Mutations in LZTR1 drive human disease by dysregulating RAS ubiquitination.

The leucine zipper-like transcriptional regulator 1 (LZTR1) protein, an adaptor for cullin 3 (CUL3) ubiquitin ligase complex, is implicated in human disease, yet its mechanism of action remains unknown. We found that Lztr1 haploinsufficiency in mice recapitulates Noonan syndrome phenotypes, whereas LZTR1 loss in Schwann cells drives dedifferentiation and proliferation. By trapping LZTR1 complexes from intact mammalian cells, we identified the guanosine triphosphatase RAS as a substrate for the LZTR1-CUL3 complex. Ubiquitome analysis showed that loss of Lztr1 abrogated Ras ubiquitination at lysine-170. LZTR1-mediated ubiquitination inhibited RAS signaling by attenuating its association with the membrane. Disease-associated LZTR1 mutations disrupted either LZTR1-CUL3 complex formation or its interaction with RAS proteins. RAS regulation by LZTR1-mediated ubiquitination provides an explanation for the role of LZTR1 in human disease.

Inactivation of human coagulation factor X by a protease of the pathogen Capnocytophaga canimorsus.

Essentials Capnocytophaga canimorsus causes severe dog bite related blood stream infections. We investigated if C. canimorsus contributes to bleeding abnormalities during infection. The C. canimorsus protease CcDPP7 causes factor X dysfunction by N-terminal cleavage. CcDPP7 inhibits coagulation in vivo, which could promote immune evasion and trigger hemorrhage. SUMMARY: Background Capnocytophaga canimorsus is a Gram-negative bacterium that is present in the oral flora of dogs and causes fulminant sepsis in humans who have been bitten, licked, or scratched. In patients, bleeding abnormalities, such as petechiae, purpura fulminans, or disseminated intravascular coagulation (DIC), occur frequently. Objective To investigate whether C. canimorsus could actively contribute to these bleeding abnormalities. Methods Calibrated automated thrombogram and clotting time assays were performed to assess the anticoagulant activity of C. canimorsus 5 (Cc5), a strain isolated from a fatal human infection. Clotting factor activities were measured with factor-deficient plasma. Factor X cleavage was monitored with the radiolabeled zymogen and western blotting. Mutagenesis of Cc5 genes encoding putative serine proteases was performed to identify the protease that cleaves FX. Protein purification was performed with affinity chromatography. Edman degradation allowed the detection of N-terminal cleavage of FX. Tail bleeding times were measured in mice. Results We found that Cc5 inhibited thrombin generation and increased the prothrombin time and the activated partial thromboplastin time of human plasma via FX cleavage. A mutant that was unable to synthesize a type 7 dipeptidyl peptidase (DPP7) of the S46 serine protease family failed to proteolyse FX. The purified protease (CcDPP7) cleaved FX heavy and light chains from the N-terminus, and was active in vivo after intravenous injection. Conclusions This is, to our knowledge, the first study demonstrating a detailed mechanism for FX inactivation by a bacterial protease, and it is the first functional study associating DPP7 proteases with a potentially pathogenic outcome.

Emergency medicine resident patient care documentation using a hand-held computerized device.

OBJECTIVE: To determine whether emergency medicine (EM) resident documentation of procedures, patient encounters, and patient follow-ups improved after implementation of a personal digital assistant (PDA) hand-held recording system. METHODS: All first-year EM residents were provided a PalmV (Palm, Inc., Santa Clara, CA) PDA. A customized patient procedure and encounter program was constructed using Pendragon Forms (Pendragon Software Corporation, Libertyville, IL) and loaded into each PDA. Residents were instructed to enter information on patients who had any of 21 procedures performed or were considered to be clinically unstable. These data were downloaded to the residency coordinator's desktop computer. The mean number of procedures, encounters, and follow-ups performed per resident were then compared with those of a group of 36 historical controls from the three previous first-year resident classes who recorded the same information using a handwritten card system. Data from the historical controls were combined and the means of each group were compared by Student's t-test. RESULTS: Mean documentation of three procedures was significantly increased in the PDA group versus the index card system: conscious sedation 5.8 vs. 0.03 (p < 0.000005), thoracentesis 2.2 vs. 0.0 (p = 0.002), ultrasound 6.3 vs. 0.0 (p = 0.002). The mean numbers of pericardiocenteses and unstable pediatric surgical patient evaluations were significantly decreased in the hand-held group [from 1.2 to 0.4 (p = 0.03) and from 9.1 to 2.2 (p = 0.02), respectively]. Patient follow-up documentations were not statistically different between the two groups. CONCLUSIONS: Use of a hand-held PDA was associated with an increase in first-year EM resident documentation in three of 20 procedures and a decrease in one procedure and the number of unstable surgical pediatric patient resuscitations. The overall time savings in constructing a resident procedure database, as well as the other uses of the PDAs, may make transition to a hand-held computer-based procedure log an attractive option for EM residencies.

"Preconditioning at a distance" in the isolated rabbit heart.

OBJECTIVE: Brief myocardial ischemia evokes a cardioprotective response, referred to as "ischemic preconditioning" (IP), that limits injury caused by a subsequent prolonged ischemic insult. The myocardial IP effect can be induced by ischemia of "distant" cardiac and noncardiac tissue, implicating the involvement of an as-yet-unidentified humoral trigger. If a preconditioning hormone exists, the authors hypothesize that the IP effect should be transferable, via administration of coronary effluent, from a preconditioned donor heart to a virgin non-preconditioned acceptor heart. METHODS: Isolated buffer-perfused rabbit hearts were assigned to one of four treatment groups in a donor/acceptor sequence. Donor hearts underwent either three IP cycles or a matched period of uninterrupted perfusion (control donors). Coronary perfusate collected from IP and control donor hearts was reoxygenated and transfused to virgin acceptor hearts. All hearts then underwent 30 minutes of global ischemia followed by 30 minutes of reperfusion. Left ventricular developed pressure (LVDP) (the authors' index of cardioprotection) was monitored throughout the protocol by a left ventricular (LV) balloon. RESULTS: In donor controls, LVDP assessed at 30 minutes post-reflow was restored to only 49 +/- 5% of baseline values. Recovery of LV function was significantly enhanced in both IP donor hearts (69 +/- 4%*) and IP acceptor hearts (70 +/- 6%*) vs donor controls (*p < 0.05), while, in acceptor controls, intermediate values of LVDP (62 +/- 7%) were obtained. CONCLUSION: The IP effect can be transferred between rabbit hearts, suggesting the presence of a humoral trigger signal for distant preconditioning. Isolating this hormone may have therapeutic and diagnostic implications in the management of acute myocardial ischemia.

Core rewarming via warm lavage liquid ventilation in a swine model of hypothermia-associated ventricular fibrillation.

OBJECTIVES: To determine whether warm lavage liquid ventilation (LV) would provide rapid cardiopulmonary rewarming in swine with severe hypothermia and ventricular fibrillation. METHODS: Intubated common swine (n = 3; mean +/- SEM weight 26+/-1.2 kg) were cooled to a mean aortic temperature of 26.4+/-0.9 degrees C. Ventricular fibrillation was induced by transthoracic electrical shock. Rewarming was initiated by continuous endotracheal instillation of warm (44 degrees C) pre-oxygenated, perfluorocarbon liquid at 5 mL/kg/min. Endotracheal instillation of perfluorocarbon occurred while standard gas ventilation continued. Manual chest compressions were performed throughout the 30-minute rewarming process. Outcome measures were the absolute and relative rates of change of all temperatures. RESULTS: After 30 minutes of warm lavage LV, the mean aortic and pulmonary artery temperatures increased by 6.6+/-0.6 degrees C, respectively. Esophageal, nasal, and rectal temperatures did not change significantly. In one animal, normal sinus rhythm spontaneously returned after 16 minutes of rewarming. CONCLUSIONS: During cardiac arrest, warm lavage liquid ventilation may produce rapid cardiopulmonary rewarming.

Rapid development of brain hypothermia using femoral-carotid bypass.

OBJECTIVES: Advances in the field of cardiopulmonary resuscitation have led to an increasing number of patients initially surviving sudden cardiac arrest. Unfortunately, most of these patients do not recover from the resultant anoxic brain insult. Several animal and human trials have suggested that post-resuscitative brain hypothermia may improve neurologic recovery after cardiopulmonary arrest. Present cooling methods are slow, induce only brain surface cooling, or result in systemic hypothermia. The authors tested the hypothesis that unilateral hypothermic carotid bypass would induce bilateral brain cooling without evoking systemic hypothermia or hemodynamic instability. METHODS: Anesthetized, ventilated common swine (n = 6, 24-37 kg) underwent right femoral and carotid artery bypass cannulation. Central and peripheral hemodynamic parameters were recorded every 2 minutes throughout the procedure. Thermodynamic parameters included bilateral frontal lobe, bilateral nasopharyngeal, pulmonary artery, and rectal temperatures. Hypothermic femoral-carotid bypass was accomplished by drawing blood from the right femoral artery, cooling it to 24 degrees C, and returning it to the right carotid artery at a flow rate of 5 mL/kg/min for 30 minutes. RESULTS: With initiation of cooling, brain temperatures dropped rapidly from baseline of 37.2 degrees C to 30.6 degrees C (right frontal lobe) and 33.1 degrees C (left frontal lobe) at 30 minutes. Pulmonary artery and rectal temperatures also decreased, but never reached mild hypothermic levels (34 degrees C). There was no significant change in any hemodynamic parameters during brain cooling. CONCLUSIONS: Femoral-carotid hypothermic bypass rapidly induced a state of selective brain hypothermia without causing systemic hypothermia or hemodynamic instability.

The use of neuromuscular blocking agents in the emergency department to facilitate tracheal intubation in the trauma patient: help or hindrance?

PURPOSE: The purpose of this study is to examine the relationship between the occurrence of a difficult intubation and (1) the use of neuromuscular blocking agents (NMB) and (2) the presence of airway injuries. It is a retrospective analysis of data from a trauma registry. MATERIALS AND METHODS: Registry records of patients (n = 160) who required emergent endotracheal intubation or establishment of a surgical airway over a 3.5-year period in the emergency department were reviewed. Risk factors for difficult intubations were identified and analyzed using multivariate logistic regression analysis. RESULTS: NMB were used in 75% of patients requiring intubation. Fifteen percent of the intubations were considered difficult. No association was found between the presence of airway injuries and difficult intubations; however, the use of succinylcholine was associated with a lower risk of difficult intubations compared with intubations where a nondepolarizing NMB was used. CONCLUSIONS: The use of succinylcholine may result in fewer difficult intubations in the trauma patient than when a nondepolarizing NMB is used. The presence of airway injuries did not appear to predispose to difficult intubations.

A retrospective study on the efficacy of short-term perioperative prophylaxis in abdominal surgery for hernia repair in 1,254 patients.

Between 1992 and 1999 1,254 patients requiring hernioplasty came to our Department of Surgery, at San Giovanni Valdarno Hospital, Arezzo. In 94% of cases a prosthetic device was inserted. All patients received a preoperative antibiotic prophylaxis with ceftriaxone, administered intravenously in a single 2 g dose, before surgery. We have retrospectively evaluated the incidence of postoperative infections in these patients: no surgical wound infection occurred, while we observed 10 cases of systemic infections, 5 respiratory tract infections and 5 urinary tract infections, all of which were successfully treated with antibiotics. Tolerability was good: no adverse reaction to ceftriaxone was observed. In this retrospective study ceftriaxone was shown to be effective in preventing the onset of postoperative infections.

Management of human papilloma virus vulvo-perineal infection with systemic beta-interferon and thymostimulin in HIV-positive patients.

OBJECTIVES: To evaluate the effect of a combined therapy based on beta-interferon and thymostimulin in HIV-seropositive women with florid vulvoperineal condylomatosis. METHODS: Nineteen HIV-seropositive women affected by HPV florid vulvo-perineal infection were studied. Their ages ranged from 19 to 32 years (mean = 26); all were smokers; 11 (57.89%) were intravenous drug users with a mean period of drug addiction of 5 years. No patient was on AZT therapy. All patients underwent a combined medical therapy based on beta-interferon administration with doses of 3,000,000 IU i.m. daily for 7 days and subsequently on alternate days for 2 weeks associated with the administration of 70 mg i.m. of thymostimulin per day on alternate days for 30 days. RESULTS: Seven (36.84%) patients showed complete recovery at the end of follow-up; 5 (26.31%) patients showed partial recovery and 7 (36.84%) did not respond to therapy. CONCLUSION: A pro-host immunotherapy seems to be indicated in patients affected by immunodeficiency syndrome.

Cervical intraepithelial neoplasia: carbon dioxide laser vaporization and conization. Our experience.

Between 1984 and 1992, the CO2 laser was used to treat 341 patients affected by CIN of various degrees. On the basis of specific indications these patients underwent vaporization or conization. Two hundred and twenty eight patients underwent vaporization of intraepithelial lesions, 221 (96.92%) of whom were free of disease after one laser treatment, as observed during the subsequent years of follow-up. In 105 out of the 113 patients treated with conization the cone margin was free of disease. One hundred and one (96.19%) of the these 105 patients had no evidence of disease after one year of follow-up. In the remaining 8 (7.07%) cases examination of the cone revealed the presence of invasive carcinoma. The major complication was vaginal discharge observed in 115 (33.72%) patients. The CO2 laser is a very effective therapeutic procedure for the treatment of intraepithelial lesions of the cervix and permits to preserve reproductive function and anatomic integrity.

[Blue nevus of the endocervix]. / Nevo blu dell'endocervice.

We report a case of blue nevus of the uterine cervix discovered in a cone removed for other reasons. The lesion can be interpreted as a visceral analogue of the cutaneous blue nevus. Histological and Immunohistological studies suggest the melanocytic nature of the lesion.

[Laser CO2: results of treatment of HPV lesions in male the partner]. / Laser CO2: risultati del trattamento delle lesioni virali da HPV nel partner maschile.

Hundred-fifty-seven male partners of patients affected by Human Papillomavirus (HPV) lesions, underwent CO2 Laser vaporization between January 1989 and January 1990. The age ranged between 18 and 45 (median 28.2). The vaporization was performed with a Coherent System 451 CO2 Laser equipment, at a power of 16 watt in continuous mode, depth of 2 mm and a free margin of 2 mm. First Laser treatment proved successful in 129 patients (82.1%); 17 out of 28 patients with persistent or relapsed pathology underwent a second CO2 Laser vaporization with a total cure percentage equal to 92.9%. Laser-surgery is the method of choice in the treatment of HPV genital lesions.

[Colpo-cyto-histological correlations in intraepithelial lesions of the uterine cervix]. / La correlazione colpo-cito-istologica nelle lesioni intraepiteliali della cervice uterina.

The aim of this study was to assess the clinical efficiency of colposcopic findings as diagnostic tests for intraepithelial lesion using the analysis of colpo-cyto-histological correlations. The results of 3340 colposcopic tests performed in the Colposcopy Unit of the Second Clinic of Obstetrics and Gynecology between March 1990 and May 1991 were analysed, taking into account 326 (9.7%) cases of Abnormal Transformation Zone (ANTZ). The colpo-histological correlation in ANTZ 1 cases (52 cases of white epithelium, 92 standard mosaic, 42 standard dotted and 61 mixed cases) was 65.2% (52.3%) for HPV; 12.9% for CIN). The colpo-histological correlation in ANTZ 2 cases (30 cases of thickened white epithelium, 5 irregular mosaic, 4 irregular dotted, 2 atypical vessels, 4 thickened gland outlets and 6 mixed cases) was 70.5% (43.3% for HPV; 27.2% for CIN an and Ca). In this retrospective study colposcopy showed a diagnostic accuracy of 64.6% in the cases examined and played a decisive role in the diagnosis of intraepithelial lesions of the uterine cervix.

Persistent vulvovaginal candidiasis: systemic treatment with oral fluconazole.

52 patients affected by persistent vulvovaginal candidiasis underwent systemic therapy with oral Fluconazole at a dose of 150 mg once a week for 3 weeks. 31 (59.61%) patients were cured at the first control after therapy. Of the remaining 21 patients, 4 (7.69%) were lost at follow-up and 17 (32.69%) underwent a second cycle of systemic therapy with complete recovery confirmed at the further controls. The overall percentage of recoveries was equal to 92.30%. The results suggest that Fluconazole is very effective in mycotic vulvovaginitis with irrelevant side effects.

Vulvar and penile HPV lesions: laser surgery and topic anaesthesia.

Treatment of genital warts (HPV lesions) by Laser-surgery was performed in 90 patients and 90 male partners under topical anaesthesia with 1-3 gr EMLA cream and in 45 patients and 45 males (control groups) under 1-2 ml 2% Carbocaine infiltration. EMLA cream was applied to warts 5-18 minutes (median = 7) before operation. Pain from application of anaesthetic and Laser surgery was significantly less (p < .001) in the groups treated by EMLA. Side effects were minimal in the EMLA groups. The results suggest that EMLA cream could be the anaesthetic of choice in Laser surgery of genital warts.

Topic and systemic administration of natural alfa interferon in the treatment of female and male HPV genital infections.

The aim of the study was to evaluate the effectiveness and tolerance of topic and systemic administration of natural alfa-interferon from normal human leukocytes in the treatment of HPV lesions of the lower genital tract. From May 1991 through May 1992, 70 women (mean age = 29; range 16-42) and 51 men (mean age = 28; range 18-48) with histologically proven HPV genital lesions were studied. 43 patients and 32 male partners with subclinical infection underwent cream therapy (4 applications/day for 30 days) composed of natural alfa interferon and containing 1,000,000 IU/gr. 27 women and 19 men affected by florid infection underwent systemic i.m. therapy with natural alfa interferon in doses of 3,000,000 IU on alternate days for 30 days. The percentage of therapeutical success amounted to 55.8% for women and 78.1% for men subjected to topic therapy; for the 27 patients and 19 male partners treated with systemic therapy the final percentages of success were 70.3% respectively. Natural alfa interferon from normal human leucocytes seems to be a drug of good efficacy and tolerance in the treatment of HPV genital pathology.

Pain evaluation during carbon dioxide laser vaporization for cervical intraepithelial neoplasia: a randomized trial.

63 pts affected by CIN of various degrees were randomly divided into 3 groups in order to evaluate the pain experienced during laser vaporization of the lesion. All pts were premenopausal and ages ranged between 19 and 39 years. 21 pts received Naproxene Sodium (550 mg) 30 minutes before surgery; 21 pts received placebo and 21 pts received no drug. Laser vaporization was performed with a Coherent System 451 CO2 laser with a power setting of 28 W/cm2 and a spot size of 1.8 mm. The severity of pain was assessed by means of a Visual Analogue Scale. The mean VAS value was 19 for the group treated with Naproxene Sodium; the mean VAS value was 20 for the placebo group and 23 for the group which received no pre-operative drug. Analysis of data from the 3 groups showed no statistically significant difference. Analgesia or anaesthesia before laser surgery for CIN is not a necessity.

[The solitary rectal ulcer today. A review of the literature]. / L'ulcera solitaria del retto oggi. Revisione della letteratura.

The solitary rectal ulcer (SRU) is a benign lesion of adults of either sex, which presents with chronic constipation, peculiar defecatory disorders, rectal prolapse and smaller psychological abnormalities. The characteristic appearance of this disease is a "neither being always ulcerate, nor always solitary" lesion, but often with polypoid or granular feature, typically localized in anterior rectal wall, a few inches from anal channel. Distinctive histopathological specimens are localized mucosal distortion, hypertrophic proliferation of muscularis mucosae and obliteration of lamina propria by fibroblasts and muscle fibres from the muscularis mucosae. Very few intermittent or recurrent symptoms are rectal bleeding and mucous discharge with defecations, difficulty of a complete ampullar evacuation and sometimes pelvic or rectoperineal pain. Clinical picture and endoscopic biopsies led to diagnosis. Barium enema, defecography, transrectal ultrasound, manometry and electromyography have an additional role. Medical treatment is performed by high-fiber diet, but biofeedback training is very helpful. Surgical management is as an excisional surgery, as a rectopexy if there is prolapse. Fecal diversion and rectocolic resection are considered only for patients with obstinate and severe symptoms. Even in patients who seem to advocate a surgical approach it is important to heal a dyskinetic puborectalis muscle.