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M Vassallo

Publications and source records attributed to M Vassallo.

At least 19 recordsLinked to original sources
PubMed1998

[Lyme borreliosis, emergent disease linked with the environment].

After a short historical presentation of the discovery of the pathogen and its vector, the authors present the current data on bacterial and acarologic taxonomy. Then they describe their results to assess the mechanisms of circulation of the bacteria in the forests of Ile-de-France, particularly in the forest of Rambouillet. The combined study of abundance and infection frequency of the vectors, small mammals and cervids leads to the characterization of periods and areas of higher risk. The risk periods correlate with high density of I. ricinus nymphs. The risk areas correspond to those of high density of cervids. The role of reservoir of small mammals is confirmed, to the one of large mammals, so debated, is clearly demonstrated.

Environmental Health↗
PubMed1997

A case of relapsing psittacosis associated with a stroke.

Psittacosis, caused by Chlamydia psittaci, is mainly associated with an atypical pneumonia. We report a case of psittacosis where onset of respiratory symptoms was soon followed by the onset of focal neurological signs, a very uncommon feature. Despite adequate treatment with erythromycin, the patient relapsed when re-exposed to a sick pet bird. A prolonged course of doxycycline led to resolution of the pneumonia, but it is important to recall that successful management must also include the elimination of the precipitating cause of the infection.

Aged↗
PubMed1997

A study of autonomic cardiovascular reflexes in elderly patients with pneumonia.

People recovering from pneumonia are often weak for no apparent reason. Clinical features such as postural hypotension, arrhythmia and syndrome of inappropriate ADH have, in other circumstances, been attributed to impaired autonomic function. The aim of this study was to see whether elderly patients with pneumonia had impaired autonomic cardiovascular reflexes and, if so, how long this persisted. We compared healthy elderly controls, elderly controls with trauma (fractured femoral neck) and elderly patients with pneumonia. Thirty-eight subjects were studied in a series of cardiovascular autonomic function tests. Results suggest that elderly people have a high prevalence of impaired cardiovascular autonomic reflexes in the immediate post-pneumonic phase, and that this improves significantly after six weeks, with a further improvement by six months. Elderly patients recovering from pneumonia are predisposed to the adverse effects of drugs and other factors which can further impair autonomic cardiovascular reflexes.

Aged↗
PubMed1996

Annual influenza vaccination: immune response in patients over 10 years.

OBJECTIVE: To determine the effect of repeated annual influenza immunization on the host's serum antibody. DESIGN: Ten year observational study with cohort design. SETTING: Cystic Fibrosis Center at St. Vincent's Hospital and Medical Center, New York City, NY. PATIENTS: Thirty-eight children and young adults with cystic fibrosis (CF). MEASUREMENTS: Serum hemagglutination inhibition (HI) antibody titers were determined at the time of vaccination and 4 weeks later each year in the fall before the influenza epidemic. Shwachman scores were determined each year. RESULTS: While the pre-vaccination and post-vaccination geometric mean serum HI antibody titers varied from year to year, no upward or downward trend was evident over the 10 year period. The reciprocal of the post-vaccination geometric mean HI titers ranged annually from 32 to 74 for the influenza A (H3N2) vaccine strains, from 53 to 133 for the influenza A (H1N1) strains, and from 18 to 174 for influenza B strains. In addition, the majority of vaccinees had a presumably protective post-vaccination serum HI titer > or = 1:40 each year for all three vaccine strains. The initial mean Shwachman score of the group was 77. The final score of 76 after 10 years was not significantly different. CONCLUSIONS: Annual influenza vaccination appears to regularly induce presumably protective serum antibody levels in most CF children and young adults studied over a 10 year period.

Adolescent↗
PubMed1995

Factors associated with high risk of marginal hyperthermia in elderly patients living in an institution.

The elderly, the very young, and the sick are known to be adversely affected by high environmental temperatures. In a retrospective open case-note review of 872 patients in a large institution during a hot summer we identified characteristics in the elderly that increase the risk of marginal hyperthermia. Women were more likely to be affected than men (25.6% vs 16.9%). We found an age-related increase in marginal hyperthermia, 15.7% of those below 60 years developed a hyperthermia compared to 18.9% in those between 70-79 years (non-significant), 28.3% in those between 80-89 years (p = 0.01) and 50% in those above 90 years (p < 0.01). There was also a direct relationship between the incidence of hyperthermia and the ambient temperature (29% in the warmer wards, compared to 17.2% in cooler ones; p < 0.01) and with the level of dependence (42.3% of the bedridden group, p < 0.01, and 20.4% of the semi-dependent, p < 0.01, compared to 11.1% of the mobile group). These factors were more significant as predictors of risk than the diagnosis. Identifying high risk patients early and taking appropriate measures to avoid hyperthermia and dehydration is important to try to decrease mortality during heatwaves.

Adult↗
PubMed1995

An unusual cause of dementia.

Gliomatosis cerebri is a rare cerebral tumour that presents with personality and mental state changes. Diagnosis can be very difficult and many times is made at post mortem. We describe a 63-year-old man who presented initially with depression that merged into a schizophrenia-like illness, and who developed progressive dementia prior to his death. Two computed tomography (CT) scans of the brain were normal and the diagnosis of gliomatosis cerebri was made at post mortem. The progressively changing mental state was suggestive of an organic cause of his illness. Since this tumour may not be detected by a CT scan, a magnetic resonance imaging scan with T2-weighted images with spin echo sequences of the brain should be performed. Prognosis is very poor but diagnosis is important to plan terminal care. The patient described was unusual because he was older than most people with this tumour, and he presented with psychiatric symptoms which were thought to be non-organic for almost two years.

Brain Neoplasms↗
PubMed1994

Pituitary apoplexy after stimulation tests.

Pituitary apoplexy occurs after infarction of a non-neoplastic pituitary or sudden expansion of an adenoma following haemorrhage or infarction. It usually occurs spontaneously but can follow a number of causes including pituitary stimulation tests. Since this complication is potentially life-threatening, the benefits of subjecting patients who might have pituitary tumours to such tests should be considered.

Aged↗
PubMed1992

Transit through the proximal colon influences stool weight in the irritable bowel syndrome.

The inherent variability of symptoms and motor abnormalities in patients with the irritable bowel syndrome has hampered the demonstration of motor abnormalities that could underlie symptoms. The aim in the current study was to evaluate whether altered regional capacitance or transit of solid residue through the unprepared human gut were factors in the diarrhea of patients with the irritable bowel syndrome. In 10 such patients and in 5 healthy controls, gastric and small bowel transits were evaluated scintigraphically by means of a mixed meal containing 99mTc-labeled resin pellets. Regional colonic transit was quantitated by 111In-labeled pellets delivered to the ileocecal region by a pH-sensitive, methacrylate-coated capsule. Symptomatic patients did not have significantly altered gastric or small bowel transits, but colonic transit was accelerated in 7 of 10 persons with the irritable bowel syndrome (P less than 0.02), in the proximal colon of five patients and in the left colon of two patients. The 24-hour stool weight was positively correlated with the rate at which solid residue emptied from the ascending and transverse colons (r = 0.78; P less than 0.01). There was also an inverse relationship between emptying rates and maximal volumes accommodated by the proximal colon (r = -0.58; P less than 0.05), although the maximum volume of the proximal colon was not significantly different in patients and healthy subjects. Thus, accelerated transit through the proximal colon is a factor in the pathophysiology of the irritable bowel syndrome and influences the stool weight of such patients. The capacitance of the proximal colon presumably influences its storage capacity and, hence, the rate at which it empties.

Adult↗
PubMed1991

Scintigraphic measurement of regional gut transit in idiopathic constipation.

In this study, total gut transit and regional colonic transit in patients with idiopathic constipation were measured scintigraphically. Eight patients with severe constipation were studied, none of whom had evidence of abnormal function of the pelvic floor. 99mTc-radiolabeled Amberlite resin particles (average diameter, 1 mm; Sigma Chemical Co., St. Louis, MO) with a mixed meal were used to assess gastric emptying and small bowel transit; similar particles labeled with 111In were ingested in a coated capsule that dispersed in the ileocecal region. These were used to quantify colonic transit. Five healthy volunteers were also studied. Two patients showed delayed gastric emptying and two had slow small bowel transit. Seven of the eight patients had slow colonic transit. In five, delay affected the whole colon ("pancolonic inertia"); in two, transit in the ascending and transverse colon was normal, but solids moved through the left colon slowly. Mean colonic transit was also measured using radiopaque markers; this technique identified the patients with slow transit, as shown by measurements of overall colonic transit by simultaneous scintigraphy. However, estimated transit through the ascending and transverse colons was considerably shorter by the radiopaque marker technique. In conclusion, idiopathic constipation is characterized by either exaggerated reservoir functions of the ascending and transverse colons and/or impairment of propulsive function in the descending colon. Particle size may influence the result of regional colonic transit tests. Transit delays in other parts of the gut suggest that, in some patients, the condition may be a more generalized motor dysfunction.

Adult↗
PubMed1991

Gastrointestinal motor dysfunction in acquired selective cholinergic dysautonomia associated with infectious mononucleosis.

This report documents the disturbance in gastrointestinal motor function in a patient with selective cholinergic dysautonomia that occurred following acute infectious mononucleosis. Apart from the gut, other organs affected included the pupils, sweat glands, lacrimal and salivary glands, and urinary bladder. Autonomic function tests showed the preservation of sympathetic adrenergic functions in contrast to the generalized involvement of postganglionic parasympathetic and sympathetic cholinergic nerves, including denervation hypersensitivity of the pupil and urinary bladder to exogenous cholinergic agonists. Cardiac and abdominal vagal responses were abnormal. Colon myenteric plexus ganglion cells were normal by morphological and immunohistochemical studies, suggesting that the selective cholinergic dysautonomia was the most likely pathophysiologic process responsible for the observed motility disorder. This study documents the occurrence of selective cholinergic dysautonomia following a viral illness, the importance of the extrinsic neural control on the motor function of the gastrointestinal tract, and the usefulness of combined motility and autonomic function testing in the evaluation of patients with symptoms suggestive of gut dysmotility.

Adult↗
PubMed1991

Small intestinal motility and transit in disease.

Disorders of small intestinal motility and transit are becoming increasingly recognized partly as a result of a greater awareness of their existence and partly because suitable diagnostic methods are more widely available. Usually, the neuropathic and myopathic forms can be separated, and gut disease secondary to a generalized neuromuscular disorder can be identified by the clinician. The availability of better non-invasive methods for the diagnosis of disorders of motility and transit would greatly facilitate their management. Treatment must include the restoration and maintenance of nutrition, attempts to improve intestinal motor function and resection of any segments of localized disease. Regrettably, all such measures are ineffective in the severest cases. In the future, a greater understanding of the enteric neural control of the smooth muscle and an ability to manipulate it with novel, specific drugs or peptidergic receptor agonists and antagonists, or electrical pacing, may lead to more effective therapies.

Gastrointestinal Motility↗