of these two proteins (AAAP-40 and MatCAM-1) in mouse (E-beta-b). Antibodies were raised in rabbit against polypeptides encoding novel amino acid sequences, unique to these proteins (e.g., not reported in GenBank). Immunohistochemical studies with these two specific antibodies show conspicuous immunoreactivity of collagen-associated microfibrils in the aortic adventitia of the murine abdominal and thoracic aorta. Immunoreactive peptides were not present in brain, muscle, or kidney. These findings support the hypothesis that proteins occur in the mouse that are homologous to a unique family of aortic microfibrillar proteins in man.

Effects of follicle-stimulating hormone and serum substitution on the in-vitro growth of human ovarian follicles

In-vitro maturation (IVM) of human ovarian follicles and oocytes could benefit infertile women, and allow the development of in-vitro systems for the study of human follicular development. Little is known about the initiation of growth of primordial follicles and the regulation of early folliculogenesis. An ovarian tissue-slice culture system was used to examine the effects of media composition, follicle stimulating hormone (FSH) and serum substitution on the development of small human follicles in vitro. Human ovarian cortex biopsies were cut into small pieces and cultured for 5, 10 or 15 days. Control (non-cultured) and cultured tissue was fixed, serially sectioned, and stained. The follicles contained within the tissue pieces were counted, measured, and assessed for stage of development and viability. Comparison of the ability of alpha-minimum essential medium (alpha-MEM), Waymouth's, or Earle's balanced salt solution (EBSS) culture media (all with 10% human serum) to support follicle growth demonstrated significantly increased initiation and growth of follicles in alpha-MEM during the first 10 days of culture. The supplementation of alpha-MEM with 300 mIU/ml FSH significantly reduced levels of atresia and increased the mean diameter of healthy follicles. Follicles in tissue cultured for 10 days with human serum albumin and ITS (insulin/transferrin/selenium mix) were significantly larger, more developed and showed significantly less atresia than those cultured with serum alone. Primordial to small preantral follicles can be grown under serum-substituted conditions in tissue-slice culture, and are responsive to FSH, which is thought to be acting mainly as a survival factor at these early stages.