Living with metastatic breast cancer (LIMBER): experiences, quality of life, gaps in information, care and support of patients in the UK.

PURPOSE: To determine the experiences, information, support needs and quality of life of women in the UK living with metastatic breast cancer (MBC) to provide content for educational materials. METHODS: An online survey, hosted for 3 months on a UK MBC charity website, comprised sections covering issues such as communication about MBC treatment and management, helpful and less helpful things that healthcare professionals, family and friends did or said and completion of the Patient Roles and Responsibilities Scale (PRRS). RESULTS: A total of 143 patients participated; 48/143(33%) presented de novo; 54/143(38%) had been living with MBC > 2 years. PRRS analysis revealed that MBC imposed a serious impact upon most respondents' own caring abilities and social lives. A majority 98/139 (71%) wished they had known more about MBC before their diagnosis; 63/134(47%) indicated that they still did not fully understand their illness; merely 78/139(56%) had access to a specialist nurse and only 69/135(51%) had been offered any additional support. Respondents reported little consideration given to their lifestyle/culture during consultations and inconsistent information, support services, continuity of care or access to clinical trials. They commented upon things health care professionals/friends and family did or said that were useful and cited other behaviours that were especially unhelpful. CONCLUSIONS: MBC exerted a deleterious impact upon patients' activities of daily living which were exacerbated in part by significant gaps in support, communication and information. IMPLICATIONS FOR CANCER SURVIVORS: LIMBER results are informing the content of educational materials currently being developed for patients' formal and informal carers.

Simulation of Cocrystal Formation in Planetary Atmospheres: The C6H6:C2H2 Cocrystal Produced by Gas Deposition.

The formation of molecular cocrystals in condensed aerosol particles has been recently proposed as an efficient pathway for generation of complex organics in Titan's atmosphere. It follows that cocrystal precipitation may facilitate the transport of biologically important precursors to the surface to be sequestered in an organic karstic and sand environment. Recent laboratory studies on these planetary minerals have predominantly synthesized cocrystals by the controlled freezing of binary mixtures from the liquid phase, allowing for their structural and spectroscopic characterization. However, these techniques are perhaps not best representative of aerosol nucleation and growth microphysics in planetary atmospheres. Herein, we report the first synthesis of the known 1:1 C6H6:C2H2 cocrystal using vapor deposition methods onto a cryogenically cooled substrate. Subsequent transmission FTIR spectroscopy has confirmed the formation of the empirical C6H6:C2H2 cocrystal structure via the observation of diagnostic infrared spectral features. Predicted by periodic-DFT calculations, altered vibrational profiles depict a changing site symmetry of the C6H6 and C2H2 components after transition to the cocrystal unit cell geometry. The 80 K temperature of the cocrystal phase transition overlaps with the condensation curves obtained for both species in Titan's lower stratosphere, revealing that the cocrystal may act as an important environment for photo- and radio-lytic processes leading to the formation of higher order organics in Titan's atmosphere. Such solid-state astrochemistry can now be pursued in oxygen-free laboratory settings under (ultra)high vacuum using standard surface science setups.

Multiple genetic mechanisms lead to loss of functional TbAT1 expression in drug-resistant trypanosomes.

The P2 aminopurine transporter, encoded by TbAT1 in African trypanosomes in the Trypanosoma brucei group, carries melaminophenyl arsenical and diamidine drugs into these parasites. Loss of this transporter contributes to drug resistance. We identified the genomic location of TbAT1 to be in the subtelomeric region of chromosome 5 and determined the status of the TbAT1 gene in two trypanosome lines selected for resistance to the melaminophenyl arsenical, melarsamine hydrochloride (Cymelarsan), and in a Trypanosoma equiperdum clone selected for resistance to the diamidine, diminazene aceturate. In the Trypanosoma brucei gambiense STIB 386 melarsamine hydrochloride-resistant line, TbAT1 is deleted, while in the Trypanosoma brucei brucei STIB 247 melarsamine hydrochloride-resistant and T. equiperdum diminazene-resistant lines, TbAT1 is present, but expression at the RNA level is no longer detectable. Further characterization of TbAT1 in T. equiperdum revealed that a loss of heterozygosity at the TbAT1 locus accompanied loss of expression and that P2-mediated uptake of [(3)H]diminazene is lost in drug-resistant T. equiperdum. Adenine-inhibitable adenosine uptake is still detectable in a DeltaTbat1 T. b. brucei mutant, although at a greatly reduced capacity compared to that of the wild type, indicating that an additional adenine-inhibitable adenosine permease, distinct from P2, is present in these cells.

A randomized controlled study of whether the partner's presence in the operating room during neuraxial anesthesia for cesarean delivery reduces patient anxiety.

BACKGROUND: This study compared anxiety in two groups of women undergoing elective cesarean delivery to ascertain if their partner's presence during neuraxial anesthesia placement affected patients' overall anxiety levels. METHODS: Three hundred fifteen patient-partner dyads were randomized to two groups: group 1 partners were present in the operating room during neuraxial anesthesia placement while group 2 partners remained outside the operating room during placement. Before surgery, all patient-partner dyads completed a survey of demographics, anesthetic experiences and baseline anxiety. Anxiety levels were rated using a visual analogue scale (VAS) and the state portion of the Spielberger State-Trait Anxiety Inventory. RESULTS: The mean change in anxiety as measured by VAS among patients whose partners were present in the operating room for neuraxial anesthetic placement decreased from before to after the procedure (-4.5+/-25.8; P=0.03; 95% CI -8.55, -0.45); the mean change in anxiety in patients whose partners were not present did not alter significantly (+1.9 +/- 25.3; P=0.34; 95% CI 6.68, 12.12). Anxiety was increased among partners who were not present (+9.4, P<0.001). CONCLUSION: Although patients whose partners were present in the operating room at the time of neuraxial anesthesia placement reported less anxiety over the time of the study than did patients whose partners were not present, these differences were small and are not considered to be clinically important. Increased anxiety among partners who were not present at neuraxial placements warrants further study.

The role of glucocorticoids and progestins in inflammatory, autoimmune, and infectious disease.

A bidirectional communication exists between the CNS and the immune system. The autonomic nervous system, through neurotransmitters and neuropeptides, works in parallel with the hypothalamic-pituitary-adrenal axis through the actions of glucocorticoids to modulate inflammatory events. The immune system, through the action of cytokines and other factors, in turn, activates the CNS to orchestrate negative-feedback mechanisms that keep the immune response in check. Disruption of these interactions has been associated with a number of syndromes including inflammatory, autoimmune, and cardiovascular diseases, metabolic and psychiatric disorders, and the development of shock. The hypothalamic-pituitary-gonadal axis also plays an important part in regulating immunity through the secretion of sex hormones. Although numerous studies have established a role for immunomodulation by estrogen and testosterone, the role of progesterone is less well understood. Progesterone is crucial for reproductive organ development and maintenance of pregnancy, and more recent studies have clearly shown its role as an important immune regulator. The main focus of this review will be about the role of steroid hormones, specifically glucocorticoids and progesterone, in inflammatory responses and infectious diseases and how dysregulation of their actions may contribute to development of autoimmune and inflammatory disease.

Cryptosporidium and Giardia as foodborne zoonoses.

Cryptosporidium and Giardia are major causes of diarrhoeal disease in humans, worldwide and are major causes of protozoan waterborne diseases. Both Cryptosporidium and Giardia have life cycles which are suited to waterborne and foodborne transmission. There are 16 'valid'Cryptosporidium species and a further 33+ genotypes described. Parasites which infect humans belong to the Giardia duodenalis "type", and at least seven G. duodenalis assemblages are recognised. Cryptosporidium parvum is the major zoonotic Cryptosporidium species, while G. duodenalis assemblages A and B have been found in humans and most mammalian orders. In depth studies to determine the role of non-human hosts in the transmission of Cryptosporidium and Giardia to humans are required. The use of harmonised methodology and standardised and validated molecular markers, together with sampling strategies that provide sufficient information about all contributors to the environmental (oo)cyst pool that cause contamination of food and water, are recommended. Standardised methods for detecting (oo)cysts in water are available, as are optimised, validated methods for detecting Cryptosporidium in soft fruit and salad vegetables. These provide valuable data on (oo)cyst occurrence, and can be used for species and subspecies typing using appropriate molecular tools. Given the zoonotic potential of these organisms, epidemiological, source and disease tracking investigations involve multidisciplinary teams. Here, the role of the veterinarian is paramount, particularly in understanding the requirement for adopting comprehensive sampling strategies for analysing both sporadic and outbreak samples from all potential non-human contributors. Comprehensive sampling strategies increase our understanding of parasite population biology and structure and this knowledge can be used to determine what level of discrimination is required between isolates. Genetic exchange is frequent in C. parvum populations, leading to recombination between alleles at different loci, the generation of a very large number of different genotypes and a high level of resolution between isolates. In contrast, genetic exchange appears rare in Cryptosporidium hominis and populations are essentially clonal with far fewer combinations of alleles at different loci, resulting in a much lower resolution between isolates with many being of the same genotype. Clearly, more markers provide more resolution and high throughput sequencing of a variety of genes, as in multilocus sequence typing, is a way forward. Sub-genotyping tools offer increased discrimination, specificity and sensitivity, which can be exploited for investigating the epidemiology of disease, the role of asymptomatic carriers and contaminated fomites and for source and disease tracking for food and water contaminated with small numbers of (oo)cysts.

The large clostridial toxins from Clostridium sordellii and C. difficile repress glucocorticoid receptor activity.

We have previously shown that Bacillus anthracis lethal toxin represses glucocorticoid receptor (GR) transactivation. We now report that repression of GR activity also occurs with the large clostridial toxins produced by Clostridium sordellii and C. difficile. This was demonstrated using a transient transfection assay system for GR transactivation. We also report that C. sordellii lethal toxin inhibited GR function in an ex vivo assay, where toxin reduced the dexamethasone suppression of the proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha). Furthermore, the glucocorticoid antagonist RU-486 in combination with C. sordellii lethal toxin additively prevented glucocorticoid suppression of TNF-alpha. These findings corroborate the fact that GR is a target for the toxin and suggest a physiological role for toxin-associated GR repression in inflammation. Finally, we show that this repression is associated with toxins that inactivate p38 mitogen-activated protein kinase (MAPK).

Survival and invasiveness of astrocytomas promoted by erythropoietin.

OBJECT: The hypoxia-inducible pleiotropic hormone, erythropoietin (EPO), has recently been found to promote the development and survival of neurons and astrocytes. Since hypoxia has been implicated in the malignant progression of some human cancers, the authors investigated whether EPO signaling influenced the malignant properties of human astrocytoma cells. METHODS: Reverse transcriptase-polymerase chain reaction, Western blot analysis, and immunohistochemical studies were used to measure EPO and its receptor (EPOR). Cell viability, Matrigel invasion assays, metalloprotease assays, EPO neutralizing antibodies, and EPOR overexpression were used to study the biological actions of EPO. Expression of both EPO and EPOR was observed in the hypoxic regions and invasive margins of glioma specimens obtained at biopsy, and expression of EPOR correlated with the stage of the tumor. The EPOR was also functionally upregulated by hypoxia in cultured glioblastoma multiforme (GBM) cells. Both hypoxia and EPO protected cultured GBM cells from cisplatin cytotoxicity and promoted the invasiveness of GBM cells through Matrigel by potentiating metalloprotease activity. Hypoxia-enhanced cell invasion was attenuated in cells that overexpressed a nonfunctional EPOR. CONCLUSIONS: Hypoxia-inducible autocrine and paracrine EPO signaling participates in the malignant progression of GBMs.

Reversible inactivation of HIF-1 prolyl hydroxylases allows cell metabolism to control basal HIF-1.

Continuous hydroxylation of the HIF-1 transcription factor alpha subunit by oxygen and 2-oxoglutarate-dependent dioxygenases promotes decay of this protein and thus prevents the transcriptional activation of many genes involved in energy metabolism, angiogenesis, cell survival, and matrix modification. Hypoxia blocks HIF-1alpha hydroxylation and thus activates HIF-1alpha-mediated gene expression. Several nonhypoxic stimuli can also activate HIF-1, although the mechanisms involved are not well known. Here we show that the glucose metabolites pyruvate and oxaloacetate inactivate HIF-1alpha decay in a manner selectively reversible by ascorbate, cysteine, histidine, and ferrous iron but not by 2-oxoglutarate or oxygen. Pyruvate and oxaloacetate bind to the 2-oxoglutarate site of HIF-1alpha prolyl hydroxylases, but their effects on HIF-1 are not mimicked by other Krebs cycle intermediates, including succinate and fumarate. We show that inactivation of HIF-1 hydroxylation by glucose-derived 2-oxoacids underlies the prominent basal HIF-1 activity commonly seen in many highly glycolytic cancer cells. Since HIF-1 itself promotes glycolytic metabolism, enhancement of HIF-1 by glucose metabolites may constitute a novel feed-forward signaling mechanism involved in malignant progression.

Identification of a 40S Ribosomal protein (S17) that is differentially expressed between the macroschizont and piroplasm stages of Theileria annulata.

The nucleotide and protein sequence of the 40S ribosomal protein S17 (RibS17) of the protozoan parasite Theileria annulata has been determined. Southern blot analysis showed the gene was single copy and comparative sequence analysis revealed that the predicted polypeptide had high sequence homology with the RibS17 from other organisms. Northern blot analysis showed that there was a 3-fold increase in the level of RibS17 RNA between the macroschizont and the piroplasm stage of the lifecycle, whereas, there was no difference in expression between the sporozoite and the macroschizont stages. Antisera to the purified fusion protein, corresponding to the terminal 50 amino acids of the protein sequence, were raised in rabbits. Western analysis detected a polypeptide of the predicted size that was more abundant in the piroplasm stage compared with the macroschizont stage. Immunofluorescence analysis with the same antisera revealed a strong signal in the macroschizont and piroplasm stages, but the antiserum did not cross-react with the bovine host cells. The antisera did, however, cross-react with Toxoplasma gondii tachyzoites and Plasmodium falciparum merozoites. The possible functional significance of the stage related increase in abundance of a ribosomal protein is discussed.

TaCRK3 encodes a novel Theileria annulata protein kinase with motifs characteristic of the family of eukaryotic cyclin dependent kinases: a comparative analysis of its expression with TaCRK2 during the parasite life cycle.

The TaCRK3 gene from the bovine apicomplexan parasite Theileria annulata, encodes a 46 kDa polypeptide with strong homology to the eukaryotic family of cyclin-dependent kinases. TaCRK3 does not show significant alignment with any particular CDK group, other than the Pfmrk kinases from the related apicomplexans Plasmodium falciparum and Plasmodium yoelii. It has a putative bipartite nuclear localization signal and is located to parasite nuclei by IFAT. Protein levels are constitutive throughout differentiation of the intra-lymphocytic macroschizont. This contrasts with the expression pattern of TaCRK2 (Kinnaird et al., 1996, Mol. Microbiol., 22, 293-302) which is closely related to the eukaryotic CDK1 /2 families involved in regulation of cell cycle progression. TaCRK2 is also located to the parasite nuclei but has no nuclear localization signal and exhibits transient up-regulation in protein levels during mid-merogony. However compared to TaCRK3, it shows down-regulation near the end of merogony. We predict that TaCRK3 may have a role in regulation of gene transcription while TaCRK2 is more likely to be involved in control of parasite nuclear division.

Phenotype changes resulting in high-affinity binding of von Willebrand factor to recombinant glycoprotein Ib-IX: analysis of the platelet-type von Willebrand disease mutations.

To maintain hemostasis under shear conditions, there must be an interaction between the platelet glycoprotein (GP) Ib-IX receptor and the plasma ligand von Willebrand factor (vWf). In platelet-type von Willebrand disease (Pt-vWD), hemostasis is compromised. Two mutations in the GPIbalpha polypeptide chain have been identified in these patients-a glycine-233 to valine change and a methionine-239 to valine change. For this investigation, these mutant proteins have been expressed in a Chinese hamster ovary cell model system. Ligand-binding studies were performed at various concentrations of ristocetin, and adhesion assays were performed under flow conditions. The Pt-vWD mutations resulted in a gain-of-function receptor. vWf binding was increased at all concentrations of ristocetin examined, and adhesion on a vWf matrix was enhanced in terms of cell tethering, slower rolling velocity, and decreased detachment with increasing shear rate. Two other mutations were also introduced into the GPIbalpha chain. One mutation, encompassing both the Pt-vWD mutations, created an increase in the hydrophobicity of this region. The second mutation, involving a valine-234 to glycine change, decreased the hydrophobicity of this region. Both mutations also resulted in a gain-of-function receptor, with the double mutation producing a hyperreactive receptor for vWf. These data further support the hypothesis that ligand binding is regulated by conformational changes in the amino-terminal region of GPIbalpha, thereby influencing the stability of the GPIbalpha-vWf interaction.

Risk factors for perioperative adverse respiratory events in children with upper respiratory tract infections.

BACKGROUND: Anesthesia for the child who presents for surgery with an upper respiratory infection (URI) presents a challenge for the anesthesiologist. The Current prospective study was designed to determine the incidence of and risk factors for adverse respiratory events in children with URTs undergoing elective surgical procedures. METHODS: The study population included 1,078 children aged 1 month to 18 yr who presented for an elective surgical procedure. Parents were given a short questionnaire detailing their child's demographics, medical history, and presence of any symptoms of a URT. Data regarding the incidence and severity of perioperative respiratory events were collected prospectively. Adverse respiratory events (any episode of laryngospasm, bronchospasm, breath holding > 15 s, oxygen saturation < 90%, or severe cough) were recorded. In addition, parents were contacted 1 and 7 days after surgery to determine the child's postoperative course. RESULTS: There were no differences between children with active URIs, recent URIs (within 4 weeks), and asymptomatic children with respect to the incidences of laryngospasm and bronchospasm. However, children with active and recent URIs had significantly more episodes of breath holding, major desaturation (oxygen saturation < 90%) events, and a greater incidence of overall adverse respiratory events than children with no URIs. Independent risk factors for adverse respiratory events in children with active URIs included use of an endotracheal tube (< 5 yr of age), history of prematurity, history of reactive airway disease, paternal smoking, surgery involving the airway, the presence of copious secretions, and nasal congestion. Although children with URIs had a greater incidence of adverse respiratory events, none were associated with any long-term adverse sequelae. CONCLUSIONS: The current study identified several risk factors for perioperative adverse respiratory events in children with lulls. Although children with acute and recent URIs are at greater risk for respiratory complications, these results suggest that most of these children can undergo elective procedures without significant increase in adverse anesthetic outcomes.

Multiple microtubule alterations are associated with Vinca alkaloid resistance in human leukemia cells.

Vinca alkaloids are used extensively in the treatment of childhood acute lymphoblastic leukemia (ALL) and despite their usefulness, drug resistance remains a serious clinical problem. Vinca alkaloids bind to the beta-tubulin subunit of the alpha/beta-tubulin heterodimer and inhibit polymerization of microtubules. Recent studies have implicated altered beta-tubulin isotype expression and mutations in resistance to microtubule-stabilizing agents. Microtubule-associated protein (MAP) MAP4 binds to and stabilizes microtubules, and increased expression is associated with decreased sensitivity to microtubule-depolymerizing agents. To address the significance of beta-tubulin and MAP4 alterations in childhood ALL, two CCRF-CEM-derived Vinca alkaloid resistant cell lines, VCR R (vincristine) and VLB100 (vinblastine), were examined. Decreased expression of class III beta-tubulin was detected in both VCR R and VLB100 cells. VCR R cells and to a lesser extent VLB100 cells expressed increased levels of MAP4 protein. Increased microtubule stability was observed in these VCR R cells as identified by the high levels of polymerized tubulin (45.6 +/- 2.6%; P < 0.005) compared with CEM and VLB100 cells (24.7 +/- 3.3% and 24.7 +/- 2.5%, respectively). Expression was associated with a single MAP4 isoform in the polymerized microtubule fraction in CEM and VCR cells. In contrast, VLB100 cells expressed a lower molecular weight isoform in the polymerized fraction. Two-dimensional-PAGE and immunoblotting revealed marked posttranslational changes in class I beta-tubulin in VCR R cells not evident in CEM cells. Sequencing of the beta-tubulin (HM40) gene identified a point mutation in VCR R cells in nucleotide 843 (CTC-->ATC; Leu(240)-->Ile) that was not present in CEM or VLB100 cells. This mutation resides in a region of beta-tubulin that lies in close proximity to the alpha/beta tubulin interface. Multiple alterations related to normal microtubule function were identified in ALL cells selected for resistance to Vinca alkaloids, and these alterations may provide important insight into mechanisms mediating resistance to Vinca alkaloids.

Markedly diminished drug resistance-inducing properties of vinflunine (20',20'-difluoro-3',4'-dihydrovinorelbine) relative to vinorelbine, identified in murine and human tumour cells in vivo and in vitro.

PURPOSE: Vinflunine (VFL) is a novel Vinca alkaloid with markedly superior experimental in vivo antitumour activity to its parent molecule, vinorelbine (Navelbine, NVB), against a panel of murine and human tumours. The aim of this study was to establish whether there are differences in the rate and extent of development of resistance, both in vivo and in vitro, to these two newer Vinca alkaloids under identical selection conditions. METHODS: Using P388 leukaemia cells in vivo, it was evident that VFL induced drug resistance far less readily than NVB, as shown by the number of passages required to select for total resistance. Under in vitro conditions, using A549 human lung carcinoma cells, it was also clearly shown by drug sensitivity determinations that VFL was a less-potent inducer of drug resistance than NVB. Resistance resulting from either in vivo or in vitro selection was associated with a classic multidrug resistance profile. Further characterization of the drug-resistance phenotype of the most highly resistant A549 sublines showed that the level of total beta-tubulin expression appeared to be modified exclusively in the NVB-resistant cells. CONCLUSION: The clear demonstration that resistance to VFL developed far less readily than resistance to NVB both in vivo and in vitro may have potential clinical implications.

Pain management in children with and without cognitive impairment following spine fusion surgery.

BACKGROUND: We compared pain assessment and management practices in children with and without cognitive impairment (CI) undergoing spine fusion surgery. METHODS: The medical records of 42 children (19 with CI and 23 without) were reviewed and data related to demographics, surgery, pain assessment and management, and side-effects were recorded. RESULTS: Fewer children with CI were assessed for pain on postoperative days (POD) 0-4 compared to those without CI (P < 0.002). Self-report was used for 81% of pain assessments in children without CI, while a behavioural tool was used for 75% of assessments in cognitively impaired children. Children with CI received smaller total opioid doses on POD 1-3 compared to those without CI (P < or = 0.02). Furthermore, children without CI received patient/nurse-controlled analgesia for more postoperative days than children with CI (P=0.02). CONCLUSION: Our data demonstrate a discrepancy in pain management practices in children with and without CI following spine fusion.

Phenotypic features, androgen receptor binding, and mutational analysis in 278 clinical cases reported as androgen insensitivity syndrome.

Androgen insensitivity syndrome (AIS) is the most common single entity that results in male under-masculinization, but large cohort studies of AIS have rarely been performed. Over the last decade, nationwide cooperation between pediatric endocrinologists in the United Kingdom has allowed the creation of a database of cases of intersex and ambiguous genitalia where detailed clinical information on every notified case has been collected via a questionnaire. Among the 816 entries recorded by January 1999, there were 105 clinically diagnosed cases of complete AIS (CAIS) and 173 cases of partial AIS (PAIS). A masculinization score was devised by scoring the external phenotype, and a score of 12 represented normal masculinization. Androgen receptor (AR) binding was determined by studying binding capacity (Bmax) and receptor affinity (K(d)), and cases were classified as either zero, abnormal, or normal binding. Mutation screening of all eight exons of the AR gene was performed by single-strand conformational polymorphism analysis, followed by direct DNA sequencing. All cases of PAIS presented within the first month of birth. The median age at presentation of children with CAIS was 1 yr (P10,P90: 0.1,10.4). The testes were palpable in the labioscrotal folds or the inguinal region in 77% and 41% of cases of CAIS and PAIS, respectively. There was marked overlap between the masculinization score of those children with PAIS reared as girls [2.5(P10,P90:1, 6)] and those reared as boys [3(P10,P90:2, 7.5)]. Gonadectomy was performed prepubertally in 66% and postpubertally in 29% of the cases of CAIS. The median age of the latter group was older at 14 yr (P10,P90:0.1,18). No cases of malignancy or carcinoma in situ were reported in the 121 cases of AIS where histology results were available. Biochemical endocrine investigations were reported to have been performed in a greater number of cases of PAIS than CAIS (98% vs. 48%). AR binding was abnormal in 44 of 51 (86%) and 40 of 113 (35%) cases of CAIS and PAIS, respectively. Zero binding was encountered in 29 of 43 (67%) and 1 of 55 (2%) cases of CAIS and PAIS, respectively. Mutational analysis of the AR gene, performed in 102 index cases was positive in 57 of 69 (83%) cases of CAIS and 12 of 43 (28%) cases of PAIS. In 24 of these cases, the mutation identified was novel. The mutations in PAIS cases were all missense, whereas in CAIS the mutations were more diverse. AR binding was only normal in 3 of 69 mutation-positive cases. In the PAIS group, mutation-positive cases had a significantly higher Kd and Bmax compared to the mutation negative cases. The clinical diagnosis of AIS can be confirmed in a significant number of cases by a combination of androgen-binding studies and mutational analysis. There is some correlation between the phenotypic features and the abnormalities discovered on mutational analysis of the AR gene, but there is a need to improve this further by developing optimal bioassays of AR function. The phenotypic heterogeneity among clinically diagnosed cases of AIS emphasizes the need for appropriate comprehensive evaluation of male under-masculinization.

Perioperative considerations for the child with an upper respiratory tract infection.

The decision to cancel or proceed with elective surgery for the child with an upper respiratory tract infection (URI) has been a source of debate among pediatric anesthesiologists, nurse anesthetists, and perianesthesia nurses for many years. Although some studies suggest that anesthesia for the child with a URI increases the risk of perioperative respiratory complications, others suggest that these complications are easily managed and are not associated with any adverse sequelae. This article describes the pathogenesis of viral respiratory tract infections, reviews the literature regarding anesthesia and URIs, and discusses the assessment and management of the child who presents for elective surgery while harboring a URI. It is hoped that this information will be important to perianesthesia nurses and anesthesia providers in making decisions regarding proceeding or cancelling surgery for children with URIs and in optimizing their perioperative management.

A high level of mixed Trypanosoma brucei infections in tsetse flies detected by three hypervariable minisatellites.

The issue of whether genetic exchange occurs at a significant frequency in natural populations of Trypanosoma brucei is controversial and one of the arguments against a high frequency has been the apparent lack of host infections with mixtures of trypanosome genotypes. Three minisatellite markers (MS42, CRAM, 292) within the coding regions of three genes have been identified and PCR based methods developed for detecting variation at these loci using crude lysates of infected blood as templates. Initial PCR analysis, using primers flanking the repeats, of DNA from two cloned stocks of the parasite has shown that two DNA fragments of different size were amplified from each stock. Analysis of the inheritance of these fragments into the F1 progeny of crosses demonstrated that the different size fragments were alleles that segregated in a Mendelian manner. The alleles at each of the three loci segregated independently consistent with their localisation on three different chromosomes. Analysis of a series of cloned isolates from tsetse flies showed that these loci were highly variable giving heterozygosities of 94% and the identification of 12 distinct alleles in a sample of 17 cloned isolates. In order to determine whether isolates are heterogeneous in terms of trypanosome genotype, the allelic variation at these three loci was examined in uncloned samples from tsetse flies isolated in Kiboko, Kenya and Lugala, Uganda. A significant proportion of the isolates (36% in Lugala and 47% in Kiboko) contained more than two alleles at one or more of the loci thus demonstrating that a high proportion of tsetse flies were infected with more than one genotype of trypanosomes. This was established, unequivocally, for two isolates by generating a series of cloned trypanosome lines from each and determining the genotype of each clone; one isolate (927) contained seven different genotypes with a high proportion of the possible combinations of alleles at each locus. These results indicate the possibility of frequent genetic exchange in the field, they imply that a significant proportion of mammalian hosts must contain mixtures of different trypanosome genotypes and they demonstrate the advantages of using minisatellite markers for the analysis of the population structure of T. brucei.

Pain relief in children following outpatient surgery.

STUDY OBJECTIVE: To evaluate perioperative analgesia, prescription patterns, pain relief, and parental care of children undergoing outpatient surgery. DESIGN: Prospective data collection and parental interview. SETTING: Large tertiary care, university-based medical center. PATIENTS: 471 children aged between 10 months and 18 years who underwent an outpatient surgical procedure expected to be associated with pain. MEASUREMENTS AND MAIN RESULTS: All perioperative data regarding analgesia, antiemetics, postoperative pain scores, and discharge prescriptions were recorded. Parents were telephoned 24 hours following surgery, and data concerning their child's pain relief, analgesic and antiemetic usage, and their ability to care for their child were obtained. Of the 460 patients questioned, 97% were described by their parents as having adequate, good, or very good pain relief (acceptable) during the first 24 hours postoperatively, whereas only 15 (3%) had poor pain relief (unacceptable). All patients received some form of analgesia intraoperatively. The children with poor pain relief were more likely to have experienced postoperative nausea and vomiting (p = 0.01) and were more difficult to care for at home (p < 0.0001). In a subset of 185 patients who had genitourinary procedures, those who received regional analgesia reported better pain relief (p = 0.05). CONCLUSIONS: Despite a wide range of surgical procedures being performed on children on an ambulatory basis, current selection of patients for outpatient surgery is appropriate given the ability of the parents to manage their children's pain and to care for their children at home.