Two alternative methods for the retrieval of somatic cell populations from the mouse ovary.

Many modern techniques employed to uncover the molecular fundamentals underlying biological processes require dissociated cells as their starting point/substrate. Investigations into ovarian endocrinology or folliculogenesis, therefore, necessitate robust protocols for dissociating the ovary into its constituent cell populations. While in the mouse, methods to obtain individual, mature follicles are well-established, the separation and isolation of single cells of all types from early mouse follicles, including somatic cells, has been more challenging. Herein we present two methods for the isolation of somatic cells in the ovary. These methods are suitable for a range of applications relating to the study of folliculogenesis and mouse ovarian development. First, an enzymatic dissociation utilising collagenase and a temporary, primary cell culture step using neonatal mouse ovaries which yields large quantities of granulosa cells from primordial, activating, and primary follicles. Second, a rapid papain dissociation resulting in a high viability single cell suspension of ovarian somatic cells in less than an hour, which can be applied from embryonic to adult ovarian samples. Collectively these protocols can be applied to a broad array of investigations with unique advantages and benefits pertaining to both.

Signal transducer and activator of transcription (STAT) 1 and STAT3 are expressed in the human ovary and have Janus kinase 1-independent functions in the COV434 human granulosa cell line.

Ovarian granulosa cells are fundamental for oocyte maintenance and maturation. Recent studies have demonstrated the importance of members of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signalling pathway in the granulosa cell population of mouse and horse ovaries, with perturbation of JAK1 signalling in the mouse shown to impair oocyte maintenance and accelerate primordial follicle activation. The presence and role of the JAK/STAT pathway in human granulosa cells has yet to be elucidated. In this study, expression of JAK1, STAT1 and STAT3 was detected in oocytes and granulosa cells of human ovarian sections from fetal (40 weeks gestation) and premenopausal ovaries (34-41 years of age; n=3). To determine the effects of JAK1 signalling in granulosa cells, the human granulosa-like cell line COV434 was used, with JAK1 inhibition using ruxolitinib. Chemical inhibition of JAK1 in COV434 cells with 100nM ruxolitinib for 72h resulted in significant increases in STAT3 mRNA (P=0.034) and p-Y701-STAT1 protein (P=0.0117), demonstrating a role for JAK1 in modulating STAT in granulosa cells. This study implicates a conserved role for JAK/STAT signalling in human ovary development, warranting further investigation of this pathway in human granulosa cell function.

Primary Ciliary Dyskinesia Due to Microtubular Defects is Associated with Worse Lung Clearance Index.

PURPOSE: Primary ciliary dyskinesia (PCD) is characterised by repeated upper and lower respiratory tract infections, neutrophilic airway inflammation and obstructive airway disease. Different ultrastructural ciliary defects may affect lung function decline to different degrees. Lung clearance index (LCI) is a marker of ventilation inhomogeneity that is raised in some but not all patients with PCD. We hypothesised that PCD patients with microtubular defects would have worse (higher) LCI than other PCD patients. METHODS: Spirometry and LCI were measured in 69 stable patients with PCD. Age at testing, age at diagnosis, ethnicity, ciliary ultrastructure, genetic screening result and any growth of Pseudomonas aeruginosa was recorded. RESULTS: Lung clearance index was more abnormal in PCD patients with microtubular defects (median 10.24) than those with dynein arm defects (median 8.3, p = 0.004) or normal ultrastructure (median 7.63, p = 0.0004). Age is correlated with LCI, with older patients having worse LCI values (p = 0.03, r = 0.3). CONCLUSION: This study shows that cilia microtubular defects are associated with worse LCI in PCD than dynein arm defects or normal ultrastructure. The patient's age at testing is also associated with a higher LCI. Patients at greater risk of obstructive lung disease should be considered for more aggressive management. Differences between patient groups may potentially open avenues for novel treatments.

Interobserver variability in upgraded and non-upgraded BI-RADS 3 lesions.

AIM: To evaluate interobserver variability in the assessment of Breast Imaging-Reporting and Data System (BI-RADS) 3 mammographic lesions, and to determine if the initial evaluation of upgraded BI-RADS 3 lesions was appropriate. MATERIALS AND METHODS: Retrospective review of the mammography database (1/1/2004-12/31/2008) identified 1,188 screen-detected BI-RADS 3 lesions, 60 (5.1%) were upgraded to BI-RADS 4/5 during surveillance (cases). Cases were matched to 60 non-upgraded BI-RADS 3 lesions (controls) by lesion type, laterality, and year. Available studies were assessed separately by two radiologists blinded to outcomes. RESULTS: Eighty-two studies were available (43 cases, eight malignancies, and 39 controls). Reader 1 assessed 18/82 (22%) as BI-RADS 0, 13 cases, five controls; 35/82 (42.7%) as BI-RADS 2, 11 cases, 24 controls; 7/82 (8.5%) BI-RADS 3, four cases, three controls; 22/82 BI-RADS 4, 15 cases, seven controls. Reader 2 assessed 8/82 (9.8%) as BI-RADS 0, four cases, four controls; 27 (32.9%) BI-RADS 2, 11 cases, 16 controls; 33 (40.2%) BI-RADS 3, 19 cases, 14 controls; 14 (17%) BI-RADS 4, nine cases, five controls. For cancers, reader 1 assessed two BI-RADS 0, one BI-RADS 2, one BI-RADS 3, and four BI-RADS 4; reader 2 assessed two BI-RADS 2, four BI-RADS 3, and two BI-RADS 4. Reasons for BI-RADS 0 assessment included incomplete mammographic views, lack of ultrasound, and failure to include the lesion on follow-up imaging. Reasons for BI-RADS 4 assessment included suspicious morphology or instability. CONCLUSION: There is much interobserver variability in the assessment of BI-RADS 3 lesions. Many BI-RADS 3 lesions were judged as incompletely evaluated on blinded review.

From inflamm-aging to immune-paralysis: a slippery slope during aging for immune-adaptation.

Aging is accompanied by many physiological changes including those in the immune system. These changes are designated as immunosenescence indicating that age induces a decrease in immune functions. However, since many years we know that some aspects are not decreasing but instead are increasing like the pro-inflammatory activity by the innate immune cells, especially by monocytes/macrophages. Recently it became evident that these cells may possess a sort of memory called trained memory sustained by epigenetic changes occurring long after even in the absence of the initiator aggressor. In this review we are reviewing evidences that such changes may occur in aging and describe the relationship between inflamm-aging and immunosenescence as an adaptation/remodelling process leading on one hand to increased inflammation and on the other to decreased immune response (immune-paralysis) mastered by the innate immune system. These changes may collectively induce a state of alertness which assure an immune response even if ultimately resulting in age-related deleterious inflammatory diseases.

Variability of human immunodeficiency virus-1 in the female genital reservoir during genital reactivation of herpes simplex virus type 2.

Clinical and subclinical genital herpes simplex virus type 2 (HSV-2) reactivations have been associated with increases in human immunodeficiency virus (HIV)-1 genital shedding. Whether HSV-2 shedding contributes to the selection of specific genital HIV-1 variants remains unknown. We evaluated the genetic diversity of genital and blood HIV-1 RNA and DNA in 14 HIV-1/HSV-2-co-infected women, including seven with HSV-2 genital reactivation, and seven without as controls. HIV-1 DNA and HIV-1 RNA env V1-V3 sequences in paired blood and genital samples were compared. The HSV-2 selection pressure on HIV was estimated according to the number of synonymous substitutions (dS), the number of non-synonymous substitutions (dN) and the dS/dN ratio within HIV quasi-species. HIV-1 RNA levels in cervicovaginal secretions were higher in women with HSV-2 replication than in controls (p0.02). Plasma HIV-1 RNA and genital HIV-1 RNA and DNA were genetically compartmentalized. No differences in dS, dN and the dS/dN ratio were observed between the study groups for either genital HIV-1 RNA or plasma HIV-1 RNA. In contrast, dS and dN in genital HIV-1 DNA were significantly higher in patients with HSV-2 genital reactivation (p <0.01 and p <0.05, respectively). The mean of the dS/dN ratio in genital HIV-1 DNA was slightly higher in patients with HSV-2 genital replication, indicating a trend for purifying selection (p 0.056). HSV-2 increased the genetic diversity of genital HIV-1 DNA. These observations confirm molecular interactions between HSV-2 and HIV-1 at the genital tract level.

Effects of subthalamic stimulation on speech of consecutive patients with Parkinson disease.

OBJECTIVE: Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for advanced Parkinson disease (PD). Following STN-DBS, speech intelligibility can deteriorate, limiting its beneficial effect. Here we prospectively examined the short- and long-term speech response to STN-DBS in a consecutive series of patients to identify clinical and surgical factors associated with speech change. METHODS: Thirty-two consecutive patients were assessed before surgery, then 1 month, 6 months, and 1 year after STN-DBS in 4 conditions on- and off-medication with on- and off-stimulation using established and validated speech and movement scales. Fifteen of these patients were followed up for 3 years. A control group of 12 patients with PD were followed up for 1 year. RESULTS: Within the surgical group, speech intelligibility significantly deteriorated by an average of 14.2%±20.15% off-medication and 16.9%±21.8% on-medication 1 year after STN-DBS. The medical group deteriorated by 3.6%±5.5% and 4.5%±8.8%, respectively. Seven patients showed speech amelioration after surgery. Loudness increased significantly in all tasks with stimulation. A less severe preoperative on-medication motor score was associated with a more favorable speech response to STN-DBS after 1 year. Medially located electrodes on the left STN were associated with a significantly higher risk of speech deterioration than electrodes within the nucleus. There was a strong relationship between high voltage in the left electrode and poor speech outcome at 1 year. CONCLUSION: The effect of STN-DBS on speech is variable and multifactorial, with most patients exhibiting decline of speech intelligibility. Both medical and surgical issues contribute to deterioration of speech in STN-DBS patients. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that STN-DBS for PD results in deterioration in speech intelligibility in all combinations of medication and stimulation states at 1 month, 6 months, and 1 year compared to baseline and to control subjects treated with best medical therapy.

Experimental autoimmune encephalomyelitis-induced upregulation of tumor necrosis factor-alpha in the dorsal root ganglia.

BACKGROUND: Multiple sclerosis (MS) is a chronic, neurological disease characterized by targeted destruction of central nervous system (CNS) myelin. The autoimmune theory is the most widely accepted explanation of disease pathology. Circulating Th(1) cells become activated by exposure to CNS-specific antigens such as myelin basic protein. The activated Th(1) cells secrete inflammatory cytokines, which are pivotal for inflammatory responses. We hypothesize that enhanced production of inflammatory cytokines triggers cellular events within the dorsal root ganglia (DRG) and/or spinal cord, facilitating the development of neuropathic pain (NPP) in MS. NPP, the second worst disease-induced symptom suffered by patients with MS, is normally regulated by DRG and/or spinal cord. OBJECTIVE: To determine gene and protein expression levels of tumor necrosis factor-alpha (TNFalpha) within DRG and/or spinal cord in an animal model of MS. METHODS: Experimental autoimmune encephalomyelitis (EAE) was induced in adolescent female Lewis rats. Animals were sacrificed every 3 days post-disease induction. DRG and spinal cords were harvested for protein and gene expression analysis. RESULTS: We show significant increases in TNFalpha expression in the DRG and of EAE animals at peak disease stage, as assessed by clinical symptoms. CONCLUSION: Antigen-induced production of inflammatory cytokines such as TNFalpha within the DRG identifies a potential novel mechanism for MS-induced NPP.

Epidemiology and clinical features of amyotrophic lateral sclerosis in Ireland between 1995 and 2004.

BACKGROUND: We conducted a prospective, population based study to examine trends in incidence and prevalence of amyotrophic lateral sclerosis (ALS) in Ireland from 1995 to 2004. METHODS: The Irish ALS Register was used to identify Irish residents diagnosed with ALS between the 3 year period from 1 January 1995 to 31 December 1997 and the 3 year period from 1 January 2002 to 31 December 2004. RESULTS: 465 Irish residents were diagnosed with ALS during the study periods. The annual incidence rate of ALS in Ireland remained stable over this time (2.0 cases per 100,000 person-years; 95% CI 1.9, 2.2). Median survival of Irish ALS patients was 16.4 months and did not change during the study period. Demographics and clinical features of the incident and prevalent Irish ALS cohorts were markedly different.

Recovery of vision and pupil responses in optic neuritis and multiple sclerosis.

The recovery of visual performance and pupil responses were investigated in patients with demyelinating optic neuritis (ON) and multiple sclerosis (MS). The pupil constriction amplitude and the time delay (latency) of the pupil response were measured in 14 patients with a history of unilateral ON in response to either achromatic (luminance) or chromatic (isoluminant) stimulus modulation. Five of these subjects were diagnosed later with MS. In addition, we measured detection thresholds for achromatic stimuli using standard visual field perimetry and chromatic thresholds using a new colour assessment and diagnosis (CAD) test that isolates the use of colour signals. The results show that, despite significant improvements in visual function following the acute phase (as assessed using visual acuity and fields), significant pupil response deficits remain. The findings also demonstrate that accurate measurements of pupil responses and chromatic thresholds can reveal deficits that remain undetected with more conventional techniques. These preliminary findings suggest that the techniques described here can provide useful information about remitting and relapsing demyelinative phases, often observed during MS and ON.

Mycoplasma genitalium: an organism commonly associated with cervicitis among west African sex workers.

OBJECTIVES: To identify the contribution of Mycoplasma genitalium to the aetiology of cervicitis in sub-Saharan Africa and its relative importance in the overall burden of sexually transmitted infections among female sex workers (FSW). METHODS: The study population consisted of FSW recruited in Ghana and Benin during the initial visit of a randomised controlled trial. A questionnaire was administered, a pelvic examination carried out, and cervical samples obtained for detection of M genitalium, Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis. Clinical signs potentially indicating cervicitis were cervical discharge, pus on the cervical swab, bleeding after sampling, and inflammatory cervix. RESULTS: Among 826 FSW, 26.3% were infected with M genitalium. N gonorrhoeae was strongly and independently associated with each of the four signs of cervicitis (adjusted odds ratios (AOR): 4.1 to 6.0). The AOR for C trachomatis were intermediate (1.3-4.1) and the AOR for M genitalium were lower (between 1.6 and 1.8) but statistically significant (p< or =0.05) for each sign. CONCLUSIONS: M genitalium is weakly associated with signs of cervicitis in west African FSW but is highly prevalent.

A novel candidate region for ALS on chromosome 14q11.2.

Sequence variations with biologic effect in ALS have been identified in the gene for vascular endothelial growth factor (VEGF). The gene for a related protein, angiogenin, lies on chromosome 14q11.2. Analysis of the angiogenin (ANG) gene in the authors' population has demonstrated a significant allelic association with the rs11701 single nucleotide polymorphism (SNP) and identified a novel mutation in two individuals with sporadic ALS that potentially inhibits angiogenin function. These observations propose a candidate region for ALS on chromosome 14q11.2 and suggest that other genes with similar function to VEGF may be important in the pathogenesis of ALS.

Low prevalence of cervical infections in women with vaginal discharge in west Africa: implications for syndromic management.

OBJECTIVES: To measure prevalence and risk factors for cervical infections among a large sample of women consulting for vaginal discharge in west Africa and to evaluate its syndromic management through a two visit algorithm. METHODS: In 11 health centres in Bénin, Burkina Faso, Ghana, Guinée, and Mali 726 women who presented with a vaginal discharge without abdominal pain and who denied being a sex worker (SW) were enrolled. Cervical samples were tested for the detection of Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) with polymerase chain reaction (PCR) assays. All participants were treated with single dose (2 g) metronidazole and clotrimazole cream for 3 days. They were randomised to be told either to come back on day 7 only if there was no improvement in the discharge (group A), or to come back on day 7 regardless of response to treatment (group B). RESULTS: Overall, the prevalence of NG and CT was only 1.9% (14/726) and 3.2% (23/726) respectively. Risk factors previously recommended by the WHO were not associated with the presence of cervical infection, with the exception of the number of sex partners in the past 3 months. When taken together, these risk factors had a positive predictive value of only 6.4% to identify cervical infections. Prevalence of cervical infection was not higher in women who came back on day 7, regardless of the strategy used. Prevalence of NG/CT was lower in Ghana and Bénin (5/280, 1.8%), where comprehensive interventions for SW have been ongoing for years, than in the three other countries (27/446, 6.1%, p = 0.01). CONCLUSIONS: NG and CT infections are uncommon in west African women who consult for vaginal discharge and who are not SW. Syndromic management of vaginal discharge should focus on the proper management of vaginitis. The control of gonococcal and chlamydial infection should be redesigned around interventions focusing on sex workers.

Access to health services in Ireland for people with Multiple Sclerosis and Motor Neurone Disease.

We conducted a telephone questionnaire to determine the utilisation of hospital and community based services by patients with Motor Neurone Disease and Multiple Sclerosis in Ireland. 94 MND and 188 MS patients participated in the study. MND patients were more likely to have free medical care than MS patients, despite legislation favouring the converse. Severely disabled MND patients were more successful at accessing free community-based services than were severely disabled MS patients. Private medical insurance conferred no advantage when obtaining services or purchasing equipment. Many patients were unaware of the specific roles of the various clinical professionals. There are significant deficiencies in patients' ability to access multidisciplinary services. Voluntary organisations often bridge the gap in service provision. An investment in services for people with chronic neurological disability is urgently required.

Sexually transmitted infections in male clients of female sex workers in Benin: risk factors and reassessment of the leucocyte esterase dipstick for screening of urethral infections.

OBJECTIVES: (1) To assess risk factors for urethral infections with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis among male clients of female sex workers (FSWs) in Benin; (2) to study the validity of LED testing of male urine samples compared to a highly sensitive gold standard (PCR) for the diagnosis of urethral infections with the organisms cited above. METHODS: Male clients of FSWs (n=404) were recruited on site at prostitution venues in Cotonou, Benin, between 28 May and 18 August 1998. A urine sample was obtained from each participant just before he visited the FSW, and tested immediately using a leucocyte esterase dipstick (LED) test. It was then tested for HIV using the Calypte EIA with western blot confirmation, and for C. trachomatis, N. gonorrhoeae, and T. vaginalis by PCR. After leaving the FSW's room, participants were interviewed about demographics, sexual behaviour, STI history and current symptoms and signs, and were examined for urethral discharge, genital ulcers, and inguinal lymphadenopathies. RESULTS: STI prevalences were: C. trachomatis, 2.7%; N. gonorrhoeae, 5.4%; either chlamydia or gonorrhoea 7.7%; T. vaginalis 2.7%; HIV, 8.4%. Lack of condom use with FSWs and a history of STI were independently associated with C. trachomatis and/or N. gonorrhoeae infection. Over 80% of these infections were in asymptomatic subjects. The overall sensitivity, specificity, positive and negative predictive values of the LED test for detection of either C. trachomatis or N. gonorrhoeae were 48.4%, 94.9%, 44.1%, and 95.7%, respectively. In symptomatic participants (n=22), all these parameters were 100% while they were 47.4%, 94.7%, 37.5%, and 96.4% in asymptomatic men (n=304). CONCLUSIONS: Since most STIs are asymptomatic in this population, case finding programmes for gonorrhoea and chlamydia could be useful. The performance characteristics of the LED test in this study suggest that it could be useful to detect asymptomatic infection by either C. trachomatis or N. gonorrhoeae in high risk men.

Effect of a multidisciplinary amyotrophic lateral sclerosis (ALS) clinic on ALS survival: a population based study, 1996-2000.

BACKGROUND: In recent years, there has been a paradigm shift in the method of healthcare delivery to amyotrophic lateral sclerosis (ALS) patients with the emergence of multidisciplinary ALS clinics that cater exclusively for patients with this condition. The impact of multidisciplinary management has not been previously evaluated. METHODS: Using data from the Irish ALS Register, we conducted a prospective, population based study of all ALS cases diagnosed in Ireland over a five year period to evaluate the effectiveness of a multidisciplinary clinic on ALS survival. RESULTS: Eighty two (24%) patients attended the multidisciplinary ALS clinic, with the remaining 262 (76%) cases followed in a general neurology clinic. The ALS clinic cohort was an average of five years younger (60.1 v 65.6 years) and were more likely to receive riluzole than the general neurology cohort (99% v 61%). The median survival of the ALS clinic cohort was 7.5 months longer than for patients in the general neurology cohort (logrank = 15.4, p < 0.0001). Overall, one year mortality was decreased by 29.7%. Prognosis of bulbar onset patients was extended by 9.6 months if they attended the ALS clinic. Using multivariate analysis, attendance at the ALS clinic was an independent covariate of survival (HR = 1.47, p = 0.02). CONCLUSIONS: ALS patients who received their care at a multidisciplinary clinic had a better prognosis than patients attending a general neurology clinic. The data suggest that active and aggressive management enhances survival, particularly among ALS patients with bulbar dysfunction. The effect of clinic type must be considered in future clinical trials design.

Correlation between culture testing of swabs and ligase chain reaction of first void urine from patients recently treated for Chlamydia trachomatis.

We assessed the correlation between ligase chain reaction (LCR) on first void urine (FVU) and cultures of urethral and cervical swabs to detect chlamydia during three post-treatment follow up visits for 10 men and 19 women with genital chlamydial infections who had been treated with azithromycin or doxcycline.

Mycoplasma genitalium is not associated with adverse outcomes of pregnancy in Guinea-Bissau.

OBJECTIVE: To evaluate the impact of Mycoplasma genitalium on the outcome of pregnancy. METHODS: Cervical samples from women who had previously participated in a case-control study (designed to assess the impact of syphilis and HIV-2 on the outcome of pregnancy in Guinea-Bissau) were processed using a PCR assay to detect the presence of M genitalium. Controls were women who had delivered a term neonate with a birth weight over 2500 g. Cases were classified into four groups of mothers according to the outcome of pregnancy: stillbirths, spontaneous abortions, premature deliveries, and small for gestational age (SGA) babies. RESULTS: Among the 1014 women included in this study, 6.2% were infected with M genitalium. M genitalium infection was not significantly associated with any of the adverse outcomes of pregnancy studied. Odds ratios (OR) for premature or SGA delivery in the presence of M genitalium infection were 1.37 (95% CI 0.69 to 2.60) and 0.44 (95% CI 0.01 to 2.75), respectively. For abortions and stillbirths, OR were respectively 0.61 (95% CI 0.07 to 2.51) and 1.07 (95% CI 0.42 to 2.42). CONCLUSION: M genitalium appears not to have a deleterious impact on the outcome of pregnancy.

HIV infection among sex workers in Accra: need to target new recruits entering the trade.

OBJECTIVE: Description of the epidemiology of HIV infection among sex workers (SW) in Accra, Ghana. METHODS: In all, 1013 SW working out of their homes ( seaters ) or finding customers in bars, hotels, brothels or on the street ( roamers ) were interviewed and tested for HIV. RESULTS: Overall, prevalence of HIV infection was nearly 50% (506 of 1013), varying from 26% (133 of 507) among the roamers to 74% (368 of 496) among the seaters. Profound differences were noted between these two categories of SW with regard to age, number of clients per day, price per instance of intercourse, condom use, and other characteristics. Respectively, 27% and 58% of roamers and seaters were infected with HIV within their first 6 months of sex work, despite a limited number of unprotected sex acts with seropositive clients. Independent risk factors for HIV infection varied between types of SW: age among the roamers; region of origin and duration of sex work among the seaters; number of clients per day, and presence of current or past genital ulcer and gonococcal cervicitis in both groups. CONCLUSION: In Accra, considerable heterogeneity exists in the population of SWs. In both categories of SW, new recruits become rapidly infected with HIV after entering the trade. The 25-fold higher prevalence of HIV among SWs than in the general adult population suggests that in Accra, as in many cities of West Africa, a high fraction of new cases of HIV infection continue to be acquired from SWs. Intervention programs targeting SW should be an essential component of national AIDS control strategies. Special efforts should be made to identify and offer preventive services to new sex workers.

Postoperative nausea and vomiting--a review.

Post operative nausea and vomiting (PONV) remains an unpleasant and persistent problem for patients undergoing surgery. In fact PONV are among the most important factors contributing to delay in discharge of patients and an increase in unanticipated admissions after ambulatory surgery. Anesthesia providers are most often blamed for PONV, sometimes rightfully so, many times wrongly so. PONV is a multifactorial issue involving many physiological and biological mechanisms. As the trend towards ambulatory surgery increases, PONV continues to pose serious challenges for anesthesia providers because the potential cost savings of performing surgeries on an ambulatory basis may be negated by unanticipated hospital admission. Although PONV may be unavoidable in some patients for reasons we do not fully understand, there are risk factors that can be identified. As anesthesiologists it is essential for us to understand the mechanisms involved in nausea and vomiting and the available perioperative treatment options. We must do whatever we can to prevent and treat PONV and improve patient outcome for both medical and economic reasons.