Axon reflexes or ephaptic responses simulating blink reflex R1 after XII-VII nerve anastomosis

It has been claimed that functional recovery of the blink reflex occurs after hypoglossal-facial nerve anastomosis. This has been explained through central nervous system plasticity and reorganization of neuronal connections. In 5 patients with reinnervated facial muscles after hypoglossal-facial nerve anastomosis, we observed “R1-like” responses that fulfilled criteria for facial nerve axon reflexes or ephapses. First, displacement of the stimulating electrode from the supraorbital to the zygomatic area shortened the latency of the evoked response. Second, these responses were stable (jitter mean consecutive difference < 25 μs) and they had complex potential shapes unmodified by high-frequency stimulation. Finally, collision techniques demonstrated antidromic conduction of impulses in the facial nerve from supraorbital to zygomatic points. Therefore, these “R1-like” responses are not the early component of a functionally recovered blink reflex but motor axon reflexes or ephaptic responses similar to the short latency responses observed following facial nerve regeneration or from sutured nerves in human forearms. © 1996 John Wiley & Sons, Inc.     

γ‐Aminobutyric acid‐ρ expression in ependymal glial cells of the mouse cerebellum

The ependymal glial cells (EGCs) from the periventricular zone of the cerebellum were studied to determine their distribution and the functional properties of their γ‐aminobutyric acid type A (GABA_A) receptors. EGCs were identified by the presence of ciliated structures on their ventricular surface and their expression of glial fibrillary acidic protein (GFAP). Interestingly, diverse cell types, including neurons, astrocytes, and other types of glia, were identified in the subventricular zone by their current profiles. Electron microscopy showed ciliated cells and myelinated axons in this zone, but we found no collateral connections to suggest the presence of functional synapses. GABA‐mediated currents were recorded from EGCs in cerebellar slices from postnatal days 13 to 35 (PN13–PN35). These currents were blocked by TPMPA (a highly specific GABA_Aρ subunit antagonist) and bicuculline (a selective antagonist for classic GABA_A receptors). Pentobarbital failed to modulate GABA_A‐mediated currents despite the expression of GABAα1 and GABAγ2 subunits. In situ hybridization, RT‐PCR, and immunofluorescence studies confirmed GABAρ1 expression in EGCs of the cerebellum. We conclude that cerebellar EGCs express GABAρ1, which is functionally involved in GABA_A receptor‐mediated responses that are unique among glial cells of the brain. © 2013 Wiley Periodicals, Inc.     

Psychotropic drug utilization in Europe: results from the European Study of the Epidemiology of Mental Disorders (ESEMeD) project

OBJECTIVE: To assess psychotropic drug utilization in the general population of six European countries, and the pattern of use in individuals with different DSM-IV diagnoses of 12-month mental disorders. METHOD: Data were derived from the European Study of the Epidemiology of Mental Disorders (ESEMeD/MHEDEA 2000), a cross-sectional psychiatric epidemiological study in a representative sample of 21 425 adults aged 18 or older from six European countries (e.g. Belgium, France, Germany, Italy, the Netherlands and Spain). Individuals were asked about any psychotropic drug use in the past 12 months, even if they used the drug(s) just once. A colour booklet containing high-quality pictures of psychotropic drugs commonly used to treat mental disorders was provided to help respondents recall drug use. RESULTS: Psychotropic drug utilization is generally low in individuals with any 12-month mental disorder (32.6%). The extent of psychotropic drug utilization varied according to the specific DSM-IV diagnosis. Among individuals with a 12-month diagnosis of pure major depression, only 21.2% had received any antidepressants within the same period; the exclusive use of antidepressants was even lower (4.6%), while more individuals took only anxiolytics (18.4%). CONCLUSION: These data question the appropriateness of current pharmacological treatments, particularly for major depression, in which under-treatment is coupled with the high use of non-specific medications, such as anxiolytics.     

Semi-quantitative assessment of cerebral blood flow with 99mTc-HMPAO SPET in type I diabetic patients with no clinical history of cerebrovascular disease

In 65 type I diabetic patients we prospectively evaluated brain perfusion by means of single-photon emission tomography after the injection of 740– 1110 MBq of technetium-99m hexamethylpropylene amine oxime. Thirty-five of the patients presented complications secondary to their diabetes. None showed CNS symptoms. A semiquantitative analysis was performed drawing 50 symmetrical regions of interest (ROIs) per patient. The relative contribution of each ROI to the total blood flow in each slice was compared with the relative contribution of the same ROI in a control group of ten healthy volunteers. Relative values of any ROI in the study group higher or lower than the mean ±2 SD in respect of the same ROI in the control group were considered abnormal. The results revealed hypoperfusion in 207 ROIs in the 65 patients with diabetes mellitus: of these ROIs, 113 were frontal, 10 frontotemporal, 20 temporal, 18 parietal, 11 occipital and 35 cerebellar. A total of 137 ROIs showed hyperperfusion: 17 frontal, 3 frontotemporal, 19 temporal, 18 parietal, 19 parieto-occipital, 29 occipital and 32 cerebellar. Out of 65 type I diabetic patients, 61 showed at least one hypoperfused ROI (P = 0.0064 vs. controls) and 25 showed more than three hypoperfused ROIs. None of the control subjects showed more than three hypoperfused regions (P<0.001). The results obtained demonstrate the existence of subclinical abnormalities of brain blood perfusion in patients with type I diabetes mellitus and no history of cerebrovascular disease, thereby allowing the initiation of intensive preventive measures. Received 16 July and in revised form 16 August 1997     

Usefulness of knee arthroscopy for diagnosis of knee pain in pediatric patients: comparison with preoperative clinical diagnosis

Purpose

To investigate the knee arthroscopic findings of pediatric patients with knee pain.

Subjects

Ninety-five knees of 94 patients (46 males and 48 females) aged 15 years or younger who underwent knee arthroscopy during a 4-year period from January 2007 were studied. The mean age at surgery was 13.5 (7–15) years. The mean interval from symptom onset to arthroscopic examination was 6.8 months (5 days to 2 years 10 months).

Results

The most common cause of knee pain was sports-related activities (64 knees). Other causes included falling from a moving bicycle (5 knees), while knee pain appeared with no defined reason in 14 knees. The most frequent final diagnosis based on knee arthroscopic findings was anterior cruciate ligament (ACL) injury (35 knees), followed by discoid lateral meniscus (16 knees), lateral meniscal tear (11 knees), and medial plica syndrome (9 knees), while no arthroscopic abnormality was observed in 8 of 95 knees. Among the 95 knees, the diagnosis based on preoperative physical tests and imaging findings was different from the arthroscopic diagnosis in 16 knees, 8 of which were diagnosed preoperatively as medial meniscal tear.

Conclusion

ACL injury and discoid lateral meniscus were the predominant conditions in pediatric patients who underwent knee arthroscopic surgery for knee pain. Knee arthroscopy is useful to provide a definitive diagnosis for knee pain in pediatric patients. Preoperative evaluations had a diagnostic accuracy of only 83.2 % and failed to diagnose conditions such as medial plica syndrome and chondral injury. Therefore, diagnosis before knee arthroscopy has to be interpreted with caution.     

Adjuvant chemotherapy for prevention of recurrence of invasive hepatocellular carcinoma after orthotopic liver transplantation

Orthotopic liver transplantation (OLT) is the best treatment for nonresectable hepatocellular carcinoma (HCC), but tumor recurrence reduces long-term and medium-term survival. The effectiveness of adjuvant chemotherapy to prevent tumor recurrence has not been fully established. METHODS: Three hundred eighty-seven consecutive patients, including 43 with HCC superimposed on liver cirrhosis, underwent OLT. Twelve patients with one or more prognostic criteria for HCC recurrence were entered into a prospective prophylaxis protocol with monthly cycles of cisplatin (60 mg/m(2)) and adriamycin (30 mg/m(2)), beginning the fourth week post-OLT for a maximum of seven sessions. RESULTS: The 5-year survival of the non-HCC patients was 65.7% and that of the HCC patients was 60.46% (P = NS). Chemotherapy was reasonably well tolerated, but the 9 patients with hepatitis C- or B-associated cirrhosis showed viral and histological recurrence of the primary disease. A high proportion of patients (7 of 12) developed tumor recurrence during the first year after OLT. Six of these patients died, all but one due to HCC relapse. Five patients remain healthy and tumor free at 58 to 130 months. Post-OLT adjuvant chemotherapy does not avoid tumor recurrence and its fatal consequences but may contribute to prolonged tumor-free survival among a significant proportion of patients with high-risk HCC. However, the uncertain implications on viral recurrence and the lack of control groups do not allow post-OLT chemotherapy to be recommended outside controlled clinical trials, which are clearly warranted.     

A rare cause of acromegaly: Ectopic production of growth hormone-releasing factor by a bronchial carcinoid tumor

Ectopic production of growth hormone-releasing factor (GRF) is a rare cause of acromegaly. In addition to its production by gangliocytomas, both hypothalamic and intrasellar, in rare cases various neuroendocrine neoplasms produce the substance, with resultant growth hormone cell hyperplasia of the pituitary and acromegaly. We report an endocrinologically well-documented case of a GRF-producing bronchial carcinoid tumor in which the associated acromegaly was cured by lobectomy.