Clinical and genetic determinants of vitamin D receptor expression in cutaneous melanoma patients

Decrease of vitamin D receptor (VDR) expression is observed in melanocytic naevi and melanoma compared to normal skin. Little is known about factors influencing VDR expression in cutaneous melanoma (CM). We investigated the correlation of VDR expression in CM with 25-hydroxy vitamin D (25OHD) levels, demographic/clinical parameters, genetic variants of VDR and pathology of the primary tumor. Demographic/clinical parameters were recorded in 407 prospectively recruited CM patients of a multi-center controlled study (ViDMe trial). We determined VDR expression both in the nucleus and in the cytoplasm by semi-quantitative assessment in CM tissue using histochemistry in 279 patients, expressed in percentages and histoscore (H-score). Genomic DNA from 332 patients was extracted to genotype thirteen VDR single nucleotide polymorphisms (SNPs) using TaqMan. VDR expression in CM tissue from 279 patients was correlated with clinical/demographic parameters and 25OHD levels (univariable and multivariable analysis), VDR SNPs (univariable analysis) and pathology parameters of primary CM tissue (univariable analysis). Cytoplasmic VDR expression was increased in patients who stated to have a high sun exposure during their life compared to patients with low sun exposure (p H-score,univariable : 0.001, p H-score,multivariable : 0.004). The A allele of the genetic VDR polymorphism Fok1 was associated with a higher expression of the VDR in the cytoplasm (p cytoplasmic, univariable : 0.001 and p H-score, univariable : 0.02). In the primary tumor, presence of mitosis (p nucleus,%, univariable : 0.002) and perineural invasion (p nucleus,%,univariable : 0.03) were significantly associated with low nuclear VDR expression. ClinicalTrials.gov Identifier: NCT01748448.

STREAM-2: Half-Dose Tenecteplase or Primary Percutaneous Coronary Intervention in Older Patients With ST-Segment-Elevation Myocardial Infarction: A Randomized, Open-Label Trial

BACKGROUND

ST-segment-elevation myocardial infarction (STEMI) guidelines recommend pharmaco-invasive treatment if timely primary percutaneous coronary intervention (PCI) is unavailable. Full-dose tenecteplase is associated with an increased risk of intracranial hemorrhage in older patients. Whether pharmaco-invasive treatment with half-dose tenecteplase is effective and safe in older patients with STEMI is unknown.

METHODS

STREAM-2 (Strategic Reperfusion in Elderly Patients Early After Myocardial Infarction) was an investigator-initiated, open-label, randomized, multicenter study. Patients ≥60 years of age with ≥2 mm ST-segment elevation in 2 contiguous leads, unable to undergo primary PCI within 1 hour, were randomly assigned (2:1) to half-dose tenecteplase followed by coronary angiography and PCI (if indicated) 6 to 24 hours after randomization, or to primary PCI. Efficacy end points of primary interest were ST resolution and the 30-day composite of death, shock, heart failure, or reinfarction. Safety assessments included stroke and nonintracranial bleeding.

RESULTS

Patients were assigned to pharmaco-invasive treatment (n=401) or primary PCI (n=203). Median times from randomization to tenecteplase or sheath insertion were 10 and 81 minutes, respectively. After last angiography, 85.2% of patients undergoing pharmaco-invasive treatment and 78.4% of patients undergoing primary PCI had ≥50% resolution of ST-segment elevation; their residual median sums of ST deviations were 4.5 versus 5.5 mm, respectively. Thrombolysis In Myocardial Infarction flow grade 3 at last angiography was ≈87% in both groups. The composite clinical end point occurred in 12.8% (51/400) of patients undergoing pharmaco-invasive treatment and 13.3% (27/203) of patients undergoing primary PCI (relative risk, 0.96 [95% CI, 0.62-1.48]). Six intracranial hemorrhages occurred in the pharmaco-invasive arm (1.5%): 3 were protocol violations (excess anticoagulation in 2 and uncontrolled hypertension in 1). No intracranial bleeding occurred in the primary PCI arm. The incidence of major nonintracranial bleeding was low in both groups (<1.5%).

CONCLUSIONS

Halving the dose of tenecteplase in a pharmaco-invasive strategy in this early-presenting, older STEMI population was associated with electrocardiographic changes that were at least comparable to those after primary PCI. Similar clinical efficacy and angiographic end points occurred in both treatment groups. The risk of intracranial hemorrhage was higher with half-dose tenecteplase than with primary PCI. If timely PCI is unavailable, this pharmaco-invasive strategy is a reasonable alternative, provided that contraindications to fibrinolysis are observed and excess anticoagulation is avoided.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02777580.

Determinants of 25-hydroxyvitamin D Status in a Cutaneous Melanoma Population

Vitamin D status is influenced by well-known determinants, but factors associated with low 25-hydroxyvitamin D levels in the cutaneous melanoma population are not well defined. The aim of this study was to confirm the well-known determinants and to assess new determinants for 25-hydroxyvitamin D levels in a cutaneous melanoma population. In a prospectively included cohort of 387 patients with cutaneous melanoma the association of 25-hydroxyvitamin D levels with sex, age, body mass index, time of blood withdrawal, Fitzpatrick phototype, vitamin D supplementation, score for intensity of lifetime sun exposure, smoking, education level, hair and skin colour, eye colour, total number of benign naevi, freckles and parameters of chronic sun damage was investigated. In addition, 25-hydroxyvitamin D levels were correlated with pathological parameters of the primary tumour and melanoma stage (8th edition of the American Joint Committee on Cancer (AJCC). Univariate and multivariate logistic regressions were performed using R software. The following factors had a significant effect on vitamin D status: body mass index, seasonal time of blood sampling, vitamin D supplementation, and a subtype of skin, and hair colour.

A randomized, multicentre, open-label phase II proof-of-concept trial investigating the clinical efficacy and safety of the addition of convalescent plasma to the standard of care in patients hospitalized with COVID-19: the Donated Antibodies Working against nCoV (DAWn-Plasma) trial

BACKGROUND

The COVID-19 pandemic has imposed an enormous burden on health care systems around the world. In the past, the administration of convalescent plasma of patients having recovered from SARS and severe influenza to patients actively having the disease showed promising effects on mortality and appeared safe. Whether or not this also holds true for the novel SARS-CoV-2 virus is currently unknown.

METHODS

DAWn-Plasma is a multicentre nation-wide, randomized, open-label, phase II proof-of-concept clinical trial, evaluating the clinical efficacy and safety of the addition of convalescent plasma to the standard of care in patients hospitalized with COVID-19 in Belgium. Patients hospitalized with a confirmed diagnosis of COVID-19 are eligible when they are symptomatic (i.e. clinical or radiological signs) and have been diagnosed with COVID-19 in the 72 h before study inclusion through a PCR (nasal/nasopharyngeal swab or bronchoalveolar lavage) or a chest-CT scan showing features compatible with COVID-19 in the absence of an alternative diagnosis. Patients are randomized in a 2:1 ratio to either standard of care and convalescent plasma (active treatment group) or standard of care only. The active treatment group receives 2 units of 200 to 250 mL of convalescent plasma within 12 h after randomization, with a second administration of 2 units 24 to 36 h after ending the first administration. The trial aims to include 483 patients and will recruit from 25 centres across Belgium. The primary endpoint is the proportion of patients that require mechanical ventilation or have died at day 15. The main secondary endpoints are clinical status on day 15 and day 30 after randomization, as defined by the WHO Progression 10-point ordinal scale, and safety of the administration of convalescent plasma.

DISCUSSION

This trial will either provide support or discourage the use of convalescent plasma as an early intervention for the treatment of hospitalized patients with COVID-19 infection.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04429854 . Registered on 12 June 2020 - Retrospectively registered.

Nitric oxide for inhalation in ST-elevation myocardial infarction (NOMI): a multicentre, double-blind, randomized controlled trial

Aims

Inhalation of nitric oxide (iNO) during myocardial ischaemia and after reperfusion confers cardioprotection in preclinical studies via enhanced cyclic guanosine monophosphate (cGMP) signalling. We tested whether iNO reduces reperfusion injury in patients with ST-elevation myocardial infarction (STEMI; NCT01398384).

Methods and results

We randomized in a double-blind, placebo-controlled study 250 STEMI patients to inhale oxygen with (iNO) or without (CON) 80 parts-per-million NO for 4 h following percutaneous revascularization. Primary efficacy endpoint was infarct size as a fraction of left ventricular (LV) size (IS/LVmass), assessed by delayed enhancement contrast magnetic resonance imaging (MRI). Pre-specified subgroup analysis included thrombolysis-in-myocardial-infarction flow in the infarct-related artery, troponin T levels on admission, duration of symptoms, location of culprit lesion, and intra-arterial nitroglycerine (NTG) use. Secondary efficacy endpoints included IS relative to risk area (IS/AAR), myocardial salvage index, LV functional recovery, and clinical events at 4 and 12 months. In the overall population, IS/LVmass at 48-72 h was 18.0 ± 13.4% in iNO (n = 109) and 19.4 ± 15.4% in CON [n = 116, effect size -1.524%, 95% confidence interval (95% CI) -5.28, 2.24; P = 0.427]. Subgroup analysis indicated consistency across clinical confounders of IS but significant treatment interaction with NTG (P = 0.0093) resulting in smaller IS/LVmass after iNO in NTG-naïve patients (n = 140, P < 0.05). The secondary endpoint IS/AAR was 53 ± 26% with iNO vs. 60 ± 26% in CON (effect size -6.8%, 95% CI -14.8, 1.3, P = 0.09) corresponding to a myocardial salvage index of 47 ± 26% vs. 40 ± 26%, respectively, P = 0.09. Cine-MRI showed similar LV volumes at 48-72 h, with a tendency towards smaller increases in end-systolic and end-diastolic volumes at 4 months in iNO (P = 0.048 and P = 0.06, respectively, n = 197). Inhalation of nitric oxide was safe and significantly increased cGMP plasma levels during 4 h reperfusion. The Kaplan-Meier analysis for the composite of death, recurrent ischaemia, stroke, or rehospitalizations showed a tendency toward lower event rates with iNO at 4 months and 1 year (log-rank test P = 0.10 and P = 0.06, respectively).

Conclusions

Inhalation of NO at 80 ppm for 4 h in STEMI was safe but did not reduce infarct size relative to absolute LVmass at 48-72h. The observed functional recovery and clinical event rates at follow-up and possible interaction with nitroglycerine warrant further studies of iNO in STEMI.

Intensive recreational athletes in the prospective multinational ICD Sports Safety Registry: Results from the European cohort

Background

In the ICD Sports Safety Registry, death, arrhythmia- or shock-related physical injury did not occur in athletes who continue competitive sports after implantable cardioverter-defibrillator (ICD) implantation. However, data from non-competitive ICD recipients is lacking. This report describes arrhythmic events and lead performance in intensive recreational athletes with ICDs enrolled in the European recreational arm of the Registry, and compares their outcome with those of the competitive athletes in the Registry.

Methods

The Registry recruited 317 competitive athletes ≥ 18 years old, receiving an ICD for primary or secondary prevention (234 US; 83 non-US). In Europe, Israel and Australia only, an additional cohort of 80 ‘auto-competitive’ recreational athletes was also included, engaged in intense physical activity on a regular basis (≥2×/week and/or ≥ 2 h/week) with the explicit aim to improve their physical performance limits. Athletes were followed for a median of 44 and 49 months, respectively. ICD shock data and clinical outcomes were adjudicated by three electrophysiologists.

Results

Compared with competitive athletes, recreational athletes were older (median 44 vs. 37 years; p = 0.0004), more frequently men (79% vs. 68%; p = 0.06), with less idiopathic ventricular fibrillation or catecholaminergic polymorphic ventricular tachycardia (1.3% vs. 15.4%), less congenital heart disease (1.3% vs. 6.9%) and more arrhythmogenic right ventricular cardiomyopathy (23.8% vs. 13.6%) ( p < 0.001). They more often had a prophylactic ICD implant (51.4% vs. 26.9%; p < 0.0001) or were given a beta-blocker (95% vs. 65%; p < 0.0001). Left ventricular ejection fraction, ICD rate cut-off and time from implant were similar. Recreational athletes performed fewer hours of sports per week (median 4.5 vs. 6 h; p = 0.0004) and fewer participated in sports with burst-performances ( vs. endurance) as their main sports: 4% vs. 65% ( p < 0.0001). None of the athletes in either group died, required external resuscitation or was injured due to arrhythmia or shock. Freedom from definite or probable lead malfunction was similar (5-year 97% vs. 96%; 10-year 93% vs. 91%). Recreational athletes received fewer total shocks (13.8% vs. 26.5%, p = 0.01) due to fewer inappropriate shocks (2.5% vs. 12%; p = 0.01). The proportion receiving appropriate shocks was similar (12.5% vs. 15.5%, p = 0.51). Recreational athletes received fewer total (6.3% vs. 20.2%; p = 0.003), appropriate (3.8% vs. 11.4%; p = 0.06) and inappropriate (2.5% vs. 9.5%; p = 0.04) shocks during physical activity. Ventricular tachycardia/fibrillation storms during physical activity occurred in 0/80 recreational vs. 7/317 competitive athletes. Appropriate shocks during physical activity were related to underlying disease ( p = 0.004) and competitive versus recreational sports ( p = 0.004), but there was no relation with age, gender, type of indication, beta-blocker use or burst/endurance sports. The proportion of athletes who stopped sports due to shocks was similar (3.8% vs. 7.5%, p = 0.32).

Conclusions

Participants in recreational sports had less frequent appropriate and inappropriate shocks during physical activity than participants in competitive sports. Shocks did not cause death or injury. Recreational athletes with ICDs can engage in sports without severe adverse outcomes unless other reasons preclude continuation.

Vitamin D supplementation in cutaneous malignant melanoma outcome (ViDMe): a randomized controlled trial

BACKGROUND

Previous studies have investigated the protective effect of vitamin D serum levels, at diagnosis and during the follow-up period after treatment, on melanoma outcome. In the present study we assess whether vitamin D supplementation, in the follow-up period after diagnosis and surgical resection of the primary tumor, has a protective effect on relapse of cutaneous malignant melanoma and whether this protective effect correlates with vitamin D levels in serum and Vitamin D Receptor immunoreactivity in the primary tumor.

METHODS/DESIGN

This study is a multicenter randomized double blind placebo- controlled phase III trial. Patients between the age of 18 and 80 years diagnosed and treated surgically for a melanoma stage IB-III are eligible for randomization in a 1:1 ratio to active treatment or placebo. The study drug is taken each month and consists of either 100,000 International Unit cholecalciferol or arachidis oleum raffinatum used as a placebo. The primary endpoint is relapse free survival. The secondary endpoints are 25 hydroxyvitamin D3 serum levels at diagnosis and at 6 month intervals, melanoma subtype, melanoma site and stage of melanoma at diagnosis according to the 2009 American Joint Committee on Cancer melanoma staging and classification. At randomization a bloodsample is taken for DNA analysis. The study is approved by the local Ethics Committees.

DISCUSSION

If we can confirm our hypothesis that vitamin D supplementation after removal of the tumor has a protective effect on relapse of cutaneous malignant melanoma we may reduce the burden of CMM at several levels. Patients, diagnosed with melanoma may have a better clinical outcome and improved quality of life. There will be a decrease in health care costs related to treatment of metastatic disease and there will be a decrease in loss of professional years, which will markedly reduce the economic burden of the disease.

TRIAL REGISTRATION

Clinical Trial.gov, NCT01748448 , 05/12/2012.

Fibrinolysis or primary PCI in ST-segment elevation myocardial infarction

BACKGROUND

It is not known whether prehospital fibrinolysis, coupled with timely coronary angiography, provides a clinical outcome similar to that with primary percutaneous coronary intervention (PCI) early after acute ST-segment elevation myocardial infarction (STEMI).

METHODS

Among 1892 patients with STEMI who presented within 3 hours after symptom onset and who were unable to undergo primary PCI within 1 hour, patients were randomly assigned to undergo either primary PCI or fibrinolytic therapy with bolus tenecteplase (amended to half dose in patients ≥75 years of age), clopidogrel, and enoxaparin before transport to a PCI-capable hospital. Emergency coronary angiography was performed if fibrinolysis failed; otherwise, angiography was performed 6 to 24 hours after randomization. The primary end point was a composite of death, shock, congestive heart failure, or reinfarction up to 30 days.

RESULTS

The primary end point occurred in 116 of 939 patients (12.4%) in the fibrinolysis group and in 135 of 943 patients (14.3%) in the primary PCI group (relative risk in the fibrinolysis group, 0.86; 95% confidence interval, 0.68 to 1.09; P=0.21). Emergency angiography was required in 36.3% of patients in the fibrinolysis group, whereas the remainder of patients underwent angiography at a median of 17 hours after randomization. More intracranial hemorrhages occurred in the fibrinolysis group than in the primary PCI group (1.0% vs. 0.2%, P=0.04; after protocol amendment, 0.5% vs. 0.3%, P=0.45). The rates of nonintracranial bleeding were similar in the two groups.

CONCLUSIONS

Prehospital fibrinolysis with timely coronary angiography resulted in effective reperfusion in patients with early STEMI who could not undergo primary PCI within 1 hour after the first medical contact. However, fibrinolysis was associated with a slightly increased risk of intracranial bleeding. (Funded by Boehringer Ingelheim; ClinicalTrials.gov number, NCT00623623.).

Importance of measurements at or after the J-point for evaluation of ST-segment deviation and resolution during treatment for acute myocardial infarction

BACKGROUND

Determination of ST-segment deviation (STdev) and its resolution (STR) by reperfusion strategies have become important tools in the assessment of patients with acute myocardial infarction (AMI). STdev has been measured at different time-points, i.e. at 20-80 ms after the J-point. There are no data comparing STR at different time-points.

METHODS AND RESULTS

STdev was measured using a new computer-assisted workflow. The intraclass correlation coefficients (ICC) for validity and agreement vs. classical manual measurements (n=1020) were both 0.996 (p<0.0001). The reliability indices were 0.991 (95% CI 0.990-0.992) for the manual vs. 0.995 (95% CI 0.995-0.996) for the computer-assisted method, indicating superiority of the latter. 12-lead STdev were determined on ECGs before (baseline) and 180 min after start of thrombolytic therapy, measured both at the J-point (STdev(J)) and 20 ms after the J-point (STdev(J20); n=2400). STdev(J20) was on average 0.01+/-0.03 mV higher than STdev(J) (p<0.0001) with a tendency towards larger differences for higher ST-elevations (p<0.001). Although the average STR calculated from STdev(J20) and STdev(J) was not statistically different in any infarct location group, in 26% of the patients the difference was >10%, and 11% of the patients were classified into another ST-resolution group. Analysing STdev only in the single lead with the highest ST-elevation at baseline (a simplified measurement which may eliminate the confounding effect of ST-depressions) showed an even higher classification discordance (14% of the patients).

CONCLUSIONS

The time-point of STdev measurement is an important variable to be accounted for when evaluating ST resolution data. Uncontrolled extrapolation of classification schemes based on STdev(J20) to other time-points cannot be justified.

Miscalibration and severe complications after diode laser cyclophotocoagulation: two case reports

Because two similar transscleral cyclophotocoagulation diode lasers with identical power & duration settings induced significantly different postoperative inflammation, we wanted to compare the real output of both lasers. Using a Power/Energy Meter (Fieldmaster) we compared the output of the two lasers (the Iridis [Quantel Medical] and the Iris Medical [OcuLight SLx]) at different energy levels. At a setting of 600, 1000, 1400, 1700, 2000 and 2500 mW, the measured output for the Iridis and Iris Medical diode laser were respectively 685 and 400 mW, 970 and 650 mW, 1470 and 875 mW, 1700 and 1000 mW, and 1990 compared to 1000 mW. On the average the output of the Iridis laser was correct and the output of the Iris Medical laser was 40% lower than the setting. Overtreatment and severe complications occurred with the Iridis laser because the manufacturer recommended using wrong power settings based on the Iris Medical laser, which was undercalibrated. The calibration of cyclophotocoagulation diode lasers should be performed prior to use when changing to a new device and whenever over- or undertreatment is observed.

ST-deviation reconstruction in missing leads on the 12-lead ECG: applicability in studies on ST-segment resolution during thrombolysis

Quantitative analysis of ST-segment deviations (STdev) and their resolution by treatment (STR; calculated from a combined sum of STdev in multiple leads) are used in trials on reperfusion for myocardial infarction (MI). Unreadable or unavailable electrocardiogram (ECG) leads are a common reason for exclusion, decreasing the statistical power of the trials. We developed mathematical formulas for reconstruction of immeasurable STdev based on STdev from other available leads on the 12-lead ECG. Formulas were deducted from a database of computer-assisted STdev measurements in 2 ECGs (baseline and 180 min after thrombolysis) of 1121 pts. Their accuracy was later evaluated on a second dataset of 377 pts. Acceptable fits could be derived for absent single leads, or for groups of absent limb leads (I-II-III or aVL-aVF). The intraclass correlation coefficient between real and calculated STdev was >or= 0.80 for each (0.77 for V1 in inferior MI). The correlations between STR calculated from original data and from reconstructed STdev were very strong (all intraclass correlation >or=0.97), and discordance in STR subgroup categorization occurred in <or=10% of pts in all but one of the scenarios (I-II-III substituted in 180 min ECG in inferior MI). Scenarios with multiple missing precordial leads however are not substitutable, nor are calculated STdev reliable for STR evaluation in only the lead with highest elevation in baseline. STdev reconstruction formulas can reliably be used in trials where analysis of aggregate STR is an endpoint. Reliable substitution can significantly increase the number of evaluable patients and therefore strengthen the statistical power of these trials.

High viral burden in the presence of major HIV-specific CD8(+) T cell expansions: evidence for impaired CTL effector function

To investigate the effect of HIV-specific CD8(+) T cells on viral plasma load and disease progression, we enumerated HLA-A2-, B8- and B57-restricted CD8(+) T cells directed against several HIV epitopes in a total of 54 patients by the use of tetrameric HLA-peptide complexes. In patients with high CD4(+) T cell numbers, HIV-specific tetramer(+) cells inversely correlated with viral load. Patients with CD4(+) T cell numbers below 400/microl blood, however, carried high viral load despite frequently having high tetramer(+) T cell numbers. This lack of correlation between viral load and tetramer(+) cells did not result from viral escape variants, as in only 4 of 13 patients, low frequencies of viruses with mutated epitopes were observed. In 15 patients we measured CD8(+) T cell antigen responsiveness to HIV peptide stimulation in vitro. FACS analyses showed differential IFN-gamma production of the tetramer(+) cells, and this proportion of IFN-gamma-producing tetramer(+) cells correlated with AIDS-free survival and with T cell maturation to the CD27(-) effector stage. These data show that most HIV-infected patients have sustained HIV-specific T cell expansions but many of these cells seem not to be functional, leaving the patient with high numbers of non-functional virus-specific CD8(+) T cells in the face of high viral burden.

Bilateral cataract and high myopia in a child with trichothiodystrophy: a case report

Trichothiodystrophy refers to a group of autosomal recessive disorders that have in common brittle sulphur-deficient hair (7). The abnormalities are usually obvious at birth and the clinical expression is variable. Ocular abnormalities are common with bilateral cataract being the most frequent one. We report on a four year old boy with trichothiodystrophy (complementation group TTD-A) who presented to us with strabismus, high myopia and bilateral cataract.

A comparison of methods for preoperative discrimination between malignant and benign adnexal masses: the development of a new logistic regression model

OBJECTIVE

The aim of this study was to assess the complementary use of ultrasonographic end points with the level of circulating CA 125 antigen by multivariate logistic regression analysis algorithms to distinguish malignant from benign adnexal masses before operation.

STUDY DESIGN

One hundred ninety-one patients aged 18 to 93 years with overt adnexal masses were examined by transvaginal ultrasonography with color Doppler imaging and 31 variables were recorded. The end points were the histologic classification of the tumor and the areas under the receiver-operator characteristic curves of alternative algorithms.

RESULTS

One hundred forty patients had benign tumors and 51 (26.7%) had malignant tumors: 31 primary invasive tumors (37% International Federation of Gynecology and Obstetrics stage I), 5 tumors of borderline malignancy (100% International Federation of Gynecology and Obstetrics stage I), and 15 tumors were metastatic and invasive. The most useful variables for the logistic regression analysis were the menopausal status, the serum CA 125 level, the presence of >/=1 papillary growth (>3 mm in length), and a color score indicative of tumor vascularity and blood flow. The optimized procedure had a sensitivity of 95.9% and a specificity of 87.1%. The area under the receiver-operator characteristic curve was significantly higher (P <.01) than the corresponding values from the independent use of serum CA 125 levels or indexes of tumor form or vascularity.

CONCLUSION

Regression analysis of a few complementary variables can be used to accurately discriminate between malignant and benign adnexal masses before operation.

Regulation of glycogen breakdown by glycogen level in contracting rat muscle

The interaction of glycogen concentration, insulin and beta-adrenergic stimulation in the regulation of glycogen breakdown was studied in perfused rat muscles. Rats were pre-conditioned to obtain two groups with either normal (N) or 'supercompensated' (SC) muscle glycogen. The next day their hindlimbs were perfused with a medium containing insulin (0, 40 and 100 microU mL(-1)) and/or isoproterenol (0 and 1.5 nmol L(-1)). Contractions were induced by electrical stimulation of the sciatic nerve. Compared with N, glycogen breakdown in white gastrocnemius during contractions was greater in SC at any hormonal combination (P < 0.05). Conversely, in red gastrocnemius (RG) the higher glycogenolytic rate in SC, compared with N, faded as the insulin concentration was raised from 0 to 100 microU mL(-1). However, isoproterenol restored the higher glycogenolytic rate in SC. In any condition, RG glycogen synthase fractional activity was lower (P < 0.05) during contractions in SC than in N. Furthermore, the percentage of phosphorylase a was higher in SC except when muscles were exposed to insulin alone. In conclusion, high initial glycogen concentration in fast-glycolytic muscle causes high glycogenolytic rate during contractions, irrespective of hormonal stimulation. In contrast, due to down-regulation of phosphorylase activity, such a relationship does not exist in insulin-stimulated fast-oxidative muscle.

Shortening of muscle relaxation time after creatine loading

The effect of creatine (Cr) supplementation on muscle isometric torque generation and relaxation was investigated in healthy male volunteers. Maximal torque (Tmax), contraction time (CT) from 0.25 to 0.75 of Tmax, and relaxation time (RT) from 0.75 to 0.25 of Tmax were measured during 12 maximal isometric 3-s elbow flexions interspersed by 10-s rest intervals. Between the pretest and the posttest, subjects ingested Cr monohydrate (4 x 5 g/day; n = 8) or placebo (n = 8) for 5 days. Pretest Tmax, CT, and RT were similar in Cr and placebo groups. Also in the posttest, Tmax and CT were similar between groups. However, posttest RT was decreased consistently by approximately 20% (P < 0.05) in the Cr group from the first to the last of the 12 contractions. In addition, the mean decrease in RT after Cr loading was positively correlated with pretest RT (r = 0.82). It is concluded that Cr loading facilitates the rate of muscle relaxation during brief isometric muscle contractions without affecting torque production.

Phosphocreatine resynthesis is not affected by creatine loading

PURPOSE

Oral creatine supplementation has been shown to improve power output during high intensity intermittent muscle contractions. Facilitated muscle phosphocreatine (PCr) resynthesis, by virtue of elevated intracellular PCr concentration, might contribute to this ergogenic action. Therefore, the effect of creatine loading (C: 25 g X d(-1) for 5 d) on muscle PCr breakdown and resynthesis and muscle performance during high intensity intermittent muscle contractions was investigated.

METHODS

A double-blind randomized cross-over study was performed in young healthy male volunteers (N = 9). 31P-NMR spectroscopy of the m. gastrocnemius and isokinetic dynamometry of knee-extension torque were performed before and after 2 and 5 d of either placebo (P) or C administration.

RESULTS

Compared with P, 2 and 5 d of C increased (P < 0.05) resting muscle PCr concentration by 11% and 16%, respectively. Furthermore, torque production during maximal intermittent knee extensions, including the first bout of contractions, was increased (P < 0.05) by 5-13% by either 2 or 5 d of C. However, compared with P, the rate of PCr breakdown and resynthesis during intermittent isometric contractions of the calf was not significantly affected by C.

CONCLUSION

Creatine loading raises muscle PCr concentration and improves performance during rapid and dynamic intermittent muscle contractions. Creatine loading does not facilitate muscle PCr resynthesis during intermittent isometric muscle contractions.

Experience with fetoscopic cord ligation

OBJECTIVE

In the case of a monochorionic multiple pregnancy with one non-viable fetus who compromises its co-twin, fetoscopic cord ligation may be performed. We describe our fetoscopic cord ligation technique and discuss the efficacy of cord ligation for salvaging the co-twin, based on available data.

STUDY DESIGN

Descriptive case series of four cases and review of the cases published up to 1996.

RESULTS

We performed four successful ligations. Of the 23 reported cases, which include the present series, two ligations failed. Four fetuses died in utero, and 17 were born alive at a mean of 8 weeks following the procedure. Two babies died in the perinatal period, a third after 60 days. Preterm uterine contractions do not seem to be a clinical problem. Preterm prelabour rupture of the membranes (PPROM) complicates about 40% of cases, the majority occurring prior to 32 weeks.

CONCLUSION

Fetoscopic cord ligation is a feasible procedure with a 71% survival rate and a high risk for PPROM.

Tracheoscopic endoluminal plugging using an inflatable device in the fetal lamb model

OBJECTIVE

Intra-uterine tracheal occlusion has been proposed to reverse pulmonary hypoplasia, an important prognostic factor in congenital diaphragmatic hernia. We aimed to evaluate the feasibility and pulmonary effects of tracheoscopic tracheal obstruction with a detachable balloon.

STUDY DESIGN

Fourteen mid-trimester fetuses out of 24 in 13 ewes underwent tracheoscopic balloon obstruction. Ten non-operated fetuses served as controls. Plugging was performed under fiber-tracheoscopy using a detachable balloon. Outcome measures consisted of: total operating time, tracheoscopy time, fetal survival, efficiency of plugging, and pulmonary effects. The Mann-Whitney test and linear regression were used for statistical analysis.

RESULTS

Mean operating time and tracheoscopy time were 65+/-12 and 6.6+/-3.9 min, respectively. One intra-operative death occurred in each group. The post-operative mortality was 2/13 for cases and 2/9 for controls. In all 14 fetuses, the trachea was successfully obstructed. In the 11 treated animals born alive, the lung-to-body-weight ratio was 0.060+/-0.01, while in controls it was 0.031+/-0.01 (P = 0.0001). In a subset of six fetuses obstructed for 14-18 days, mean-terminal-bronchial density was 0.95+/-0.59, compared to 2.06+/-0.80 for controls (P = 0.046).

CONCLUSIONS

Using fetal tracheoscopy, the trachea can successfully be obstructed with an inflatable balloon. Pulmonary hyperplasia is achieved when the obstruction lasts 2 weeks.

Effect of creatine loading on endurance capacity and sprint power in cyclists

The effect of creatine loading on endurance capacity and sprint performance was investigated in elite cyclists according to a double-blind cross-over study design. Subjects (n = 12) underwent on 3 occasions and separated by 5 week wash-out periods, a 2 h 30 min standardized endurance protocol on their own race bicycle, which was mounted on an electromagnetically braked roller-system, whereupon they cycled to exhaustion at their predetermined 4 mmol lactate threshold. Immediately thereafter they performed 5 maximal 10 second sprints, separated by 2 min recovery intervals, on a Monark bicycle ergometer at 6 kg resistance on the flywheel. Before the exercise test, subjects were either creatine loaded (C: 25 g creatine monohydrate/day, 5 days) or were creatine loaded plus ingested creatine during the exercise test (CC: 5 g/h), or received placebo (P). Compared with P, C but not CC increased (p<0.05) peak and mean sprint power output by 8-9% for all 5 sprints. Endurance time to exhaustion was not affected by either C or CC. It is concluded that creatine loading improves intermittent sprint capacity at the end of endurance exercise to fatigue. This ergogenic action is counteracted by high dose creatine intake during exercise.

Fetal cardiac tamponade due to an intrapericardial teratoma

A case of an intrapericardial tumor diagnosed in utero at 26 weeks of gestation is presented. The prenatal echocardiographic follow-up of an incipient hydrops fetalis determined the management and the emergency surgical treatment. Histologically, the tumor appeared to be a benign teratoma, grade I. In the postoperative period an unexpected mediastinal tumor was found and removed later. This tumor also appeared to be a benign teratoma, grade 0. Both teratomas were independent and therefore primary.

Fetal membrane closure techniques after hysteroamniotomy in the midgestational rabbit model

OBJECTIVE

We studied closure techniques for amniotic access in midgestational rabbits.

STUDY DESIGN

Twenty-eight rabbits with a total of 313 amniotic sacs were used for this study. In each animal a 1 cm hysteroamniotomy was made in two amniotic sacs at 22 days' gestation (term = 32). For 12 amniotic sacs (group 1) only the myometrium was closed by microsurgical suturing. In group 2 (n = 12), sutures included myometrium and membranes. In group 3 (n = 8), a collagen plug was placed, and in group 4 (n = 12) fibrin glue was used. Twelve sacs were left unclosed (positive controls) and the unmanipulated 257 sacs were negative controls. Eight days later (gestational age 30 days) amniotic sacs were evaluated for the presence of amniotic fluid, membrane integrity, and fetal weight and survival. Statistics were done with two-tailed Fisher's exact test and one-way analysis of variance.

RESULTS

Membrane integrity (p = 0.0036) and amniotic fluid (p = 0.047) were best restored after myometrial closure. Fetal weight and survival rate were not affected by different closure techniques.

CONCLUSION

In this model primary closure of the myometrium only yielded best results.

Alternative technique for Nd: YAG laser coagulation in twin-to-twin transfusion syndrome with anterior placenta

Nd: YAG laser coagulation is used to treat severe twin-to-twin transfusion syndrome (TTS). Success of the technique depends on visualization of the placenta, the fetal membranes and the targeted vessels, as well as obtaining an optimal inclination angle for laser coagulation. In the rare case of an extensive anterior placenta, it may be difficult to achieve these conditions using the percutaneous approach. Here, we propose an alternative to the percutaneous procedure. Modifications involve an open access and the use of a flexible cannula and bent scope. An extraplacental area, usually at the fundus, is identified by B-mode and color Doppler imaging. A mini-laparotomy is made under general anesthesia. The viscera are retracted and the cannula is inserted under direct view and ultrasound control by the Seldinger technique. The curved fiberscope is passed through the flexible cannula, allowing adequate inspection of the placenta, and target vessels can be coagulated at an angle close to 90 degrees. After the procedure, the uterus is closed primarily to prevent postoperative leakage of amniotic fluid or hemorrhage. This technique has been successfully used in six patients with TTS and a completely anterior placenta, with a gestational age between 18.5 and 22.0 weeks. In all patients, the amniotic cavity was accessed without hemorrhage. The outcomes are similar to those published previously for laser coagulation. The mean interval from intervention until delivery was 10.5 weeks. All 12 fetuses were live born but four died from complications of extreme prematurity. No maternal complications occurred.

Polyhydramnios as a prenatal symptom of the digeorge/velo-cardio-facial syndrome

Prenatal diagnosis of the DiGeorge/velo-cardio-facial syndrome has become possible since it was recognized that this syndrome is caused by a submicroscopic deletion in chromosome 22q11. In a sporadic patient presenting a conotruncal heart defect and polyhydramnios, the del 22q11 was made prenatally by fluorescence in situ hybridization (FISH) after amniocentesis. Seven additional patients with a del 22q11 were identified, who presented during pregnancy with polyhydramnios. In one of them, unilateral hydronephrosis was present. These findings further add to a growing list of clinical presentations of a del 22q11 and suggest that in patients with polyhydramnios and a conotruncal heart defect or uropathy, fetal karyotyping should be complemented by FISH for a del 22q11.

Prenatal diagnosis of a terminal short arm deletion of chromosome 8 in a fetus with an atrioventricular septal defect

We report the prenatal diagnosis at 30 weeks of gestation of a del(8)(p21.3-->pter) in a growth-retarded fetus with an unbalanced atrioventricular septal defect (AVSD) and a hypoplastic right ventricle. This observation further confirms the association of AVSD with terminal deletions of chromosome 8p. Terminal deletions of chromosome 8p are more frequent than previously thought, but small terminal deletions can easily be overlooked. This observation illustrates that when an AVSD is diagnosed prenatally, special attention should be paid to distal chromosome 8p.

Long-term creatine intake is beneficial to muscle performance during resistance training

The effects of oral creatine supplementation on muscle phosphocreatine (PCr) concentration, muscle strength, and body composition were investigated in young female volunteers (n = 19) during 10 wk of resistance training (3 h/wk). Compared with placebo, 4 days of high-dose creatine intake (20 g/day) increased (P < 0.05) muscle PCr concentration by 6%. Thereafter, this increase was maintained during 10 wk of training associated with low-dose creatine intake (5 g/day). Compared with placebo, maximal strength of the muscle groups trained, maximal intermittent exercise capacity of the arm flexors, and fat-free mass were increased 20-25, 10-25, and 60% more (P < 0. 05), respectively, during creatine supplementation. Muscle PCr and strength, intermittent exercise capacity, and fat-free mass subsequently remained at a higher level in the creatine group than in the placebo group during 10 wk of detraining while low-dose creatine was continued. Finally, on cessation of creatine intake, muscle PCr in the creatine group returned to normal within 4 wk. It is concluded that long-term creatine supplementation enhances the progress of muscle strength during resistance training in sedentary females.

Intrauterine tracheal obstruction, a new treatment for congenital diaphragmatic hernia, decreases amniotic fluid sodium and chloride concentrations in the fetal lamb

OBJECTIVE

To evaluate the effect of fetal tracheal occlusion on sodium and chloride concentrations in amniotic and tracheal fluid.

SUMMARY BACKGROUND DATA

Intrauterine tracheal occlusion has been proposed to reverse pulmonary hypoplasia, an important prognostic factor in congenital diaphragmatic hernia. In early human trials, technical failure of the obstructive device has been reported.

METHODS

Eight fetal lambs (gestational age = 95 days) were subjected to fetal tracheoscopy, and amniotic and tracheal fluid samples were taken. In multiple pregnancies (n = 6), amniotic fluid was also sampled from the contralateral amniotic sac and used as a control. Subsequently, endotracheal obstruction, using a detachable balloon, was performed. After 14 days, all fetuses were delivered, and sodium and chloride concentrations in amniotic and tracheal fluid were measured again. Statistical analysis was done using a two-tailed Student's t test, paired or unpaired as appropriate.

RESULTS

In controls, between 95 and 109 days gestational age, no significant changes occurred in sodium or chloride concentrations in amniotic or tracheal fluid. After 2 weeks of tracheal obstruction, however, chloride and sodium concentrations in amniotic fluid decreased (chloride = 76.7 mEq/L vs. 107.6 mEq/L, p = 0.0003; sodium = 109.6 mEq/L vs. 125.9 +/- 5.2 mEq/L, p = 0.019). A concomitant increase in chloride and sodium concentration was observed in tracheal fluid (chloride = 145.4 mEq/L vs. 130.0 mEq/L, p = 0.047; sodium = 153.1 mEq/L vs. 142.9 mEq/L, p = 0.051). When comparing groups at 109 days, chloride and sodium concentrations in amniotic fluid were markedly lower in the treated group versus controls (p = 0.0004 and p = 0.05 for chloride and sodium, respectively).

CONCLUSION

Complete tracheal occlusion in ovine fetuses results in a significant decrease of amniotic fluid sodium and chloride concentrations.

Operative fetoscopy: new perspective in fetal therapy?

In a limited number of conditions in utero surgery may be life-saving, such as some cases of congenital diaphragmatic hernia, cystic adenomatoid malformation of the lung, sacrococcygeal teratoma and lower urinary tract obstruction. Postoperative premature labour and its extreme invasiveness have been major drawbacks for open fetal surgery. More recently the merger of fetoscopy and advanced video-endoscopic surgery has been the basis of the concept of endoscopic fetal surgery. In order to evaluate the opportunities of 'fetendo' surgery, animal models have been developed to test the safety of the endoscopic approach, and the feasibility of surgical manipulations on the fetus. In the non-human primate, a lesser invasiveness of endoscopy over open surgical approach was demonstrated, by a significant decrease in uterine activity in comparison with hysterotomy. The main application of fetoscopy today is the surgical treatment of complicated or abnormal monochorionic twin gestations. Fetoscopic laser coagulation of chorionic plate vessels is suggested as a causal therapy for severe feto-fetal transfusion syndrome. Survival rates are around 55 per cent with an incidence of five per cent of neurological morbidity. Fetoscopic cord ligation is associated with a 66 per cent survival rate, but unfortunately also with a risk of 30 per cent for PPROM prior to 32 weeks. Although still in its early experimental phase, endoscopy seems to offer new hope for surgical fetal therapy. Though conceptually very tempting, the development of endoscopic fetal surgery should follow the formal guidelines, as earlier formulated for open surgery by the International Fetal Medicine and Surgery Society. The prospective registration of worldwide experience is advocated and a randomized trial of laser therapy versus amniodrainage is announced.

Tracheoscopic endotracheal occlusion in the ovine model: technique and pulmonary effects

BACKGROUND/PURPOSE

The purpose of this study was to assess the tracheoscopic placement of a detachable balloon to obstruct the trachea in the fetal lamb model and to study the pulmonary effects 2 weeks later.

METHODS

Thirteen pregnant ewes carrying 27 fetuses were used in this trial. Thirteen fetuses underwent endotracheal plugging at a mean gestational age of 95 (90 to 100) days (term, 145). Fourteen nonoperated fetuses served as controls. The intended duration of obstruction was 15 days. Study parameters consisted of operating time, fetal survival, performance of the balloon, and pulmonary changes.

RESULTS

Hysterotomy time was 41 +/- 25 minutes and tracheoscopy time was 7.2 +/- 3.4 minutes. There were no intraoperative deaths in this series. Postoperative fatalities occurred in 2 of 13 plugged fetuses and 1 of 14 controls. At completion of the experiment, the balloon was recovered intact in the trachea of 12 of 13 (92.3%) fetuses. The lung weight/body weight ratio was 76 +/- 16 mg/kg for plugged animals, while in controls it was 34 +/- 8 mg/kg (P = .0001). The lung volume/body weight ratio was 101 +/- 17 mL/kg in plugged fetuses, compared with 47 +/- 4 mL/kg for controls (P = .0002). Mean-terminal-bronchial-density was 0.937 +/- 0.303 for plugged animals, compared with 1.911 +/- 0.441 for controls (P = .0002). Mean linear intercept was 60.9 +/- 5.2 microm in treated fetuses, and 46.3 +/- 5.8 microm for controls (P = .0004).

CONCLUSIONS

Fetal endotracheal occlusion, using a tracheoscopically placed detachable balloon, is reliable, and results in pulmonary hyperplasia after 2 weeks of obstruction. This technique may be beneficial in treating the pulmonary hypoplasia seen in congenital diaphragmatic hernia. Further studies using this balloon device are now required to corroborate these findings.

Access techniques in endoscopic fetal surgery

Endoscopic surgery may in the future become an attractive alternative to open fetal surgery. Herein, we present our evolving experience with minimal access techniques in sheep and nonhuman primate models. Fifty-two pregnant sheep (term = 145 d) were used. All underwent laparotomy. Cannulas were 5 mm diameter with balloon fixation device. In group I (95-105 d, n = 22, and 70-74 d, n = 19), a total of 119 cannulas were placed by open hysterotomy and pursestring suture through myometrium and membranes. In group II (n = 11), access was obtained by Seldinger guidewire technique. Eight cannulas were introduced over a dilator and 7 were radially expanding endoscopic cannulas. Fifteen cannulas were also placed in 5 pregnant Rhesus monkeys using Seldinger and radially expanding techniques. Cannula removal was followed by insertion of a collagen sponge plug and oversewing of the myometrium. Mini-hysterotomies with purse-stringing provided excellent access to the amniotic cavity, without dissection of the membranes. Classic Seldinger technique with forward dilatation was equally effective, but caused stretching of membranes. In sheep and in primates, Seldinger technique with radial dilatation allowed safe access without membrane separation. Leak-proof removal of the cannulas was achieved in all primates. Open hysterotomy with purse-string and balloon-tipped cannula provides efficient and safe access to the gravid sheep uterus. Seldinger technique allows equally secure access, and alleviates the need for hysterotomies. Radial dilatation of the porthole eliminates forward dissection of the membranes, both in sheep and primate models. This method, and collagen plug insertion upon completion of the endoscopic procedure, may provide a truly minimally invasive approach to in-utero surgery.

Diagnostic echographic findings in cryptophthalmos syndrome (Fraser syndrome)

We report two male siblings with cryptophthalmos syndrome (Fraser syndrome), an autosomal recessive multiple malformation syndrome with cryptophthalmos, abnormal genitalia, and syndactyly of the fingers and toes as major clinical symptoms. Renal anomalies (uni- or bilateral agenesis) occur in 85 per cent. In the second trimester of both pregnancies (at 23.5 and 18.5 weeks, respectively), echographic examination revealed multiple anomalies: oligoamnios sequence and fetal hydrops with nuchal oedema. Contrasting with the oligohydramnios, the lungs were voluminous and hyperechogenic. Fetopathological examination revealed that the oligoamnios sequence was due to major renal abnormalities (bilateral renal agenesis in the first, and unilateral renal agenesis and contralateral multicystic renal dysplasia in the second sibling). Laryngeal substenosis had resulted in another malformation sequence consisting of overdistended lungs, and non-immune fetal hydrops. The present experience shows that in the presence of an oligoamnios sequence with contrastingly voluminous, hyperechogenic lungs, the diagnosis of cryptophthalmos syndrome should seriously be considered in the differential diagnosis.

Chromosome 22q11 deletion presenting as the Potter sequence

A female fetus with the Potter sequence, caused by unilateral renal agenesis and contralateral multicystic renal dysplasia, was found to have a submicroscopic deletion in chromosome 22q11. The only associated anomaly was agenesis of the uterus and oviducts (Von Mayer-Rokitansky-Küster anomaly). The deletion was inherited from the father, who presented the typical velocardiofacial syndrome phenotype, but no urological anomalies. This observation further extends the clinical spectrum associated with a deletion in 22q11.

Amnioinfusion with Hartmann's solution: a safe distention medium for endoscopic fetal surgery in the ovine model

In this study, we have investigated the maternal effects of distending the uterine cavity with Hartmann's solution in 2nd trimester equivalent pregnant sheep. In 7 pregnant ewes, double endoscopic cannulation of the amniotic cavity was performed under general anesthesia, and 1 liter of Hartmann's solution at 38 degrees C, radiolabeled with 99mTc-red blood cells, was infused. Maternal central venous pressure, hematocrit, serum and amniotic fluid osmolarity, and amniotic fluid volume were measured at nine time points within a 2-hour period. Over this time interval, no significant fluid shift to the maternal compartment was observed. We detected no adsorption of radioactivity to the fetus or membranes, and no diffusion of radioactivity to maternal or fetal tissues was noticed. We conclude from these experiments that following double cannulation and intra-amniotic infusion of Hartmann's solution into the 2nd-trimester pregnant ovine uterus, no significant shift of fluid to the maternal compartment was observed over a 2-hour time period.

Prenatal diagnosis in Belgium

Prenatal diagnoses (PND) in Belgium are performed exclusively in licensed centres of medical genetics linked to university hospitals. These centres of genetics provide comprehensive genetic services which include, in addition to genetic tests, genetic counselling and moral support. These services are accessible to all residents in Belgium through coverage by the social security. PND has become a widely accepted procedure by the public and the health professionals, and has achieved significant prevention of birth defects, mainly chromosome abnormalities. The main problems involved in PND in Belgium are (1) the lack of regulations about indications for PND and (2) insufficient education in medical genetics in medical schools. It is hoped that the basic organisation of PND in Belgium will prevail in the future, with the proposed improvements.

Underwater Nd:YAG laser coagulation of blood vessels in a rat model

Endoscopic coagulation of placental and umbilical cord vessels has been suggested as a treatment for selected cases of twin-twin transfusion syndrome and of acardiac twin. The feasibility, safety and hemostatic effect of neodymium:yttrium-aluminium-garnet (Nd:YAG) laser in an underwater environment were experimentally studied in an in vivo model, mimicking the in utero situation and fetoplacental vessels. In 10 male Wistar rats, immersed in normal saline at 38 degrees C, femoral vessels, carotid artery, abdominal aorta and vena cava were coagulated under endoscopic control. A 100-Watt Nd:YAG laser was used in continuous mode with a 600-micron fiber. Outcome measurements were vascular diameter, total energy (joules) used to obtain visual coagulation and subsequent vascular obliteration. Overall failure rate was 32% and perforation of the vessel occurred in 7.7% of cases.

Endoscopic In Utero Tracheal Plugging in the Fetal Lamb to Treat Congenital Diaphragmatic Hernia

A case control surgical trial was performed in 13 time-dated pregnant ewes to evaluate the feasibility and pulmonary effects of intratracheal obstruction by an endoscopically positioned balloon. Fifteen fetuses were subjected to tracheoscopic balloon obstruction for progressively longer periods (range 2-18 days). In case of multiple pregnancies, 10 other fetuses were used as negative controls. A 1.2-mm miniscope with a double-lumen sheath and a detachable balloon were used. Feasibility of the technique was assessed in all animals based on operating time, intraoperative complications, and tracheal obstruction. Pulmonary effects were assessed by lung-to-body weight ratio (LBWR) and morphometric terminal brachial density (MTBD). In 14 animals the trachea was successfully obstructed until delivery. Tracheoscopic manipulation time ranged from 3 to 14 minutes. One intraoperative death occurred, but the contralateral control fetus also died during the procedure. When obstruction lasted for more than 7 days, the mean LBWR was 0.060 &plusmn; 0.01 (range 0.051-0.075) and in controls 0.031 &plusmn; 0.01 (range 0.017-0.039, p <0.0005). The MTBD was 0.65 &plusmn; 0.59, compared with 1.30 &plusmn; 0.80 for controls. Using a simple and fast technique of fetoscopic tracheoscopy, the trachea can be obstructed, leading to pulmonary hyperplasia, which is of potential value when treating congenital diaphragmatic hernia.

Fetoscopic Nd:YAG Laser Coagulation for Twin-Twin Transfusion Syndrome in Cases of Anterior Placenta

Laser coagulation of anastomosing placental chorionic plate vessels was suggested as a treatment of severe twin-twin transfusion syndrome in midtrimester. An anteriorly located placenta may hamper access and visualization of the vessels involved. We treated six women with completely anterior placenta at 18 to 22 weeks' gestation. Through a 2- to 3-cm minilaparotomy the uterus was accessed after retraction of the viscera. A flexible cannula was inserted through the uterine fundus, and a 35-degree, 0.20-mm minifibroscope and 400-mm fiber were introduced. All vessels crossing the intertwining membrane were coagulated in a continuous mode and a maximum output of 45 W. All fetuses survived the operation. One fetus died in utero 6 weeks postoperatively from cardiac failure, and its receptor twin was born alive. All other pregnancies are either continuing, or the women delivered two healthy babies. Thus far, total fetal survival is 91.6%, compared with results with posterior-sided placentas. Neodymium:yttrium-aluminum-garnet laser coagulation is also possible in case of anterior placenta, but requires a minimal maternal incision and general anesthesia to allow safe cannula placement. A bent scope allows for a larger placental surface to be treated.

The effect of open and endoscopic fetal surgery on uteroplacental oxygen delivery in the sheep

Open fetal surgery predictably results in postoperative uterine contractions and often in premature labor, but its intraoperative effects on the uterus are not known. In 10 pregnant ewes (108 to 115 days' gestation), uterine artery flow, uterine venous oxygen saturation, arterial saturation, and uterine electromyography were recorded simultaneously (control). Six ewes underwent a stapled hysterotomy, and four underwent placement of three endoscopic surgery cannulas and amnioinfusion. Uterine contractions were present 52% of the time (range, 34% to 72%), and there was no significant difference between control, hysterotomy, and endoscopic access. Uterine artery blood flow and uteroplacental oxygen delivery at rest decreased (to 73% of control) after hysterotomy (P < .05), but not after endoscopy. Fetal + uteroplacental oxygen consumption did not differ significantly between the groups. In conclusion, (1) uteroplacental oxygen delivery after hysterotomy alone decreased to levels critical for adequate fetal oxygenation; (2) endoscopy did not alter uteroplacental oxygen delivery; and (3) during open fetal surgery, further oxygen demand/delivery mismatch is likely, by traction on uterine and umbilical vessels and fetal stress.

Caffeine counteracts the ergogenic action of muscle creatine loading

This study aimed to compare the effects of oral creatine (Cr) supplementation with creatine supplementation in combination with caffeine (Cr+C) on muscle phosphocreatine (PCr) level and performance in healthy male volunteers (n = 9). Before and after 6 days of placebo, Cr (0.5 g x kg-1 x day-1), or Cr (0.5 g x kg-1 x day-1) + C (5 mg x kg-1 x day-1) supplementation, 31P-nuclear magnetic resonance spectroscopy of the gastrocnemius muscle and a maximal intermittent exercise fatigue test of the knee extensors on an isokinetic dynamometer were performed. The exercise consisted of three consecutive maximal isometric contractions and three interval series of 90, 80, and 50 maximal voluntary contractions performed with a rest interval of 2 min between the series. Muscle ATP concentration remained constant over the three experimental conditions. Cr and Cr+C increased (P < 0.05) muscle PCr concentration by 4-6%. Dynamic torque production, however, was increased by 10-23% (P < 0.05) by Cr but was not changed by Cr+C. Torque improvement during Cr was most prominent immediately after the 2-min rest between the exercise bouts. The data show that Cr supplementation elevates muscle PCr concentration and markedly improves performance during intense intermittent exercise. This ergogenic effect, however, is completely eliminated by caffeine intake.

Significance of insulin for glucose metabolism in skeletal muscle during contractions

Glucose uptake rate in active skeletal muscles is markedly increased during exercise. This increase reflects a multifactorial process involving both local and systemic mechanisms that cooperate to stimulate glucose extraction and glucose delivery to the muscle cells. Increased glucose extraction is effected primarily via mechanisms exerted within the muscle cell related to the contractile activity per se. Yet contractions become a more potent stimulus of muscle glucose uptake as the plasma insulin level is increased. In addition, enhanced glucose delivery to muscle, which during exercise is essentially effected via increased blood flow, significantly contributes to stimulate glucose uptake. Again, however, increased glucose delivery appears to be a more potent stimulus of muscle glucose uptake as the circulating insulin level is increased. Furthermore, contractions and elevated flow prove to be additive stimuli of muscle glucose uptake at any plasma insulin level. In conclusion, the extent to which muscle glucose uptake is stimulated during exercise depends on various factors, including 1) the intensity of the contractile activity, 2) the magnitude of the exercise-associated increase in muscle blood flow, and 3) the circulating insulin level.

No effect of glycogen level on glycogen metabolism during high intensity exercise

This study examined the effect of glycogen supercompensation on glycogen breakdown, muscle and blood lactate accumulation, blood-pH, and performance during short-term high-intensity exercise. Young healthy volunteers performed two supramaximal (125% of VO2max) exercise tests on a bicycle ergometer, either for 1 min 45 s (protocol 1; N = 18) or to exhaustion (protocol 2; N = 14). The exercise tests were preceded by either 5 d on a controlled normal (N) diet, or by 2 d of glycogen-depleting exercise accompanied by the normal diet followed by 3 d on a carbohydrate-rich (CHR) diet. In protocol 1, preexercise muscle glycogen concentrations were 364 +/- 23 and 568 +/- 35 mumol.g-1 d.w. in the N and CHR condition, respectively (P < 0.05). During the exertion, glycogen concentration in the M. quadriceps decreased to the same extent in both groups. Accordingly, the exercise-induced increases in muscle and blood-lactate, and the fall in blood-pH were similar during N and CHR. In protocol 2, time to exhaustion was identical for N and CHR. It is concluded that during short-term intense exercise during which muscle glycogen availability exceeds glycogen demand, rate of glycogen breakdown, lactate accumulation, and performance are regulated irrespective of the preexercise muscle glycogen level.