Isolated bulbar paralysis in a patient with medullar tau pathology: a case report

Increased morbidity and mortality rates as well as some other manifestations in Alzheimer's disease can be explained by subcortical degeneration. Pathological evidence is scarce but confirmative. We report a 77-year-old patient who presented with a 6-year history of dyspnoea, stridor and dysphagia. Unexpectedly, histopathological examination disclosed extensive degeneration of the medulla by tau pathology. The majority of symptoms and signs could be explained by the medullary tau pathology. Whether the medullary tau pathology in this case was a rare aberrant progression of Alzheimer's disease or a new presentation of tauopathy concomitant with subclinical Alzheimer's disease should be elucidated by additional studies.

Dietary influence on breast cancer

Certain lifestyle and environmental factors play an important role on breast cancer (BC) risk, but data on the influence of nutritional factors are still conflicting. Migrational data have pointed to nutrition as one of the more relevant external factors involved. So far, the only well established nutrition-related risk factors for BC are obesity and alcohol consumption. The evidence that body fatness is a cause of postmenopausal breast cancer is convincing as is the evidence that alcoholic drinks are a cause of BC in all ages. On the other hand, body fatness probably protects against BC diagnosed premenopause. It is more likely that the BC risk is related to life-long dietary habits. The general preventive recommendation often includes a reduction of alcohol, red meat and total dietary fat, and increase in vegetable and fruit consumption. The purpose of this work was to summarize and present current opinions on the influence of diet and nutrition on BC etiology and to suggest possible preventive measures.

Nevirapine hypersensitivity

Treatment of HIV-1 infections with nevirapine is associated with skin and liver toxicity. These two organ toxicities range from mild to severe, in rare cases resulting in life-threatening liver failure or toxic epidermal necrolysis. The study of the mechanistic steps leading to nevirapine-induced skin rash has been facilitated by the discovery of an animal model in which nevirapine causes a skin rash in rats that closely mimics the rash reported in patients. The similarity in characteristics of the rash between humans and rats strongly suggests that the basic mechanism is the same in both. The rash is clearly immune-mediated in rats, and partial depletion of CD4(+) T cells, but not CD8(+) T cells, is protective. We have demonstrated that the rash is related to the 12-hydroxylation of nevirapine rather than to the parent drug. This is presumably because the 12-hydroxy metabolite can be converted to a reactive quinone methide in skin, but that remains to be demonstrated. Although the rash is clearly related to the 12-hydroxy metabolite rather than the parent drug, cells from rechallenged animals respond ex vivo to the parent drug by producing cytokines such as interferon-gamma with little response to the 12-hydroxy metabolite, even when the rash was induced by treatment with the metabolite rather than the parent drug. This indicates that the response of T cells in vitro cannot be used to determine what caused an immune response. We are now studying the detailed steps by which the 12-hydroxy metabolite induces an immune response and skin rash. This animal model provides a unique tool to study the mechanistic details of an idiosyncratic drug reaction; however, it is likely that there are significant differences in the mechanisms of different idiosyncratic drug reactions, and therefore the results of these studies cannot safely be generalized to all idiosyncratic drug reactions.

Factors affecting results of treatment of Hypopharyngeal Carcinoma

OBJECTIVE

A retrospective review of patients with malignant neoplasms of the hypopharynx treated with combined surgery and radiotherapy is presented to highlight the results of treatment and the factors of treatment success for this malignant disease.

PATIENTS AND METHODS

Between 1995 and 2004 at the University ORL Clinic Nis 89 patients with malignant neoplasms of hypopharynx (85 males, 4 females, and age ranging from 44 to 77 years) were treated. In the 89 patients (stage I, n=4; stage II, n=3; stage III, n=34; stage IV, n=48), the sites of origin were pyriform sinus (n=75), postcrycoid (n=8), posterior pharyngeal wall (n=3) and superior hypopharynx (n=3).

RESULTS

Laryngeal preservation surgery was achieved in 11.2% of patients, while 88.8% had laryngectomy with partial or total pharyngectomy. Pyriform sinus was the most common site of origin of hypopharyngeal carcinoma in 84.3%. Totally 93% of patients had neck metastases, and tumors extended beyond the hypopharynx in 41.6% of patients. TNM stage was highly significant parameter of outcome. Five year survival was 100% for stage I, 66.6% for stage II, 53.9% for stage III, and 33.3% for stage IV. Residual disease (5.6%) and recurrent disease (2.2%) were low. Postoperative fistula developed in 16.8% of patients, and in 60% it was closed successfully using local flaps, while in 40% pectoralis flap was needed. Localization of disease was also an important factor of survival. Retrocrycoid carcinoma resulted in very poor survival rate (12.5%), high residual disease, lymph node metastasis, and pharyngocutaneous fistula formation.

CONCLUSION

Localization and TNM stage are highly significant factors for clinical course, treatment, and outcome of hypopharyngeal carcinoma.

Thrombin-induced expression of endothelial CX3CL1 potentiates monocyte CCL2 production and transendothelial migration

CX3CL1 (fractalkine, neurotactin) is the sole CX3C chemokine. It induces monocyte locomotion in its cleaved form, but in its membrane-anchored form, it also acts as an adhesion molecule. The expression of CX3CL1 is up-regulated in endothelial cells by proinflammatory cytokines such as IL-1 or TNF-alpha. Here, we studied the effect of the serine protease thrombin on endothelial CX3CL1 induction and its putative relevance for monocyte function. In HUVEC, thrombin triggered a time- and concentration-dependent expression of CX3CL1 at the mRNA and the protein level as shown by RT-PCR, Western immunoblotting, and flow cytometric analysis. Thrombin induced CX3CL1 by activating protease-activated receptor 1 (PAR1) as demonstrated by the use of PAR1-activating peptide and the PAR1-specific antagonist SCH 79797. The thrombin-induced CX3CL1 expression was NF-kappaB-dependent, as shown by EMSA, ELISA, and by inhibition of the NF-kappaB signaling pathway by the IkappaB kinase inhibitor acety-11-keto-beta-boswellic acid or by transient overexpression of a transdominant-negative form of IkappaBalpha. Upon cocultivation of human monocytes with HUVEC, the thrombin-dependent induction of membrane-anchored CX3CL1 in HUVEC triggered monocyte adhesion and an enhanced release of the MCP-1/CCL2 by monocytes and potentiated the monocyte transendothelial migration. Accordingly, the recombinant extracellular domain of CX3CL1 induced CCL2 release by monocytes. Thus, the thrombin-induced monocyte/endothelial cell cross-talk mediated by increased CX3CL1 expression potentiates the CCL2 chemokine generation that might contribute to the recruitment of monocytes into inflamed areas.

Random left censoring: a second look at bone lead concentration measurements

Bone lead concentrations measured in vivo by x-ray fluorescence (XRF) are subjected to left censoring due to limited precision of the technique at very low concentrations. In the analysis of bone lead measurements, inverse variance weighting (IVW) of measurements is commonly used to estimate the mean of a data set and its standard error. Student's t-test is used to compare the IVW means of two sets, testing the hypothesis that the two sets are from the same population. This analysis was undertaken to assess the adequacy of IVW in the analysis of bone lead measurements or to confirm the results of IVW using an independent approach. The rationale is provided for the use of methods of survival data analysis in the study of XRF bone lead measurements. The procedure is provided for bone lead data analysis using the Kaplan-Meier and Nelson-Aalen estimators. The methodology is also outlined for the rank tests that are used to determine whether two censored sets are from the same population. The methods are applied on six data sets acquired in epidemiological studies. The estimated parameters and test statistics were compared with the results of the IVW approach. It is concluded that the proposed methods of statistical analysis can provide valid inference about bone lead concentrations, but the computed parameters do not differ substantially from those derived by the more widely used method of IVW.

Anthracycline-based combined chemotherapy in the mouse model

Our research was aimed at establishing if and how selenium (Se) ion, N-acetylcysteine (NAC), sodium salt of monoketocholic acid (MKH) and superoxide-dismutase (SOD), administered in the experimental animal model, could affect the possible cytotoxicity associated with anthracycline-based combined chemotherapy with doxorubicin, vincristine and prednisolone (DVP). The following biochemical parameters were investigated: the extent of lipid peroxidation (LPx), and the activity of peroxidase (Px), catalase (CAT), glutathione-peroxidase (GSHPx), and xanthine-oxidase (XOD). A statistical increase in LPx activity was obtained by SOD, MKH, DVPSe and DVPMKH. All chemotherapeutic agents reduced Px activity in a statistically significant manner. There was no statistical significance for the results regarding the effects of the administered substances on GSHPx activity. The results for DVP, SOD, MKH, DVPSOD, DVPSe and DVPMKH showed reduced XOD activity which was statistically significant, which was lowest in the case of MKH, while NAC and Se reduced the activity of this enzyme but statistically non significant. NAC, Se, DVP, MKH and DVPMKH caused a reduction in CAT activity, while DVPSOD and DVPSe caused an increase of the latter.

Addition of weekly paclitaxel (P) after dose intensified epirubicin/cyclophosphamide (EC) (NECTA-protocol) as primary systemic chemotherapy (PST) in locally advanced breast cancer (LABC) improves pathologic response rate (pCR) in comparison to peoperative dose intensified EC

10712

Background: Green M et al. (Proc Am Soc Clin Oncol 2002, abstract 135) demonstrated an improvement of pCR up to 28,8% by changing the preoperative application of 3 weekly P 225 mg/m2 (q21) to weekly P 80 mg or 150mg/m2 (q7) completed by 4 cycles FAC. Our study-group observed a pCR of 6% after 3 preoperative cycles of dose-intensified EC (120 mg/600 mg/m2 q14 or q21) in LABC. Dose-density (q14) did not improve pCR (Euler U et al. Proc Am Soc Clin Oncol 2002, abstract 126). As a consequence we studied the preoperative effect of 12 cycles P 80 mg/m2 (q7) after 3 cycles EC (120 mg/600 mg/m2 q21) . Methods: Between 2002 and 2005 61 patients (pts) with LABC (T2–4/N0–2/M0) were operated after PST with the NECTA-protocol. Irradiation after breast conserving therapy (BCT) was obligate. Immunohistochemical analysis were performed in tumor tissues from core biopsy before PST and from surgery. Results: The medium age was 49,2 yrs, 29,2% had negative ER-status, 48,1% negative PR-status and 22% HER2 overexpression. 76,2% had a cT2-tumor, 18,6% a cT3-tumor and 5,1% a cT4-tumor, 48,3% clinically showed positive lymph nodes. The medium follow up was 27 months (2–41 months). The clinical and pathological response rate was 94,8%. pCR was diagnosed in 8,6%. BCT was feasible in 94,8%. The documented recurrence rate was 14,7% (9 pts: 4 with local relapse, 3 with metastases and 2 with simultaneous local and distant recurrence), 8 pts with recurrence had a cT2-tumor. In the meantime 3 pts died. Conclusions: The additional treatment with weekly paclitaxel after EC induced a high rate of clinical and pathological response. The rate of conservative surgery was very high (94,8%). In the retrospective analysis NECTA-regime improved pCR. In comparison to other taxane-based PST-protocols pCR-rate (8,6%) was low. A phase III study will compare the NECTA-regime with the classical EC-regime in PST.

No significant financial relationships to disclose.

Neurophysiological effects of mistletoe (Viscum album L.) on isolated rat intestines

Mistletoe (Viscum album L.) is well known as a medicine from ancient times and the earliest notes. Today it is used as a remedy. The aim of this research was to examine the effects of mistletoe extracts and their components on some neurophysiological parameters in rat intestines. The tonus and contractile responses of isolated intestinal segments (duodenum, ileum and distal colon) were analysed. The experiment was carried out in three groups. In the first group (control group) different concentrations of acetylcholine were added into the organ bath (10-50 nmol/L). In the second group, mistletoe extracts were added into the organ bath with increasing concentrations and in the third group, atropine, a non-selective muscarinic receptor antagonist, was added into the organ bath (concentration 10(-7) mol/L) and after atropine plant extracts were administered. The results obtained suggest that extracts from different parts of mistletoe have neurophysiological effects and change intestinal contractions. The results also suggest that the effects of mistletoe extracts on intestinal contractility act via cholinergic pathways, activating muscarinic receptors in the intestines. However, in order to establish the subtype of receptors, further investigations are necessary where selective antagonists of muscarinic cholinergic receptors should be used.

Characterization of upper arm synergies during reaching tasks in able-bodied and hemiparetic subjects

BACKGROUND

In the past, several studies showed the existence of a synergistic behavior between elbow and shoulder joints during reaching movements in able-bodied subjects. The aim of this paper was to characterize the modifications of upper arm synergies during reaching induced by stroke.

METHODS

Ten able-bodied right-handed subjects, eight right-handed subjects with hemiparesis affecting the right (dominant) upper limb participated in the experiments. The kinematics of shoulder and elbow joints have been recorded in all the participants during selected reaching movements. From the eight-like plots characterizing the relationship between shoulder and elbow angular velocities, a topological parameter (named as C approximately ) representing the linear approximation of the synergy between the two angular velocities has been extracted.

FINDINGS

The results of these experiments showed that C approximately could be used as a figure of merit for the comparison of performance in able-bodied and hemiparetic persons. The hemiparetic subjects showed a significantly higher spreading of the values of C approximately for the different reaching movements when compared with the performance of able-bodied subjects.

INTERPRETATION

This work showed that hemiparesis modified upper arm synergies and could provide a protocol for the assessment of upper limb function. Moreover, important applications of this method could be found in the development of biomimetic algorithms for the control of upper extremities during reaching in humanoid robots, and in the design of customized "games" in neurorehabilitation procedures implemented by using robotic and mechatronic platforms.