Continuous monitoring of PbrO2 in patients with severe head injury

The first Chapter is an introduction to neurotraumatology. The incidence of severe head injury, and its financial burden to society is described. General information is provided on the currently used monitoring modalities in patients with severe head injury. Finally a description is given of the polarographic monitoring method for measuring oxygen tension in brain tissue (PbrO2) used in our studies. The study questions are specified focussing on clinical applicability of PbrO2 measurements in TBI and interpretation of findings. In Chapter 2 preliminary experience with brain tissue PO2 (PbrO2) monitoring in a group of 22 patients with a severe head injury is described. PbrO2 was measured with a polarographic microcatheter. For introduction of the catheter a specially devised intracranial bolt was used. Measurements started as soon as possible after the injury and the study protocol specified an observation period of a maximum of 120 hours post trauma. The rationale for this time period was that during the initial period after trauma low Cerebral Blood Flow (CBF) values have been reported with Xe CT studies, and that vasospasm mostly occurs before day 5 after injury. Both potential ischemic phenomena are covered by the observation period chosen. During the observation period two provocation tests were included in the study protocol performed on a dayly basis. Firstly, an O2 provocation test, by increasing the fraction of inspired oxygen stepwise to 1.0, and secondly a carbon dioxide reactivity test performed by increasing the respiratory minute volume of the patient by 20%. The observation period was preliminary terminated by early death or if clinical improvement of the patient occurred to an extent that ICP monitoring was no longer considered necessary. PbrO2 monitoring was started on average 7.0 hours after trauma with a mean duration of 74.3 hours. The chapter provides an extensive description of all phenomena observed. No complications were seen related to the PbrO2 catheter. The catheters showed a zero display error of 1.2 ± 0.8 mmHg and a sensitivity drift of 9.7 ± 5.3% after the measurement period. The first approach to analyse the PbrO2 value was to average all PO2 values according to the time after injury. Using this method of analysis we observed low average values during the initial 24 hours after injury, increasing toward a peak value during the second 24 hours reaching a plateau value after 36-48 hours after injury. Beyond this time period mean PbrO2 showed no further changes

Is there a future for ovulation induction in the current era of assisted reproduction?

The clinical use of medical induction of ovulation in normogonadotrophic anovulatory women (WHO II), including polycystic ovary syndrome, is increasingly questioned. However, we believe that this treatment modality still represents a highly effective means of fertility treatment in women with low pregnancy chances without intervention. A conventional treatment algorithm involving clomiphene citrate (CC) followed by FSH induction of ovulation may result in a 71% cumulative singleton live birth rate. In attempts to improve treatment outcome further and reduce complication rates, new compounds such as insulin-sensitizing agents or aromatase inhibitors are currently used increasingly. Approaches such as patient selection for different treatment modalities on the basis of initial screening characteristics and alternative protocols for FSH ovulation induction may also be proposed to render treatment algorithms more patient tailored and therefore improve overall outcomes. More research is needed in this area, rather than referring these patients to assisted reproduction prematurely. This may lead to a more individually tailored approach for ovulation induction in a given patient, resulting in a further improvement of the balance between chances for success versus complications

Urinary follicle-stimulating hormone for normogonadotropic clomiphene-resistant anovulatory infertility: prospective, randomized comparison between low dose step-up and step-down dose regimens

A low dose step-up and step-down regimen for induction of ovulation using urinary FSH was compared in a prospective randomized fashion in 37 normogonadotropic clomiphene-resistant oligo- or amenorrheic infertile women. The objectives was to assess potential differences in duration of treatment, ovarian stimulation (serum FSH levels), and response [serum estradiol (E2) levels and number and size of follicles]. Monitoring (blood sampling and transvaginal sonography) took place on the day of initiation of treatment, the first day of ovarian response as assessed by ultrasound (i.e. the first day a follicle > or = 10 mm could be recognized), the day of hCG administration to induce ovulation, and 3 days thereafter. The median duration of treatment in the low dose step-up group was 18 (range, 7-41) days compared to 9 (range, 4-16) days in the step-down group (P = 0.003), and the total numbers of ampules administered were 20 (range, 7-69) and 14 (range, 7-33), respectively (P = NS). Serum FSH levels from the first day of sonographic ovarian response until the administration of hCG were constant (median increase, 2%/day) in patients receiving the low dose step-up protocol, but showed a decrease (median, 5%/day) in step-down cycles (P < 0.001). Monofollicular growth, defined as not more than one follicle 16 mm or larger on the day of hCG administration, was observed in 56% of low dose step-up and 88% of step-down cycles (P = 0.04). The percentage of patients with normal range periovulatory E2 serum levels (500-1500 pmol/L) was 33% in the low dose step-up group vs. 71% in the step-down group (P = 0.03). We conclude that a step-down protocol for gonadotropin induction of ovulation exhibits a more physiological, late follicular phase FSH serum profile than a low dose step-up protocol. This results in a shorter duration of treatment, a greater number of monofollicular cycles, and more cycles with periovulatory E2 levels within the normal range in the step-down protocol

Agonistic anti-TIGIT treatment inhibits T cell responses in LDLr deficient mice without affecting atherosclerotic lesion development

OBJECTIVE: Co-stimulatory and co-inhibitory molecules are mainly expressed on T cells and antigen presenting cells and strongly orchestrate adaptive immune responses. Whereas co-stimulatory molecules enhance immune responses, signaling via co-inhibitory molecules dampens the immune system, thereby showing great therapeutic potential to prevent cardiovascular diseases. Signaling via co-inhibitory T cell immunoglobulin and ITIM domain (TIGIT) directly inhibits T cell activation and proliferation, and therefore represents a novel therapeutic candidate to specifically dampen pro-atherogenic T cell reactivity. In the present study, we used an agonistic anti-TIGIT antibody to determine the effect of excessive TIGIT-signaling on atherosclerosis. METHODS AND RESULTS: TIGIT was upregulated on CD4(+) T cells isolated from mice fed a Western-type diet in comparison with mice fed a chow diet. Agonistic anti-TIGIT suppressed T cell activation and proliferation both in vitro and in vivo. However, agonistic anti-TIGIT treatment of LDLr(-/-) mice fed a Western-type diet for 4 or 8 weeks did not affect atherosclerotic lesion development in comparison with PBS and Armenian Hamster IgG treatment. Furthermore, elevated percentages of dendritic cells were observed in the blood and spleen of agonistic anti-TIGIT-treated mice. Additionally, these cells showed an increased activation status but decreased IL-10 production. CONCLUSIONS: Despite the inhibition of splenic T cell responses, agonistic anti-TIGIT treatment does not affect initial atherosclerosis development, possibly due to increased activity of dendritic cells

Опыт применения криохирургии в гинекологии

Приведены результаты применения низких температур для лечения ряда гинекологических заболеваний и обоснована необходимость широкого внедрения криогенного метода лечения в клиническую практику.The results of low temperature application in treatment of a number of gynecological diseases are presented, the necessity of wide introduction of cryogenic treatment into clinical practice is substantiated

Implementation of a mobile 0.15-T intraoperative MR system in pediatric neuro-oncological surgery: feasibility and correlation with early postoperative high-field strength MRI

INTRODUCTION: We analyze our preliminary experience using the PoleStar N20 mobile intraoperative MR (iMR) system as an adjunct for pediatric brain tumor resection. METHODS: We analyzed 11 resections in nine children between 1 month and 17 years old. After resection, we acquired iMR scans to detect residual tumor and update neuronavigation. We compared final iMR interpretation by the neurosurgeon with early postoperative MR interpretation by a neuroradiologist. RESULTS: Patient positioning was straightforward, and image quality (T1 7-min 4-mm sequences) sufficient in all cases. In five cases, contrast enhancement suspect for residual tumor was noted on initial postresection iMR images. In one case, a slight discrepancy with postoperative imaging after 3 months was no longer visible after 1 year. No serious perioperative adverse events related to the PoleStar N20 were encountered, except for transient shoulder pain in two. CONCLUSIONS: Using the PoleStar N20 iMR system is technically feasible and safe for both supra- and infratentorial tumor resections in children of all ages. Their small head and shoulders favor positioning in the magnet bore and allow the field of view to cover more than the area of primary interest, e.g., the ventricles in an infratentorial case. Standard surgical equipment may be used without significant limitations. In this series, the use of iMR leads to an increased extent of tumor resection in 45 % of cases. Correlation between iMR and early postoperative MR is excellent, provided image quality is optimal and interpretation is carefully done by someone sufficiently familiar with the system

Cigarette Smoking and Effects on Hormone Function in Premenopausal Women

Cigarette smoke contains compounds that are suspected to cause reproductive damage and possibly affect hormone activity; therefore, we examined hormone metabolite patterns in relation to validated smoking status. We previously conducted a prospective study of women of reproductive age (n = 403) recruited from a large health maintenance organization, who collected urine daily during an average of three to four menstrual cycles. Data on covariates and daily smoking habits were obtained from a baseline interview and daily diary, and smoking status was validated by cotinine assay. Urinary metabolite levels of estrogen and progesterone were measured daily throughout the cycles. For the present study, we measured urinary levels of the pituitary hormone follicle-stimulating hormone (FSH) in a subset of about 300 menstrual cycles, selected by smoking status, with the time of transition between two cycles being of primary interest. Compared with nonsmokers, moderate to heavy smokers (≥ 10 cigarettes/day) had baseline levels (e.g., early follicular phase) of both steroid metabolites that were 25–35% higher, and heavy smokers (≥ 20 cigarettes/day) had lower luteal-phase progesterone metabolite levels. The mean daily urinary FSH levels around the cycle transition were increased at least 30–35% with moderate smoking, even after adjustment. These patterns suggest that chemicals in tobacco smoke alter endocrine function, perhaps at the level of the ovary, which in turn effects release of the pituitary hormones. This endocrine disruption likely contributes to the reported associations of smoking with adverse reproductive outcomes, including menstrual dysfunction, infertility, and earlier menopause