Close relationship between motor impairments and loss of functional motoneurons in a Charcot-Marie-Tooth type 1A model

Charcot-Marie-Tooth disease type 1A is the most frequent hereditary neuropathy affecting the peripheral nervous system. A partial duplication of chromosome 17 (17p11.2) involving the PMP22 gene is responsible for dysmyelination-demyelination processes leading to motor and sensory impairments.Murine models of this disease are now widely used to investigate the mechanisms occurring at the behavioural and physiological levels. In this study, adult transgenic mice (6 months old) having integrated 7 copies of the human PMP22 gene were used to compare the motor performance, evaluated by using a complex locomotor test (the rotarod test), with both the number of functional motoneurons innervating the soleus muscle and the level of myelination in the sciatic nerve. Two levels of motor deficits were detected and led us to divide the population into two subgroups.In both impaired groups, the level of motor deficit was strongly correlated with the number of functional motoneurons evaluated by retrograde labeling from the muscle, but not with the number of myelinated fibers or the thickness of the myelin sheath (g-ratio). It therefore appears that the number of motor units may be a key element in motor impairments observed in Charcot-Marie-Tooth disease type 1A disease. These findings may have implications for therapeutic procedures, which should focus on the survival of the motoneuronal pool and/or the maintenance of functional neuro-muscular connexions to reduce motor impairments in humans.     

Carbamazepine poisoning: treatment with haemodialysis.

Sir, A 32-year-old woman was brought to the emergency room 28 h afteringesting an unknown amount of carbamazepine (probably 150–200tablets containing 200 mg each). She had been taking cabamazepine400 mg twice daily for the past 10 years for symptomatic epilepsyrelated to cerebral arterio-venous malformation. She was unconsciousbut responding to noxious stimuli. She had shallow irregularrespiration     

Comparing resident measurements to attending surgeon self-perceptions of surgical educators

OBJECTIVE: The purpose of this study was to evaluate the initiation and utility of evaluating attending surgeons as educators by resident trainees. Additionally, we were interested in comparing resident measurements to attending self-perceptions. METHODS: A written evaluation form, (utilizing five-point ordinal scale assignments) queried respondents regarding the performance of surgical attendings in the operating room, and other clinical settings. A similar form was distributed to the faculty members, which they used to evaluate themselves. Mean scores were determined, as were comparisons between self-perception and resident assessments. Differences in scores with p values less than 0.05 were considered statistically significant. RESULTS: Thirty-six residents evaluated 23 attendings. Mean assignments by residents of performance in the operating room, other clinical settings, and overall scores for all faculty members as a group were 4.22 +/- 0.04, 4.11 +/- 0.03, and 4.16 +/- 0.03, respectively, with a score of five, generally corresponding to a most favorable rating. When overall scores were analyzed, 10 attendings received scores that differed significantly from those received by their peers, with half of subjects above, and the other half being below the 95% confidence interval. Eighteen (78%) of attendings completed the self-evaluation forms, and of these, 11 (61%) had self-perceptions that differed significantly from overall scores as reported by the residents. CONCLUSIONS: Our evaluation process delineated significant differences among attending faculty members and identified individual strengths and weaknesses. Many educators' self-perceptions differed significantly from resident assessments, and attendings who did not evaluate themselves scored lower than their peers.     

Laparoscopic sigmoidopexy by extraperitonealization of sigmoid colon for sigmoid volvulus: two cases

Sigmoid colectomy-open or laparoscopic-has been advocated as the treatment of sigmoid volvulus. This has a higher incidence of morbidity and mortality. We have successfully treated 2 cases of recurrent sigmoid colon volvulus with laparoscopic sigmoidopexy by extraperitonealization of the sigmoid colon. Laparoscopic sigmoidopexy by this technique has not been reported before. The first patient was a 20-year-old male and the second was a 72-year-old female. In both patients, initial detorsion of volvulus was achieved by rectal tube. As the colon was nongangrenous, elective laparoscopic sigmoidopexy by extraperitonealization of the sigmoid colon was performed 4 days after the detortion. Operative times were 50 minutes and 70 minutes. Both patients were discharged from the hospital on the third postoperative day. There has been no recurrence of volvulus over a period of 6 and 7 months. There were no complications. In conclusion, laparoscopic sigmoidopexy by extraperitonealization of the sigmoid colon may become a superior alternative for the treatment of sigmoid volvulus with nongangrenous colon.     

Rapid imipenem/cilastatin desensitization for multidrug-resistant Acinetobacter pneumonia

OBJECTIVE: To report a successful case of rapid imipenem desensitization in a critically ill patient with multidrug-resistant Acinetobacter baumannii ventilator-associated pnemonia (VAP). CASE SUMMARY: A 40-year-old white man who had a lengthy stay in the intensive care unit (ICU) following a motorcycle accident developed VAP caused by A. baumannii. treatment with imipenem was necessary due to the bacteria's resistance to all other antibiotics. However, this patient was diagnosed with an allergy to imipenem following exposure earlier in his hospitalization in addition to a positive penicillin skin test. Thus, we attempted rapid desensitization to imipenem using a continuous infusion protocol. The patient was desensitized within 4 hours and was successfully treated for 21 days with a continuous infusion of imipenem combined with daily amikacin. He experienced no adverse reaction during the desensitization process or the remainder of his treatment course. DISCUSSION: The protocol used in this case was modified from a previously reported case, and differed in the speed of desensitization and total daily dose. We assumed that a more gradual escalation of the dose in our modified protocol would prevent the occurrence of adverse events, thereby resulting in more rapid desensitization. Rapid desensitization was necessary in this patient due to the presence of a life-threatening infection. The lower total daily dose of imipenem was in response to impaired renal function. CONCLUSIONS: Therapeutic options for multidrug-resistant pneumonia in the ICU are significantly limited in the presence of imipenem allergy. An option of last resort is to desensitize the patient using a rapid administration protocol. Our modified rapid imipenem desensitization protocol was successful and allowed for effective treatment of life-threatening pneumonia.