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M Negri

Publications and source records attributed to M Negri.

At least 19 recordsLinked to original sources
PubMed2006

The microbial degradation of azimsulfuron and its effect on the soil bacterial community.

AIMS: Azimsulfuron is a recently introduced sulfonylurea herbicide useful in controlling weeds in paddy fields. To date very little information is available on the biodegradation of this pesticide and on its effect on the soil microbial community. The aim of this work was to study its biodegradation both in slurry soil microcosms and in batch tests with mixed and pure cultures. METHODS AND RESULTS: Azimsulfuron was applied to forest bulk soil in order to study its effect on the structure of the bacterial soil community, as detectable by denaturant gradient gel electrophoresis (DGGE) analyses. Biodegradation and abiotic processes were investigated by HPLC analyses. In addition, a microbial consortium was selected, that was able to use azimsulfuron as the sole energy and carbon source. One of the metabolites produced by the consortium was isolated and identified through LC-MS analyses. Cultivable bacteria of the consortium were isolated and identified by 16S rDNA sequencing (1400 bp). CONCLUSIONS: Azimsulfuron treatment seems to have the ability to cause changes in the bacterial community structure that are detectable by DGGE analyses. It is easily biodegraded both in microcosms and in batch tests, with the formation of an intermediate that was identified as 2-methyl-4-(2-methyl-2H-tetrazol-5-yl)-2H-pyrazole-3-sulfonamide. SIGNIFICANCE AND IMPACT OF THE STUDY: The study increases the knowledge on the biodegradation of azimsulfuron and its effects on the soil microbiota.

Bacteria↗
PubMed2004

[Refreshing in abdominal ultrasonography--a summary from SGUM Kongress Davos in 2003].

Ultrasonography is a modern noninvasive imaging technique with a high resolution, and high evidence in diagnostic questions, high acceptance in patients, low costs and no side effects. There are pure questions in whitch the diagnostic ultrasound is not able to give a satisfactory answer. Important is basically a well trained examinator with long experience and an exact examination and documentation.

Abdomen↗
PubMed2003

[The value of ultrasound diagnosis in "acute appendicitis" patient admission].

UNLABELLED: The rate of unnecessary appendectomy is frequently criticized. Today, sonography and CT-scan are helpful tools to minimize this rate. Which value has the ultrasonography in the decision making today? METHODS: Retrospective analysis of 132 patients undergoing appendectomy in respect of sonography and rate of histologically confirmed appendicitis from 1.1.95-31.12.98. Prospective analysis of 99 patients admitted for acute appendicitis in respect of pre- and posttest-probability (after sonography) by the responsible surgeon from 1.1.99-31.12.00. RESULTS: Retrospective part: 122/132 patients had an acute appendicitis (92%). Sonography was performed in 64% of the patients. There was only one wrongly positive sonography. Prospective part: 76/99 patients were operated on. 70/76 had an acute appendicitis (92%). Sonography was performed in 87%. Six patients presented a histologically normal appendix: In two of them no increase of the probability after sonography was noted, in three of them an slight increase of only 20%, and in one of them a decrease of 20% even. CONCLUSION: Sonography with a pre- and posttest-probability is recommended in clinically doubtful cases. In our experience the physician performing the sonography is almost always right. But the diagnosis of an acute appendicitis remains a combination of clinical and sonographic evaluation.

Acute Disease↗
PubMed2002

[Interdisciplinary complications conference--also a (simple) kind of quality assurance].

Documentation of complications is a "must" today. Several societies have been formed and several systems of documentation exist to fulfill these requirements. But there are also very simple tools for quality management in every hospital. Since 1995 all surgical/orthopedic interventions have been prospectively recorded at the hospital of Frutigen. Every other month a list of all operations and their complications is put together by the two surgeons-in-chief. This list is then presented at the so-called interdisciplinary complications-conference. This meeting is open to all employees of the hospital and to all medical doctors of the region. From the 1st January 1995 to the 31st December 2001 7396 surgical interventions were performed on in- or outpatients. 134 complications (1.8%) occurred. These were: 49/7396 infections (0.7%), 14/1395 re-osteosyntheses (1%), 21/7396 hematomas requiring evacuation (0.3%), 8/7396 disturbances in wound healing (0.1%) and 42 other, postoperative complications. Postoperative infection occurred most frequently after appendectomies 10/251 (4%), the rate after internal fixation was 0.6% (9/1395). Hematomas were encountered most frequently after total joint replacement (hip and knee) 4/180 (2.2%), followed by inguinal hernias 4/287 (1.4%). The rate of re-osteosynthesis was highest after internal fixation of proximal humerus fractures 5/58 (8.6%). This systematic documentation of complications allows an analysis of the operative/perioperative management. By introducing specific measures (compression-bandage after operations of inguinal hernias and total hip prosthesis, new implant with rotational stability for proximal humerus fractures) an attempt can be made to reduce the rate of the most frequent complications. The public presentation of the complications at the meeting makes it possible to communicate good and bad results to the whole staff including the general practitioners, and the interdisciplinary mode of discussion permits the inclusion of not only the surgical but also all other possible aspects of the treatment of the patients.

Cross-Sectional Studies↗
PubMed2001

Met-enkephalin levels during PTCA-induced myocardial ischemia.

Met-enkephalin (Met-enk) has been demonstrated to modulate myocardial-ischemia mechanisms via the opioid receptors, but no studies are now available on Met-enk levels in the coronary circulation. In this experience Met-enk levels were evaluated in aortic root and in coronary sinus at baseline (T0), during PTCA induced transient ischemia (T1) and during reperfusion (T2). No significant differences were found at any time. Thus, it appears that there is no Met-enk extraction from the coronary circulation during provoked myocardial ischemia and no Met-enk release from the ischemic heart.

Aged↗
PubMed2001

Neoplastic disease after heart transplantation: single center experience.

OBJECTIVES: Mandatory use of prolonged immunosuppression in organ transplantation is complicated by an increased incidence of cancer. The current study represents a retrospective analysis of the incidence of neoplasms in our heart transplantation program. METHODS: Four-hundred and seventy-four patients (403 male and 71 female; mean age, 48.6+/-12.1 years), with at least 30 days of follow-up, were enrolled in this study. Patients received triple immunosuppression with cyclosporin A, azathioprine and steroids. Moreover, as a prophylactic anti-lymphocyte therapy, 388 patients (82%) were administered RATG, 67 patients (14%) received ALG and 19 patients (4%) OKT3. The mean follow-up time was 71.1+/-43.0 months. RESULTS: Fifty-five patients (11.6%) developed malignant neoplasms. The cancer frequencies were: solid tumors, 55%; non-Hodgkin lymphomas (NHL), 20%; Kaposi's sarcomas, 11%; skin cancers, 9%; undifferentiated sarcomas and myelomas, 5%. Solid tumors mainly affected the lung (39%), bowel (16%), stomach (6.5%), liver (6.5%), pancreas (6.5%) and oral cavity (6.5%). The times to the onset of cancer from transplantation were: Kaposi's sarcoma, 12.7+/-16.8 months; skin cancers, 34.5+/-23.8 months; solid tumors, 54.3+/-38.7 months; NHL, 60.1+/-36.4 months; undifferentiated sarcomas and myelomas, 90.0+/-15.6 months. As determined by univariate and multivariate analyses, sex, number of treated rejections, previous history of tumor, average dose of cyclosporine and prednisone and cyclosporine blood levels did not increase the incidence of malignancies. Univariate analysis suggests a significant correlation between the type of prophylactic immunoglobulins and the average dose of azathioprine with the incidence of neoplasms. Both univariate and multivariate analyses demonstrated a significant correlation between patient's age at the time of transplantation and risk of cancer occurrence (risk increased by 1.074/year; P=0.0056 with multivariate Cox regression). CONCLUSIONS: Cancer is a strong limitation for long-term survival after heart transplantation. The only risk factor recognized is the patient's age at the time of transplant. Furthermore, the type of prophylactic globulins used for induction therapy and some specific immunosuppressant agent (azathioprine) may play a significant role in the development of malignancies after transplantation.

Adult↗
PubMed2001

The role of met-enkephalin in silent myocardial ischemia in diabetic patients.

Met-enkephalin plasma levels were evaluated in 20 cardioischemic diabetic patients. All the patients had ECG ischemic signs. Ten patients with diabetic autonomic neuropathy, experienced no pain during myocarial ischemia. Met-enkephalin levels in the diabetic patients with silent myiocardial ischemia were significantly lower compared to those in the symptomatic patients. This demonstrates that the absence of myocardial ischemic pain in neuropathic diabetic patients is not accounted for by met-enkephalin action.

Adult↗
PubMed2000

High serum levels of secretory immunoglobullin A in chronic pancreatitis.

BACKGROUND AND AIM: Elevated levels of secretory immunoglobulin A have been reported in patients with cholestatic hepatitis. Secretory immunoglobulin A is present in the biliary and pancreatic tract. Chronic pancreatitis is a disease characterized by dilatation of Wirsung's duct. The aim of the study was to evaluate secretory immunoglobulin A levels in patients suffering from chronic pancreatitis. PATIENTS AND METHODS: The study population consisted of 66 consecutive chronic pancreatitis patients (55 male, 11 female; mean age 49.6+/-10 years), 26 patients suffering from acute recurrent pancreatitis (9 males, 17 females; mean age 39.6+/-10.6 years) and 90 healthy controls, pair-matched for sex and age with the chronic pancreatitis patients. Secretory immunoglobulin A was determined by enzyme-linked immunosorbent assay, as were serum alanine transaminase and GGT. RESULTS: Secretory immunoglobulin A levels were significantly higher in chronic pancreatitis patients (35+/-23.7 mg/l) than in those acute recurrent pancreatitis group (16.1+/- 7.9) and in healthy controls (11.8+/-4.9 mg/l) (p<0.0001). Secretory immunoglobulin A was significantly higher in chronic pancreatitis patients with steatorrhoea, diabetes and calcifications and in those undergoing pancreatic surgery. Of 61 chronic pancreatitis patients, 14 (23%) had pathological GGT. When only chronic pancreatitis patients with normal GGT levels were analysed, the differences in secretory immunoglobulin A levels between groups of patients and between chronic pancreatitis subgroups remained statistically significant. CONCLUSIONS: This study demonstrates that secretory immunoglobulin A is elevated in chronic pancreatitis. Its value in the staging of patients needs to be further evaluated.

Adult↗
PubMed1999

Diverticulitis: the effect of age and location on the course of disease.

To examine the effect of patient's age and the location of diverticular disease on the course of the acute disease we retrospectively collected demographic data, symptoms, laboratory findings, imaging techniques, type of treatment (conservative vs. surgical), early and late complications, and follow-up data on 119 patients with acute diverticulitis (74 women, 45 men; mean age 64+/-14 years; follow-up 7-102 months, median 40). Patients were divided by their age into two groups (42 aged 60 years or younger, 77 aged over 60) and on the location of their disease (108 to the left of the middle transverse, 11 to the right). Lower abdominal pain, abdominal tenderness, and fever were the most common complaints (70-97%). In the younger patients we found a significantly greater preponderance in the right colon (P = 0.02) than in older patients. Abdominal abscesses and fistulas were more common in right-sided diverticulitis (P = 0.01). Patients with right-sided colon diverticulitis were treated surgically (82%) and on an emergency basis more often than patients with left-side colon diverticulitis (25%; P = 0.001). Older patients treated conservatively suffered more than younger patients (61% and 33% respectively; P = 0.04) from recurrent abdominal pain but not from recurrent, confirmed diverticulitis. Patients with right-sided diverticulitis treated conservatively suffered more from recurrent diverticulitis episodes than patients with left-sided diverticulitis (P = 0.05). Younger patients thus do not have a more aggressive form of diverticulitis than older patients. Patients with acute diverticulitis in the right colon are likely to be operated earlier and for mistaken diagnoses than patients with left-sided diverticulitis.

Adult↗
PubMed1999

Fatal cardiac tamponade as a late complication of central venous catheterization: a case report.

Central venous catheterization is a reliable technique in neonatal surgery. Nevertheless, the rate of mechanical catheter-related complications remains high. We report a neonate with gastroschisis in which the successful placement of a central venous catheter was followed later by a cardiac tamponade with a fatal outcome. This complication occurred without perforation of the cardiac wall. A similar finding has been reported in only one other pediatric patient. Vigilant observation is required in any neonate with a central venous line in place to prevent the occurrence of this life-threatening event.

Cardiac Tamponade↗
PubMed1998

Increased plasma concentration of atrial natriuretic hormone in myotonic dystrophy.

Atrial natriuretic hormone (ANH) concentrations were measured in 16 patients affected with myotonic dystrophy (MyD) undergoing 24-hour Holter ECG and in 15 age-matched normal subjects. Although the MyD patients did not show overt left ventricular function impairment, their plasma ANH levels were found to be higher (183.76 +/- 113.25 pg/ml) compared to those of the control subjects (39.73 +/- 9.95 pg/ml, p < 0.001). Nine patients with arrhythmias and some echocardiographic alterations formed subgroup A. Seven patients without cardiac alterations formed subgroup B. No significant difference in ANH emerged between the two subgroups. This evidence suggests that high plasma ANH levels in MyD cannot always be related to overt or latent heart failure and to arrhythmias.

Adult↗
PubMed1998

External Quality Assessment of stat test intralaboratory turnaround times. Pilot study from the Members of the Working Group for the Standardization and Promotion of Turnaround Time Control under the Auspices of the Comitato Italiano per la Standardizzazione dei Metodi Ematologici e di Laboratorio.

We describe procedures, results and prospects of a pilot program in External Quality Assessment (EQA) of the stat test intralaboratory turnaround times. Our goals are to promote quality by systematic monitoring and comparison of performances by laboratories, continuous investigation into the state of the art of the processes from receipt of sample to transmission of results and creation of a data base for standardization of measures and definition of consensus values for turnaround time. Of 30 laboratories invited to participate, 25 took part, agreeing to record times of arrival and transmission for all determinations of three analytes (blood hemoglobin, serum/plasma potassium and plasma prothrombin time) for seven consecutive days and to continue for one or more further periods of seven days as necessary if there were less than 300 determinations for each analyte. Within a preset time limit, data were sent by e-mail on an Excel file and we sent back two reports per analyte, showing: i) the graph for time vs. percentage of tests completed and several measures of turnaround time; ii) results of all laboratories in graph form, allowing each laboratory to identify only its own data. The high proportion of participating laboratories among those invited (83%) encourages us to implement the EQA program systematically, on a half-yearly basis, extending it to all laboratories wishing to participate in Italy or elsewhere in Europe.

Italy↗
PubMed1998

Plasma atrial natriuretic hormone in hyperthyroidism.

In 22 hyperthyroid patients, atrial natriuretic hormone (ANH) levels (71.91 +/- 21.03 pg/ml), measured during a 3-h-Holter, were found to be significantly higher (p < 0.001) than those in 20 age-matched normal subjects (37.22 +/- 8.73 pg/ml). We have demonstrated that the presence of tachiarrhythmias does not influence ANH release. The positive and significant correlation of FT3 with both ANH and heart rate confirms the hypothesis of a direct action of thyroid hormones on ANH release.

Adult↗
PubMed1998

[Progressive sensorineural hearing loss: neoplastic causes].

Acoustic neuromas represent about 90% of all space-occupying lesions of the cerebellopontine angle and account for approximately 6% of all intracranial tumors. Progressive unilateral sensorineural hearing loss is the most frequent initial symptom occurring in over 90% of patients. A sudden onset of hearing loss occurs in 5%, while 5% of cases present with normal hearing. The incidence of hearing loss does not seem to be related to tumor size. Accuracy of the tumor detection by gadolinium-enhanced magnetic resonance imaging has been reported as 99-100% even for intracanalicular tumors. The ABR false negative rate for intracanalicular tumors has been reported to be as high as 9-11%. Rare lesions of the cerebellopontine angle include: meningiomas, epidermoids, arachnoid cysts, trigeminal nerve neuromas, facial nerve neuromas, neurinomas of lower cranial nerves, glomus tumors and metastases. Therefore, a high suspicion index and awareness of symptoms and an adequate audiologic and neuroradiologic work-up are the clues to early diagnosis and appropriate surgical treatment.

Cerebellar Neoplasms↗
PubMed1998

Coronary sinus plasma beta endorphin levels in cardioischemic patients undergoing PTCA.

Plasma beta-endorphin levels were studied in the coronary sinus of 8 patients undergoing percutaneous transluminal coronary angioplasty (PTCA). All the patients had ECG ischemic signs and pain during the inflation of the balloon. No significant changes in plasma beta-endorphin levels were observed during PTCA-induced ischemia. Baseline coronary sinus plasma beta-endorphin levels were found to be elevated when compared with peripheral ones which would suggest an accumulation of beta-endorphin in the ischemic heart.

Aged↗
PubMed1997

Pulse oxymetry evaluation of oxygen saturation in the upper extremity with an arteriovenous fistula before and during hemodialysis.

We noticed that some patients with arteriovenous (AV) fistula on chronic hemodialysis experience pain in the limb with the fistula a short time after being connected to the dialysis machine. We postulated that the pain is caused by relative ischemia and therefore performed this study to determine whether oxygen saturation (SaO2) of the extremities with AV fistula decreases during hemodialysis. Seventy-two patients with a side-to-side primary AV fistula were evaluated by pulse oxymetry. SaO2 was measured before hemodialysis and 20 minutes after initiation of dialysis. The contralateral arm served as a control. In 48 patients, SaO2 difference between the arms of each patient before hemodialysis was less than 4%. SaO2 values of this group of patients did not change significantly 20 minutes after initiation of dialysis. In 24 patients, SaO2 differences between the hands of each patient before hemodialysis were 4% or more. In this group of patients, SaO2 values of the hands with the AV fistula decreased significantly 20 minutes after hemodialysis from a mean of 90.85 +/- 2.84% to 81.60 +/- 3.94 (P < 0.001). SaO2 remained unchanged in the contralateral arm. Nine patients in this group complained of pain and change in sensation in the arm with the fistula during hemodialysis. One patient complained of severe pain in the arm with the fistula before hemodialysis, and SaO2 was unmeasurable. We conclude that, in some patients, SaO2 of the arm with the AV fistula decreases only during hemodialysis. This phenomenon may be symptomatic. A predialysis SaO2 difference of 4% or more between the arms predicts decreased SaO2 of the arm with the AV fistula during hemodialysis.

Arm↗
PubMed1997

[Intraoperative tonal-threshold audiometry in the surgery of otosclerosis].

At the end of stapedioplasty, performed under local anesthesia, the surgeon usually tests the hearing function making questions to the patient turning his voice from a soft whisper to a loud tone. At the ENT Department, University of Parma Italy, a more precise method is employed in order to measure the air conduction threshold of the patient at the beginning and at the end of surgery. From April 1996 to October 1996, intraoperative pure-tone audiometry was performed in 36 patients who underwent stapedioplasty. A portable audiometer "Amplaid 161/C Amplifon" was used in the operating room. Air conduction thresholds were measured at 125-8000 Hz. Intraoperative pure-tone audiometry allows an instantaneous and a more accurate evaluation of the surgical functional results.

Adult↗