Sterilisation of intellectually disabled women

Objective

To point out the proportion of intellectually disabled women (IDW) who are sterilised, and the medical and social factors associated with an increased probability to be sterilised.

Study design

A population-based study among 97% of IDW aged 18–46, attending government-accredited institutions in the region of Brussels-Capital and the province of Walloon Brabant (Belgium).

Results

Among the IDW included in this study, 22.2% are sterilised, which is superior to the 7% in the general Belgian population. Factors associated with an increased probability to be sterilised are: living in an institution, having a higher intellectual quotient (IQ), being enrolled in an institution where sexual intercourse is authorised and attending an institution where contraception is required. The last three factors are significant only among women living in institutions and the last two, only in women with severe disability. Among IDW using contraception, no factor was associated with a greater probability to be sterilised.

Conclusion

The prevalence of sterilisation among IDW is three times higher than that in the Belgian population and it is mainly correlated with factors related to the institution where these women live, especially the severely disabled.

Perforated Duodenal Ulcer and Cigarette Smoking

Whilst the association between smoking and peptic ulceration has been reported previously, the relationship between smoking and the complications of ulcers, such as perforation, bleeding or acute painful exacerbation, has not been examined. In a retrospective study comparing 275 emergency admissions for peptic ulcer with 275 controls, cigarette smoking was significantly more common only in those with a perforated duodenal ulcer. Of 128 patients with perforated duodenal ulcers, 110 (86%) were cigarette smokers compared with 65 (51%) of the 128 matched controls (χ2, P<0.01). Cigarette smoking in patients with bleeding or acutely exacerbated ulcers was not significantly more common than in controls. These findings strongly suggest a particular association between smoking and perforated duodenal ulcer.

High-dose interleukin2 - a 10-year single-site experience in the treatment of metastatic renal cell carcinoma: careful selection of patients gives an excellent outcome

Background

VEGF-targeted therapy has become the mainstay of treatment for majority of mRCC patients. For most patients, benefit is short-lived and therefore treatment remains palliative in intent. HD IL2 is an effective immunotherapy treatment capable of durable remission in some patients but its unselected use has been difficult due to its modest response rate and considerable adverse effects. Using set pathology criteria as a selection tool in clinical practice, we have been able to show improved outcomes in our previous report. Here, we present an updated and extended report of this treatment and seek to explore any pathological, clinical and treatment variables likely to predict better outcomes.

Methods

This is an extension of a previously reported clinical audit, which includes mRCC cases treated with HD IL2 between 2003 and 2013. Since 2006, tumour specimens of potential candidates were routinely reviewed prospectively and stratified into Favourable or Other categories based on constitution of histological growth pattern, namely alveolar or solid versus papillary and/or sarcomatoid architecture; clear cell versus granular cell cytoplasmic morphology. HD IL2 was preferentially offered to patients with Favourable pathology. Outcome evaluation includes response rates, survival, and treatment tolerance. Multivariate analysis was performed to explore potential prognostic and predictive factors.

Results

Among prospectively selected patients with Favourable pathology (n = 106), overall response rate was 48.1 % (51/106) with CR rate of 21.6 % (23/106). Median OS was 58.1 months. Factors associated with significantly better response and/or survival includes favourable pathology pattern, higher cycle 1 tolerance and lower number of metastatic organ sites (<3). CAIX (Carbonic anhydrase 9) has prognostic value but is not predictive of response. Toxicities were those expected of IL2 but were manageable on general medical wards, with no treatment-related death. Importantly most complete responses were durable with 76 % (23/30) cases remained relapse-free (median 39 months follow up) and 2 of the seven who relapsed had had long-term disease free survival after resection of oligometastatic relapse.

Conclusions

Our experience shows that HD IL2 remains an effective and safe treatment in well-selected cases of mRCC. The result in this single-institution patient series confirms similar outcomes to our previously reported retrospective series. Given the prospect of long-term remission, fit patients with Favourable histology and low disease burden should be considered for HD IL2 in an experienced centre. Better understanding has been gained from this in-depth analysis especially the examination of possible response predictors and strategies that can improve treatment outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-016-0174-5) contains supplementary material, which is available to authorized users.

Interventions that cause weight loss and the impact on cardiovascular risk factors: a systematic review and meta-analysis

Overweight and obesity increase the risks of diabetes and cardiovascular disease (CVD). This has been shown to be reversed with weight loss. A systematic review and meta-analysis were performed to determine the effect of weight loss in the primary prevention of CVD. PubMed, Embase and the Cochrane Library databases were searched electronically through to May 2013. Randomized controlled trials assessing weight loss and cardiovascular risk factors and outcomes were included. A random effects meta-analysis, with sub-group analyses for degree of weight loss, and age were performed. Because few studies reported clinical outcomes of CVD, analyses were limited to cardiovascular risk factors (83 studies). Interventions that caused any weight loss significantly reduced systolic blood pressure (-2.68 mmHg, 95% CI -3.37, -2.11), diastolic blood pressure (-1.34 mmHg, 95% CI -1.71, -0.97), low-density lipoprotein cholesterol (-0.20 mmol L(-1) , 95% CI -0.29, -0.10), triglycerides (-0.13 mmol L(-1) , 95% CI -0.22, -0.03), fasting plasma glucose (-0.32 mmol L(-1) , 95% CI -0.43, -0.22) and haemoglobin A1c(-0.40%, 95% CI -0.52, -0.28) over 6-12 months. Significant changes remained after 2 years for several risk factors. Similar results were seen in sub-group analyses. Interventions that cause weight loss are effective at improving cardiovascular risk factors at least for 2 years. © 2016 World Obesity.

Facial trauma

Facial trauma. Patients with facial trauma must be assessed in a systematic way so as to avoid missing any injury. Severe and disfiguring facial injuries can be distracting. However, clinicians must first focus on the basics of trauma care, following the Advanced Trauma Life Support (ATLS) system of care. Maxillofacial trauma occurs in a significant number of severely injured patients. Life- and sight-threatening injuries must be excluded during the primary and secondary surveys. Special attention must be paid to sight-threatening injuries in stabilized patients through early referral to an appropriate specialist or the early initiation of emergency care treatment. The gold standard for the radiographic evaluation of facial injuries is computed tomography (CT) imaging. Nasal fractures are the most frequent isolated facial fractures. Isolated nasal fractures are principally diagnosed through history and clinical examination. Closed reduction is the most frequently performed treatment for isolated nasal fractures, with a fractured nasal septum as a predictor of failure. Ear, nose and throat surgeons, maxillofacial surgeons and ophthalmologists must all develop an adequate treatment plan for patients with complex maxillofacial trauma.

Complex intubation, cricothyrotomy and tracheotomy

Complex intubation, cricothyrotomy and tracheotomy. Successful management of a difficult airway begins with recognizing the potential problem. When the patient cannot breathe spontaneously, oxygenation and ventilation should start first with bag-valve ventilation, with or without an airway adjunct such as a Mayo cannula, followed by an orotrache4l intubation attempt, performed by an experienced emergency doctor. If orotracheal intubation fails, a quick decision must be made regarding surgical options. In a "cannot intubate, cannot ventilate" situation, a surgical cricothyrotomy should be considered. When orotracheal intubation is impossible, but bag-valve or laryngeal mask ventilation is possible, an urgent surgical tracheostomy should be performed. In the long run, patients in need of longterm artificial ventilation will need a percutaneous or open tracheostomy. This review provides an update of all aspects of immediate and long-term airway management.

Face and neck: airway and sensorial capacities

Face and neck: airway and sensorial capacities. For the assessment and the management of face and neck trauma knowledge of the neuro-anatomy and physiology of the ear, nose, throat (ENT) and head and neck (HN) region and structures is essential, as this area is particularly vulnerable to injury. Indeed, the complex anatomy and physiology in this specific area supports important basic functions. In addition, this review elaborates on upper airway and sensorial capacities. Upper airway dimensions are influenced by bony and soft tissues. Age is of fundamental importance in the upper airway assessment, as significant differences in size and proportions apply in children and adults. The cranial nerves (CN) supply motor, sensory ad special sensory fibres to the upper airway. Injury of the CN is a frequent complication of trauma.

Obesity and the Metabolic Syndrome: The Stress on Society

The problem of obesity was only accepted by the World Health Organization as of major public health importance in 1997 when the criteria for the specification of the metabolic syndrome were also being sought. Then the risk factor analyses of the determinants of global ill health at the start of the millennium showed that an excessive body mass index (BMI) above the optimum of 21 was one of the top 10 contributors. No analyses could be related to abdominal obesity because of the absence of systematic representative surveys of waist circumferences but the ill health attributable to excess weight included the risk factors specified in the metabolic syndrome and showed that the co-morbidities in Asia were far greater than those predicted from simply an excess weight. The recent proposed definition of the metabolic syndrome includes these different criteria specified on an ethnic basis but there is now a need to recognize that abdominal obesity is more common on the developing world and linked to childhood stunting and early deprivation. The importance of intrauterine and postnatal epigenetic and altered organ function needs to be recognized. Thus the co-morbidities associated with weight gain and the development of the metabolic syndrome dominate in the developing world where the majority of the population is proving more susceptible to the effects of weight gain than Caucasians now living in affluent societies. This therefore presents a major challenge in both research and public policy terms.

FGF Ligand Family mRNA Expression Profile for Mouse Preimplantation Embryos, Early Gestation Human Placenta, and Mouse Trophoblast Stem Cells

Signaling by fibroblast growth factor (FGF) is essential is for trophoblast stem (TS) cells and preimplantation embryos. FGF4 provides essential signaling, but the expression of the complete set of 23 FGF family members has not been analyzed. Here, semi-quantitative RT-PCR and microarray analyses were used to define expression of all FGF ligand mRNA. RT-PCR was done for developmentally important FGF subfamilies, FGF10/FGF22 and FGF8/FGF17/FGF18 as well as FGF11. FGF4 and FGF18 are detected at highest levels by RT-PCR and microarrays. FGF10 was detected at low levels in both assays. FGF11 was detected at moderate levels by microarray, but not by RT-PCR. FGF17 was detected at low levels by array and moderate levels by RT-PCR. FGF8 and FGF22 were detected by RT-PCR, but not by microarrays during late cleavage divisions. FGF8, FGF5, and FGF9 were detected in the oocyte by microarray. FGF2, FGF3, and FGF7 were not detected by RT-PCR or microarrays and FGF13, FGF14, and FGF23 were not detected by microarray. Since a major role of FGF is to maintain TS cells, we tested human and mouse placental cell lines and early gestation human placenta for expression of FGF ligands. Expression in mouse TS cells was compared with preimplantation embryos, and human placental cell line expression was compared with human placenta, to infer which ligands are expressed in placental lineage vs. other cell lineages. The data suggest that human and mouse placenta share FGF18 and its high expression suggests preimplantation and early placental function.

Effects of ACh and adenosine mediated by Kir3.1 and Kir3.4 on ferret ventricular cells

The inotropic effects of ACh and adenosine on ferret ventricular cells were investigated with the action potential-clamp technique. Under current clamp, both agonists resulted in action potential shortening and a decrease in contraction. Under action potential clamp, both agonists failed to decrease contraction substantially. In the absence of agonist, application of the short action potential waveform (recorded previously in the presence of agonist) also resulted in a decrease in contraction. Under action potential clamp, application of ACh resulted in a Ba(2+)-sensitive outward current with the characteristics of muscarinic K+ current (I(K,ACh)); the presence of the muscarinic K+ channel was confirmed by PCR and immunocytochemistry. In the absence of agonist, on application of the short ACh action potential waveform, the decrease in contraction was accompanied by loss of the inward Na(+)/Ca(2+) exchange current (I(NaCa)). ACh also inhibited the background inward K+ current (I(K,1)). It is concluded that ACh activates I(K,ACh), inhibits I(K,1), and indirectly inhibits I(NaCa); this results in action potential shortening, decrease in contraction, and, as a result of the inhibition of I(K,1), minimum decrease in excitability.

Contraception of women with intellectual disability: prevalence and determinants

The contraception of women with intellectual disability (ID) is a major concern for caregivers. However, the prevalence of contraception and the frequency of use of different methods (e.g. sterilization) remain generally unknown. Moreover, indications specific to women with ID are controversial. The present authors conducted a population-based study among 97% of the women with ID aged between 18 and 46 years attending government-funded facilities in Brussels and the nearby province of Walloon Brabant in Belgium. Out of 397 subjects, 40.8% did not use any contraceptive method, 22.2% were sterilized, 18.4% used an oral contraceptive agent, 17.6% used depotmedroxyprogesterone acetate and 1% used an intrauterine device. These figures differ widely from those of the general Belgian population. Binary logistic regression for 'contraceptive utilization' showed the strong influence of institutional factors such as sleeping environment (i.e. institutional or parental), sexual relationship policy and contraception policy. Having or having had a boyfriend is also correlated with a stronger probability of contraceptive use. Other factors have a smaller influence (e.g. a milder level of ID). Very few factors, none of which are medical, are correlated with an increased use of a specific method. The present results are discussed in the light of the general medical application of contraception and the commonly assumed specific indications for women with ID.

The worldwide obesity epidemic

The recent World Health Organization (WHO) agreement on the standardized classification of overweight and obese, based on body mass index (BMI), allows a comparable analysis of prevalence rates worldwide for the first time. In Asia, however, there is a demand for a more limited range for normal BMIs (i.e., 18.5 to 22.9 kg/m(2) rather than 18.5 to 24.9 kg/m(2)) because of the high prevalence of comorbidities, particularly diabetes and hypertension. In children, the International Obesity Task-Force age-, sex-, and BMI-specific cutoff points are increasingly being used. We are currently evaluating BMI data globally as part of a new millennium analysis of the Global Burden of Disease. WHO is analyzing data in terms of 20 or more principal risk factors contributing to the primary causes of disability and lost lives in the 191 countries within the WHO. The prevalence rates for overweight and obese people are different in each region, with the Middle East, Central and Eastern Europe, and North America having higher prevalence rates. In most countries, women show a greater BMI distribution with higher obesity rates than do men. Obesity is usually now associated with poverty, even in developing countries. Relatively new data suggest that abdominal obesity in adults, with its associated enhanced morbidity, occurs particularly in those who had lower birth weights and early childhood stunting. Waist measurements in nationally representative studies are scarce but will now be needed to estimate the full impact of the worldwide obesity epidemic.

Isolation of vascular smooth muscle cells from a single murine aorta

The vascular smooth muscle cell plays a significant role in many important cardiovascular disorders, and smooth muscle biology is therefore important to cardiovascular research. The mouse is critical to basic cardiovascular research, largely because techniques for genetic manipulation are more fully developed in the mouse than in any other mammalian species. We describe here a technique for isolating smooth muscle cells from a single mouse aorta. This technique is particularly useful when material is limiting, as is frequently the case when genetically modified animals are being characterized.

Residues and mechanisms for slow activation and Ba2+ block of the cardiac muscarinic K+ channel, Kir3.1/Kir3.4

Mechanisms and residues responsible for slow activation and Ba(2+) block of the cardiac muscarinic K(+) channel, Kir3.1/Kir3.4, were investigated using site-directed mutagenesis. Mutagenesis of negatively charged residues located throughout the pore of the channel (in H5, M2, and proximal C terminus) reduced or abolished slow activation. The strongest effects resulted from mutagenesis of residues in H5 close to the selectivity filter; mutagenesis of residues in M2 and proximal C terminus equivalent to those identified as important determinants of the activation kinetics of Kir2.1 was less effective. In giant patches, slow activation was present in cell-attached patches, lost on excision of the patch, and restored on perfusion with polyamine. Mutagenesis of residues in H5 and M2 close to the selectivity filter also decreased Ba(2+) block of the channel. A critical residue for Ba(2+) block was identified in Kir3.4. Mutagenesis of the equivalent residue in Kir3.1 failed to have as pronounced an effect on Ba(2+) block, suggesting an asymmetry of the channel pore. It is concluded that slow activation is principally the result of unbinding of polyamines from negatively charged residues close to the selectivity filter of the channel and not an intrinsic gating mechanism. Ba(2+) block involves an interaction with the same residues.

Cs+ block of the cardiac muscarinic K+ channel, GIRK1/GIRK4, is not dependent on the aspartate residue at position 173

Cs+ block of GIRK1/GIRK4 expressed in Xenopus oocytes has been investigated. It has been reported that a negatively charged aspartate residue at position 172 in IRK1 is responsible for Cs+ block of the channel. IRK1, a homotetramer, has four aspartate residues at this position. GIRK1/GIRK4 is a heterotetramer and has two aspartate residues at the equivalent position (GIRK1-D173) and, consequently, it should be less sensitive to Cs+. Cs+ caused voltage-dependent block of GIRK1/GIRK4 current (measured with the two-microelectrode voltage-clamp technique). The apparent fraction of the electrical field through which Cs+ moves in order to reach its site of block (delta approximately equals 1.66) is comparable to that in IRK1, suggesting that Cs+ binds to a similar site in the two channels. GIRK1/GIRK4 was less sensitive than IRK1 to Cs+ -the Kd was 3.0-8.5 times greater and at potentials more negative than approximately or = to 130 mV there was voltage-dependent relief of block of GIRK1/GIRK4 (not the case with IRK1). However, the mutations GIRK1-D173A and GIRK1-D173Q increased the sensitivity of the channel to Cs+, while adding a negatively charged aspartate residue to GIRK4 at the equivalent position (GIRK4-N 79D) decreased Cs+ sensitivity. GIRK1-D173 cannot be the site of Cs+ block of GIRK1/GIRK4.

Inhibition of the K+ channel kv1.4 by acidosis: protonation of an extracellular histidine slows the recovery from N-type inactivation

1. Acidosis alters the transient outward current, ito, in the heart. We have studied the mechanism underlying the effect of acidosis on one of the K+ channels, Kv1.4 (heterologously expressed in Xenopus laevis oocytes), known to underlie ito. 2. At pH 6.5, wild-type Kv1.4 current was inhibited during repetitive pulsing, in part as a result of a slowing of recovery from N-type inactivation. 3. Acidosis still caused slowing of recovery after deletion of just one (either the first or second) of the N-terminal inactivation ball domains. However, deletion of both the N-terminal inactivation ball domains greatly reduced the inhibition. 4. As well as the N-terminus, other parts of the channel are also required for the effect of acidosis, because, whereas the transfer of the N-terminus of Kv1.4 to Kv1.2 conferred N-type inactivation, it did not confer acidosis sensitivity. 5. Replacement of an extracellular histidine with a glutamine residue (H508Q) abolished the slowing of recovery by acidosis. Reduction of C-type inactivation by raising the bathing K+ concentration or by the mutation K532Y also abolished the slowing. 6. It is concluded that binding of protons to H508 enhances C-type inactivation and this causes a slowing of recovery from N-type inactivation and, thus, an inhibition of current during repetitive pulsing.

Molecular and fetal tissue biopsy capabilities are needed to maximize prenatal diagnosis of junctional epidermolysis bullosa: fetal skin biopsy using a 1-mm microendoscope

OBJECTIVE

To describe a minimally invasive micro-endoscopic technique for fetal skin biopsy and direct examination for a lethal skin condition.

MATERIALS AND METHODS

Direct fetoscopic examination of a fetus was undertaken along with full thickness skin biopsies at 19 weeks' gestation.

RESULTS

No phenotypic expressions of the lethal condition were visualized and six full thickness skin biopsies were collected. Pathological examination revealed normal skin structures not consistent with junctional epidermolysis bullosa (JEB).

CONCLUSION

Minimally invasive examination with the 1 mm endoscope allows direct fetal phenotypic evaluation, full thickness skin biopsies, with risks similar to amniocentesis.

Effect of extracellular cations on the inward rectifying K+ channels Kir2.1 and Kir3.1/Kir3.4

The effects of Ba2+, Mg2+, Ca2+ and Na+ as blocking ions were investigated in 90 and 10 mM extracellular K+ solutions on the cloned inward rectifying K+ channel Kir2.1 expressed in Xenopus oocytes. Some data were also obtained using another inward rectifying K+ channel Kir3.1/Kir3.4. The addition of Ba2+ caused a concentration-, voltage- and time-dependent block of both channels. Decreasing the extracellular K+ concentration augmented the block. The data suggest that Ba2+ blocks the channels by binding to a site within the channel pore and that the electrical binding distance, delta, of the site is significantly different for Kir2.1 and Kir3. 1/Kir3.4 (0.38 and 0.22, respectively). Mg2+ and Ca2+ caused an instantaneous concentration- and voltage-dependent block of both channels. With Kir2.1, decreasing the K+ concentration augmented the block. The voltage dependence of the block was less than that of Ba2+ ([delta], 0.1), indicating a more superficial binding site for these ions within the channel pore. The affinity of the channels for Mg2+ and Ca2+ was 1000-fold lower than that for Ba2+. Addition of Na+ resulted in a concentration-, voltage- and time-dependent block of Kir2.1, similar to that observed with Ba2+. The competition between the blocking cations (for Kir2.1: Ba2+, Mg2+, Ca2+; for Kir3. 1/Kir3.4: Ba2+) and extracellular K+ suggests that the binding sites for the blocking cations may be sites to which K+ binds as part of the normal passage of K+ through the channels. It is possible that under normal physiological conditions naturally occurring extracellular cations may partly block the two inward rectifying K+ channels.

Lysyl oxidase transcripts in peritoneal adhesions and incisional scars

OBJECTIVE

To evaluate the role of lysyl oxidase in postsurgical adhesion formation and incision wound repair.

STUDY DESIGN

Female New Zealand rabbits underwent a pelvic-peritoneum adhesion-inducing operation under sterile conditions. In brief, the uterine horns were removed from the abdomen and abraded with surgical gauze and a scalpel blade. The horns were then replaced into the abdominal cavity, the incision was sutured, and the animals were allowed to recover. The animals were killed before lesion development and after 2, 4, 8, and 14 days of postsurgical recovery. The abraded uterine horns, abdominal wall incisional wound and a portion of the sidewall peritoneum were then removed. Total RNA was extracted using the guanidinium thiocyanate-phenol-chloroform method. Northern blot analysis was performed with an [alpha-32P]-labeled lysyl oxidase probe.

RESULTS

Lysyl oxidase was expressed during abdominal wall incision repair on days 2 and 4 of postsurgical recovery, declining thereafter (days 8 and 14). In contrast, no increase in lysyl oxidase expression was noted in the uterine horns as compared to the control sidewall peritoneum.

CONCLUSION

Lysyl oxidase plays a differential role in the early stages of abdominal wall and uterine horn repair.

Lithium dilution cardiac output measurement: a comparison with thermodilution

OBJECTIVE

To compare the results of cardiac output measurements obtained by lithium dilution and thermodilution.

DESIGN

Case series, observational study.

SETTING

High-dependency postoperative unit and intensive care unit of a teaching hospital.

PATIENTS

Forty patients were studied. Thirty-four patients had undergoing heart surgery requiring cardiopulmonary bypass within the previous 2 days; the diagnoses in the other patients were myocardial infarct (n = 2), septicemia (n = 2), adult respiratory distress syndrome, and pericardectomy.

INTERVENTIONS

Cardiac output was measured five times in each patient, using lithium dilution (single measurement) and bolus thermodilution (series of three to six measurements according to standard clinical practice, taking the average of the closest three). In a subgroup of 14 patients, cardiac output was also measured using "continuous thermodilution."

MEASUREMENTS AND MAIN RESULTS

Comparing lithium dilution with bolus thermodilution, the mean of the differences (lithium dilution-thermodilution) was -0.25 +/- 0.46 [SD] L/min. Linear regression analysis gave y = 0.31 + 0.89x (r2 = .94) for lithium dilution vs. thermodilution.

CONCLUSIONS

The overall agreement between the two methods was good. The variability of the thermodilution measurements was greater than that of the lithium dilution measurements. The lithium dilution method is at least as accurate as bolus thermodilution and, since pulmonary artery catheterization is not needed, it has the advantages of being safe and quick to perform.

Microcell mediated chromosome transfer maps the Fanconi anaemia group D gene to chromosome 3p

Fanconi anaemia (FA) is an autosomal recessive disorder characterized by progressive pancytopenia, short stature, radial ray defects, skin hyperpigmentation and a predisposition to cancer. Cells from FA patients are hypersensitive to cell killing and chromosome breakage induced by DNA cross-linking agents such as mitomycin C (MMC) and diepoxybutane (DEB). Consequently, the defect in FA is thought to be in DNA crosslink repair. Additional cellular phenotypes of FA include oxygen sensitivity, poor cell growth and a G2 cell cycle delay. At least 5 complementation groups for Fanconi anaemia exist, termed A through E. One of the five FA genes, FA(C), has been identified by cDNA complementation, but no other FA genes have been mapped or cloned until now. The strategy of cDNA complementation, which was successful for identifying the FA(C) gene has not yet been successful for cloning additional FA genes. The alternative approach of linkage analysis, followed by positional cloning, is hindered in FA by genetic heterogeneity and the lack of a simple assay for determining complementation groups. In contrast to genetic linkage studies, microcell mediated chromosome transfer utilizes functional complementation to identify the disease bearing chromosome. Here we report the successful use of this technique to map the gene for the rare FA complementation group D (FA(D)).

Use of site-directed antibodies to probe the topography of the alpha 2 subunit of voltage-gated Ca2+ channels

Polyclonal antibodies were raised against peptides corresponding to residues 1-15, 469-483 and 933-951 of the rabbit skeletal muscle L-type calcium channel alpha 2/delta primary translation product, for use as topological probes. Immunocytochemical comparison of the abilities of the antibodies to bind to the alpha 2 and delta subunits in intact and detergent-permeabilised rat dorsal root ganglion cells enabled the membrane orientation of these regions to be established. The resultant data indicate that the regions containing residues 1-15 and 469-483 of the alpha 2 subunit, and residues 1-17 of the delta subunit, are exposed on the extracellular surface of the membrane, findings consistent with a model that proposes alpha 2 to be entirely extracellular.

High-resolution genomic mapping of the three human replication protein A genes (RPA1, RPA2, and RPA3)

Human replication protein A (RPA) is a three-subunit protein that plays a central role in eukaryotic DNA replication, homologous recombination, and excision repair. We have previously reported the cloning and bacterial overexpression of the three RPA genes and have mapped them to chromosome 1 (RPA2), chromosome 7 (RPA3), and chromosome 17 (RPA1). We have now obtained yeast strains with artificial chromosomes carrying the three human RPA genes and report the more detailed genomic mapping of RPA. RPA1 was mapped to chromosome 17p13.3 using a combination of PCR amplification of somatic cell hybrids and radiation hybrids containing chromosome 17 fragments. RPA2 was mapped to chromosome 1p35 by PCR amplification of somatic cell hybrids of chromosome 1 and by fluorescence in situ hybridization. RPA3 was mapped to chromosome 7p22 by Southern analysis and PCR amplification of somatic cell hybrids of chromosome 7 as well as fluorescence in situ hybridization. Since RPA is an essential component of major metabolic events affecting DNA, the physical mapping of the genes for it may help elucidate the biochemical basis of genetic disorders involving DNA metabolism.

Effect of lesion size on the metabolic activity of tibial dyschondroplastic chondrocytes

Experiments were conducted to determine the influence of lesion size and method of producing tibial dyschondroplasia on metabolic activity of cultured chondrocytes. Genetic selection was one method used to produce a high incidence of tibial dyschondroplasia. Chondrocytes obtained from severe lesions exhibited reduced mitogenic activity (3H-thymidine incorporation) and ability to synthesize matrix proteoglycans (35SO4 incorporation) when compared with normal growth plate and smaller lesions. When a commercial broiler strain was used, all chondrocytes isolated from lesions induced by feeding thiram had reduced metabolic activity. Similar results were observed with severe lesions obtained from copper-deficient chicks. It is concluded that lesion size is an important factor in determining subsequent metabolic activity of chondrocytes isolated from tibial dyschondroplastic lesions.

Fibrinolytic parameters in women undergoing ovulation induction

OBJECTIVE

The purpose of this study was to evaluate the effect of elevated levels of circulating estradiol on the clotting and fibrinolytic system in patients undergoing controlled ovarian hyperstimulation.

STUDY DESIGN

Fifty-two patients undergoing controlled ovarian hyperstimulation with human menopausal gonadotropins or urofollotropin were asked to participate. Blood for hemostasis parameters was obtained on the days that patients returned for estradiol sampling. Sample days were identified as cycle days 1 to 5 (baseline), 6 to 9, and 10 to 14. Each factor was analyzed by repeated-measures analysis of variance and correlation analysis.

RESULTS

A significant decline was observed for tissue plasminogen activator antigen and plasminogen activator inhibitor type 1 activity from baseline to cycle days 10 to 14. As serum estradiol levels increased throughout each phase (maximum mean estradiol 739.8 pg/ml), a significant linear decrease was observed for both tissue plasminogen activator antigen and plasminogen activator inhibitor type 1 activity, whereas thrombin-antithrombin III complexes did not change significantly. A significant positive correlation was also observed for plasminogen activator inhibitor activity and tissue plasminogen activator antigen level over all cycle days examined.

CONCLUSION

Down-regulation of the fibrinolytic system was observed as estradiol levels increased. However, thrombin formation did not change, thus suggesting that elevated circulating estradiol alone does not predispose to a thromboembolic event.

Future directions in reproductive medicine

Major advances in assisted reproductive technology and fertility enhancement in the last decade are discussed in this article. Sustained research efforts have led to refinement in in vitro fertilization and related technologies. Other therapeutic innovations such as the use of newer pharmacologic agents and surgical procedures to preserve reproduction function are highlighted. Future directions and anticipated developments are briefly reviewed.