[The results of ulnar nerve decompression in Guyon's canal syndrome]

PURPOSE OF THE STUDY

The aim of the study was to evaluate a group of patients treated for Guyon's canal syndrome with analysis of the cause for and outcome of surgery.

MATERIAL AND METHODS

The group comprised 13 patients operated on for compressive neuropathies of the ulnar nerve in the canal of Guyon in the period from 2007 to 2010. The clinical parameters evaluated were the adduction strength of the fifth digit, degree of interosseous primus muscle hypotrophy and degree of hypoesthesia in the area innervated by the ulnar nerve. EMG parameters included motor and sensory nerve conduction through Guyon's canal. Patients' subjective evaluations of the treatment outcomes were also recorded. The results were not compared with a control group.

RESULTS

Post-operative improvements in all clinical and EMG parameters were significant (p=0.02-0.003). All but one patient (90%) reported an improved subjective condition after surgery; on the other hand, pre-operative severe impairment of motor nerve conduction highly affected the post-operative motor function. Guyon's canal syndrome accounted for 0.8% of all compressive neuropathies of the upper extremity in our patients.

DISCUSSION

Ulnar nerve compression at the wrist is a relatively rare condition amongst the compressive neuropathies of the upper extremity, and literature data concerning this disease are very few. Although many causes of ulnar nerve compression at the wrist have been reported, only one of our patients had ganglion. We conclude that the majority of cases can be diagnosed as a "neuritis" due to chronic microtrauma produced by pressure of a hypertrophic palmar ligament.

CONCLUSIONS

Syndrome of Guyon's canal can easily be treated by surgery. As in other compression syndromes, the sooner a surgical decompression is performed, the better outcomes are achieved.

[Surgery for sciatic nerve injuries]

PURPOSE OF THE STUDY

Injury to the sciatic nerve is a rare event. Apart from war time surgery, it usually presents as a closed lesion caused by traction. The aim of the study was to evaluate a group of patients treated for sciatic nerve injury, with an analysis of the cause for and the outcome of surgery.

MATERIAL AND METHODS

In this prospective study, the results in ten patients treated surgically were evaluated. Five patients underwent exoneurolysis, two were treated by end-to-end suture of the nerve and three by suture and sural nerve grafting. One patient was lost to follow-up and nine were followed up for minimally 24 months after surgery.

RESULTS

In the patients treated by exoneurolysis, sciatic nerve function recovered in the peroneal division in 60%, and in the tibial portion in 100% of them. The result depended mainly on the inter val between injury and surgery. Of four patients with direct suture of the nerve or with sural nerve grafting, function of the tibial portion recovered in three (75%) and that of the peroneal portion in one (25%).

CONCLUSIONS

Although the course of the sciatic ner ve is ver y long, its surgical treatment is fully justified because it shows good results even in buttock-level and thigh-level nerve injuries.

Phase I study of BIBF 1120 with docetaxel and prednisone in metastatic chemo-naive hormone-refractory prostate cancer patients

Background:

BIBF 1120 is an oral, potent, tyrosine kinase inhibitor that simultaneously targets vascular endothelial growth factor receptors 1–3, platelet-derived growth factor receptors α and β, and fibroblast growth factor receptors 1–3, as well as FLT3 and Src. Currently, the molecule is in phase III development for second-line non-small cell lung cancer and first-line ovarian cancer patients.

Methods:

This phase I dose-escalation study assessed the safety and maximum tolerated dose of continuous daily treatment with BIBF 1120 plus standard-dose docetaxel (75 mg m⁻², every 3 weeks) and prednisone (5 mg BID) in patients with metastatic, chemo-naive, hormone-refractory prostate cancer (HRPC). Secondary objectives were characterisation of BIBF 1120 and docetaxel pharmacokinetics (PK), and preliminary antitumour activity.

Results:

Patients received BIBF 1120 100 mg BID (n=3), 150 mg BID (n=3), 200 mg BID (n=3), and 250 mg BID (n=12). The most frequent drug-related adverse events were diarrhoea (71.4%), asthenia (61.9%), nausea (28.6%), vomiting (28.6%), and alopecia (23.8%). The maximum tolerated dose was 250 mg BID of BIBF 1120. Overall, reversible grade 3/4 liver enzyme elevations occurred in six of twelve patients at this dose level. Among 19 assessable patients, 13 (68.4%) showed a ⩾50% reduction in prostate serum antigen levels from baseline and among 6 evaluable patients with measurable lesions 1 patient experienced a partial response by Response Evaluation Criteria In Solid Tumours criteria. Pharmacokinetic analysis showed no interactions between BIBF 1120 and docetaxel/prednisone.

Conclusion:

Based on the overall safety profile, 200 mg BID was the recommended dose for the combination of BIBF 1120 with the standard dose of 75 mg m⁻² of docetaxel and prednisone that might be further investigated in HRPC patients. This combination was well tolerated, with preliminary signs of efficacy and no indication of PK interaction between BIBF 1120 and docetaxel.

A phase II double-blind study to investigate efficacy and safety of two doses of the triple angiokinase inhibitor BIBF 1120 in patients with relapsed advanced non-small-cell lung cancer

BACKGROUND

To assess the efficacy, safety, tolerability and pharmacokinetics of BIBF 1120 in patients with stage IIIB/IV non-small-cell lung cancer (NSCLC).

METHODS

Patients with locally advanced or metastatic relapsed NSCLC in whom first- or second-line platinum-based chemotherapy failed were randomly allocated to daily 250 mg BIBF 1120 b.i.d. or 150 mg BIBF 1120 b.i.d. Primary end points were progression-free survival (PFS) and objective tumour response (RECIST). Incidence and severity of adverse events (AEs) were reported.

RESULTS

Seventy-three patients received BIBF 1120. Median PFS was 6.9 weeks, with no significant difference between treatment arms. Median overall survival (OS) was 21.9 weeks. Eastern Cooperative Oncology Group (ECOG) 0-1 patients (n = 56) had a median PFS of 11.6 weeks and a median OS of 37.7 weeks. Tumour stabilisation was achieved in 46% of patients (ECOG 0-1 patients: 59%), with one confirmed partial response (250 mg b.i.d.). Most commonly reported drug-related AEs were nausea (57.5%), diarrhoea (47.9%), vomiting (42.5%), anorexia (28.8%), abdominal pain (13.7%) and reversible alanine transaminase (13.7%) and aspartate aminotransferase elevations (9.6%). BIBF 1120 displayed dose-linear pharmacokinetic characteristics.

CONCLUSION

Continuous treatment with BIBF 1120 was well tolerated, with no difference in efficacy between treatment arms. PFS and objective response with single-agent treatment in advanced disease warrants further exploration.

[Lumbo-pelvic stabilisation following subtotal sacrectomy due to a giant invasive schwannoma. Case report]

The case of a rare giant invasive schwannoma of the sacrum is presented. This is a slow-growing tumour reaching a large size because of non-specific symptoms. Even though it is benign in nature, it has characteristics markedly differing from commonly-known neurinomas; it invades and destroys bone, on MR examination it shows a heterogeneous structure reminiscent of a malignant process and its growth around the nerve roots makes nerve dissection in the cauda equina very complicated. At the time of diagnosis a major part of the sacral bone is usually destroyed and nerve root dissection is very difficult. In this case, because of removal of most of the tissue, an almost complete sacrectomy was necessary including the sacral roots with the exception of S1. At the second stage, lumbo-pelvic stabilisation was carried out using the modified Galveston technique. Since only a very few similar cases have been reported, it is not possible to predict the post-operative outcome in terms of potential recurrence or residual progression. In our patient a small residuum was stable even at 37 months after surgery. She remained incontinent after surgery, but able to walk unaided. Radiographic examination showed the osteosynthetic material without signs of loosening and in a good position.

[Vascular endothelial growth factor]

VEGF, vascular endothelial growth factor, is a substance firstly described in 1983 as a tumor-secreted protein which causes the development of ascitic fluid in case of abdominal tumors. Its influence on angiogenesis was ascertained by many studies. The strongest stimulus for its production is hypoxia, which leads to higher secretion of VEGF and new angiogenesis of so affected tissue. The neurogenic effect was firstly mentioned in 1999. Its protective and proliferative influence both on CNS and peripheral nerves is now widely accepted. It was demonstrated that VEGF has more wide ranging effect than previously thought.

Effects of OCT1 polymorphisms on the cellular uptake, plasma concentrations and efficacy of the 5-HT(3) antagonists tropisetron and ondansetron

After uptake into liver cells, the antiemetic drugs tropisetron and ondansetron undergo metabolic inactivation by cytochrome P450 2D6 (CYP2D6). We investigated whether the hepatic organic cation transporter 1 (OCT1; SLC22A1) mediates cellular uptake and whether common OCT1 loss-of-function polymorphisms affect pharmacokinetics and efficacy of both drugs. Both tropisetron and ondansetron inhibited ASP(+) uptake in OCT1-overexpressing HEK293 cells. Overexpression of wild-type, but not OCT1 loss-of-function variants, significantly increased tropisetron uptake. Correspondingly, patients with two loss-of-function OCT1 alleles had higher tropisetron plasma concentrations (n=59, P<0.04) and higher clinical efficacy (n=91, P=0.009) compared with carriers of fully active OCT1. Overexpression of OCT1 did not increase ondansetron uptake. Nevertheless, OCT1 genotypes correlated with pharmacokinetics (n=45, P<0.05) and clinical efficacy (n=222, P<0.02) of ondansetron, the effect size of OCT1 genotypes on pharmacokinetics and efficacy was greater for tropisetron than for ondansetron. In conclusion, in addition to the known effects of CYP2D6, OCT1 deficiency may increase efficacy of tropisetron and potentially of ondansetron by limiting their hepatic uptake.

Blood donors in Kenya: a comparison of voluntary and family replacement donors based on a population-based survey

BACKGROUND AND OBJECTIVES

Blood safety and sufficiency are major challenges in Kenya and other sub-Saharan African countries forcing many countries to rely on family replacement donors (FRD). We analysed data from a national AIDS indicator survey to describe blood donors in Kenya and potential risks of transfusion transmissible infections (TTI) comparing voluntary donors and FRD.

MATERIALS AND METHODS

A population-based, cross-sectional survey was conducted in 2007 among 15- to 64-year-olds. Consenting participants were interviewed about blood donation history and were tested for HIV, HSV-2 and syphilis.

RESULTS

Of the 17,940 people surveyed, 445 (2·3%) reported donating blood in the prior 12 months. Sixty-four per cent were voluntary donors, and the rest were FRD. Compared to FRD, the majority of voluntary donors were <25 years old (59% versus 18%), from the highest wealth quintile (57% versus 42%) and single (64% versus 23%). In addition, voluntary donors were less likely to have been sexually active than replacement donors (43% versus 13%). HIV prevalence was lower among voluntary donors than among FRD (2·6% versus 7·4%, P-value=0·07).

CONCLUSIONS

The majority of blood donors in Kenya are voluntary with lower potential risk of TTI.

Maraviroc in treatment-experienced patients with HIV-1 infection - experience from routine clinical practice

OBJECTIVE

Few data are available about the efficacy of maraviroc (MVC) during routine use. We characterized indications for MVC use and the efficacy of MVC in clinical practice.

METHODS

Thirty-two patients treated with MVC at our institution between 2006 and 2009 were included. Genotypic (n +/- 31) and phenotypic (n +/- 13) tropism analysis was performed. We determined indications for MVC use, characteristics of antiretroviral combination partners and treatment outcome.

RESULTS

Complete suppression of viral replication was achieved in 78% after 6 months. A median increase of 124 CD4+ cells/microl after 6 months was observed. Concordance between phenotypic and genotypic tropism was found in 75%. Indications for MVC treatment included treatment failure (n +/- 15), intolerance to previous antiretrovirals (n +/- 6) and add-on MVC for intensification without changing the current regimen (n +/- 11). The add-on strategy was used in patients with a relatively low viremia in order to achieve complete viral load suppression or in situations with suppressed viral load but judged as unstable due to an extensive resistance pattern. Salvage drugs most frequently combined with MVC were darunavir (n +/- 14) and raltegravir (n +/- 14). - The genotypic assay had predicted CXCR4 tropism in 5 patients, using a false positive rate (FPR) of 20%. Lowering the FPR to 5% predicted CCR5 tropism in 4 cases, still resulting in sustained complete viral response under MVC use.

CONCLUSIONS

MVC containing salvage regimens achieve relevant CD4 cell increases and high viral response rates. In patients with few remaining treatment options it may be justified to lower the FPR-cutoff to 5% when predicting the coreceptor usage. Hereby, MVC could still be applied in selected patients with otherwise limited treatment options.

Prediction of response to antiretroviral therapy by human experts and by the EuResist data-driven expert system (the EVE study)

OBJECTIVES

The EuResist expert system is a novel data-driven online system for computing the probability of 8-week success for any given pair of HIV-1 genotype and combination antiretroviral therapy regimen plus optional patient information. The objective of this study was to compare the EuResist system vs. human experts (EVE) for the ability to predict response to treatment.

METHODS

The EuResist system was compared with 10 HIV-1 drug resistance experts for the ability to predict 8-week response to 25 treatment cases derived from the EuResist database validation data set. All current and past patient data were made available to simulate clinical practice. The experts were asked to provide a qualitative and quantitative estimate of the probability of treatment success.

RESULTS

There were 15 treatment successes and 10 treatment failures. In the classification task, the number of mislabelled cases was six for EuResist and 6-13 for the human experts [mean±standard deviation (SD) 9.1±1.9]. The accuracy of EuResist was higher than the average for the experts (0.76 vs. 0.64, respectively). The quantitative estimates computed by EuResist were significantly correlated (Pearson r=0.695, P<0.0001) with the mean quantitative estimates provided by the experts. However, the agreement among experts was only moderate (for the classification task, inter-rater κ=0.355; for the quantitative estimation, mean±SD coefficient of variation=55.9±22.4%).

CONCLUSIONS

With this limited data set, the EuResist engine performed comparably to or better than human experts. The system warrants further investigation as a treatment-decision support tool in clinical practice.

Floral biology and reproductive isolation by floral scent in three sympatric aroid species in French Guiana

We studied the reproductive biology of three sympatric Araceae species, Anthurium sagittatum, A. thrinax and Spathiphyllum humboldtii in French Guiana. The plants flowered simultaneously and were visited by scent-collecting male euglossine bees, which were apparently their major pollinators. In total, each species was visited by 3-7 euglossine species, and 2-3 euglossine species accounted for at least 80% of all flower visits, with visits being plant species-specific. Floral scent consisted of 6-10 main compounds, which made up 76-94% of the total amount of volatiles and were specific in these high amounts to each plant species. We suggest that the different floral scents lead to clear separation of the main pollinating euglossine species, providing a directed and efficient intraspecific pollen flow that results in high reproductive success. Since the simple floral (inflorescence) morphology of the studied plants does not support any morphological mechanisms to exclude visitors, as for example in euglossine-pollinated perfume orchids, floral scent might be of major importance for the reproductive isolation and sympatric occurrence of these plants.

Observation of a cooperative radiation force in the presence of disorder

Cooperative scattering of light by an extended object such as an atomic ensemble or a dielectric sphere is fundamentally different from scattering from many pointlike scatterers such as single atoms. Homogeneous distributions tend to scatter cooperatively, whereas fluctuations of the density distribution increase the disorder and suppress cooperativity. In an atomic cloud, the amount of disorder can be tuned via the optical thickness, and its role can be studied via the radiation force exerted by the light on the atomic cloud. Monitoring cold (87)Rb atoms released from a magneto-optical trap, we present the first experimental signatures of radiation force reduction due to cooperative scattering. The results are in agreement with an analytical expression interpolating between the disorder and the cooperativity-dominated regimes.

[Neuroborreliosis]

Neuroborreliosis is easily diagnosed by means of clinical symptoms and laboratory findings. Guiding symptoms are radicular pain and pareses of the extremities and the facial nerve. There is a great number of further less frequently occurring neurological symptoms, which can be attributed to a borrelial infection only by appropriate investigations of the CSF. Radiculitis is cured adequately by oral doxycycline while symptoms of the central nervous system are probably better treated intravenously by ceftriaxone, cefotaxime or penicillin G. Post-Lyme syndrome is a diffuse description of non-specific complaints, which are not the explicit result of a former infection with B. burgdorferi. As further antibiotics do not help and the CSF is unremarkable in most patients, a persistent infection with B. burgdorferi s.l. in all probability can be excluded.