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M R Gomez

Publications and source records attributed to M R Gomez.

At least 37 records · Page 2Linked to original sources
PubMed1992

Practical aspects of achieving positive energy balance in low birth weight infants.

For the low birth weight (LBW) infant, energy balance during the first several days of life usually is equated to absorption of sufficient energy to match energy expenditure. Most studies show that energy expenditure of nongrowing LBW infants is 45 to 55 kcal/kg/day. Hence, for energy equilibrium, energy intake minus energy losses (i.e., metabolizable energy intake) must be at least 50 kcal/kg/day. Intakes above this amount result in energy storage or positive energy balance, whereas lesser intakes necessitate mobilization of endogenous energy stores (negative energy balance). Some of the problems of achieving positive energy balance in LBW infants (e.g., feeding intolerance and fear of necrotizing enterocolitis) can be circumvented by use of parenterally delivered nutrients. On balance, virtually all LBW infants will tolerate parenteral amino acid, glucose, and lipid intakes, respectively, of 2, 5, and 1 gm/kg/day or an energy intake of about 40 kcal/kg/day. It usually is possible to increase energy intake of most infants by an additional 10 kcal/kg/day. Whether this is achieved with enterally delivered nutrients or additional parenteral glucose or lipid intake, including the necessary modifications to enhance tolerance (e.g., insulin, 20% vs 10% lipid emulsions, and lipid emulsions containing medium-chain fatty acids), must be decided for each infant based on his or her underlying condition, likelihood of tolerating either substrate, and the impact of intolerance on the underlying condition. The consequences of not providing an essential nutrient during the immediate postnatal period also must be considered. The fact that essential fatty acid deficiency develops more rapidly in infants receiving isocaloric (60 kcal/kg/day) parenteral intakes with versus without amino acids, the likelihood that brain growth continues despite negative energy balance, and the possibility that LBW infants may not be able to desaturate/elongate linoleic and linolenic acids to the more unsaturated, longer-chain fatty acids that are deposited in the developing brain suggest that these infants may require exogenous intakes of specific fatty acids.

Energy Intake↗
PubMed1992

CT and MR imaging of intracranial tuberous sclerosis.

CT and MR have permitted radiology to play a greater, but not definitive, role in detecting the pathologic components of tuberous sclerosis. SEN may be identified in only 80% of patients. Tubers are more ubiquitous and readily identified by MR in children and adults when the brain is myelinated. Since tubers are predominantly peripheral hypomyelinated lesions, the detection of small lesions may be delayed until an infant is over 16-18 months of age when the myelin will have extended to the junction between the cortical white and gray matter. SEGA typically evolve later during the first and second decades of life. Successful genetic counseling implies a need to detect tuberous sclerosis at a stage during infancy when imaging may fail to confirm the diagnosis, so tuberous sclerosis remains a clinical diagnosis.

Adolescent↗
PubMed1991

Tuberous sclerosis complex in Olmsted County, Minnesota, 1950-1989.

The incidence of tuberous sclerosis complex in Olmsted County, Minnesota, was 0.28 per 100,000 person-years from 1950 through 1989, the point prevalence on December 31, 1989, was 6.9 per 100,000 persons, and the incidence at birth was 6.0 per 100,000 live births. The incidence was 0.13 per 100,000 person-years from 1950 through 1974 and 0.46 per 100,000 person-years from 1975 through 1989. The higher rate of diagnosis during the later period is believed to be due to the use of computed tomography. Of the 12 patients considered in this study, one patient presented with seizures and severe intellectual disability, six patients presented with seizures, three patients presented with multiple facial angiofibroma, and two patients were asymptomatic.

Female↗
PubMed1991

Environmental-occupational risk factors and familial associations in multiple system atrophy: a preliminary investigation.

We studied 60 patients with multiple system atrophy and autonomic failure and 60 control subjects matched for age, sex and race. Their psychosocial history, pedigree and occupation were obtained by personal interview. An inventory of autonomic and neurologic symptoms was obtained from 148 first-degree relatives of the patients and 80 controls by a self-administered questionnaire. Patients with multiple system atrophy had significantly more potential exposures to metal dusts and fumes, plastic monomers and additives, organic solvents, and pesticides than the control population. The potential exposures were determined in most subjects by their reported usual occupation. Clinical symptoms of multiple system atrophy were reported by a significantly larger group of patients' relatives than controls. These findings are possibly consistent with the hypothesis that multiple system atrophy develops as a result of a genetically determined selective vulnerability in the nervous system. Specific neuronal systems may become targets for environmental insults or toxins, and the disease state may occur when ageing neuronal systems can no longer sustain functional capacity. This preliminary study supports the need to further explore possible environmental, occupational, and familial contributions to the aetiology of multiple system atrophy.

Environment↗
PubMed1991

Causes of death in patients with tuberous sclerosis.

Of the 355 patients with tuberous sclerosis complex (TSC) examined at the Mayo Clinic, 49 had died (9 of causes other than TSC). We attempted to determine what pattern of organ involvement occurred most often in the 40 patients who died of TSC. One baby died of cardiac failure due to cardiac rhabdomyomas, and one child died of rupture of an aneurysm of the thoracic aorta. Eleven patients died of renal disease, which was the commonest cause of death. Ten patients died as a result of brain tumors, and four patients (who were 40 years of age or older) died of lymphangiomyomatosis of the lung. Thirteen patients with severe mental handicaps died of either status epilepticus or bronchopneumonia; in all but one of these patients, the only source of information was the death certificate. Survival curves show a decreased survival for patients with TSC in comparison with that for the general population. Patients with TSC need lifelong follow-up for early detection of potentially life-threatening complications.

Adolescent↗
PubMed1991

Is colloid cyst of the third ventricle a manifestation of nevoid basal cell carcinoma syndrome?

A 14-year-old girl with nevoid basal cell carcinoma syndrome presented with intermittent headache and nausea. Magnetic resonance imaging and a computed tomographic scan of the head revealed a colloid cyst of the third ventricle and mild dilatation of the lateral ventricle. The cyst was successfully removed by stereotaxic surgery. The occurrence of two rare disorders in the same patient could be a coincidence. Other similar patients must be found before it is established that the colloid cyst is part of the nevoid basal cell carcinoma syndrome.

Adolescent↗
PubMed1991

[Subependymal giant cell astrocytoma].

Subependymal giant-cell astrocytomas (SEGA) are rare brain tumors. They occur typically in the walls of the lateral ventricles and very seldom in the wall of the third ventricle. In our experience, all patients with SEGA have had tuberous sclerosis. Between January 1950 and May 1990, of our 345 patients with tuberous sclerosis 22 were found to have SEGA. The diagnosis being made histologically in symptomatic cases or by clinical or neuroradiologic methods. The histological, immunohistochemical and ultrastructural features of this unique tumor are discussed. To date, histopathologic methods have not resolved the issue of whether these tumors are exclusively astrocytic or neuronal in nature, or show features of both. Modern immunohistochemical and/or molecular-biological techniques will no doubt elucidate the histogenesis of this highly characteristic, albeit polymorphous tumor.

Adult↗
PubMed1991

Subependymal giant cell astrocytoma: a clinical, pathological, and flow cytometric study.

Of 345 patients with tuberous sclerosis complex evaluated at the Mayo Clinic from 1950 to 1989, 23 were identified as having brain tumors. In 20 of the 23, histological or clinical evidence showed the tumor to be a subependymal giant cell astrocytoma. A search of the Mayo Clinic tissue registry yielded 73 giant cell-containing astrocytomas and intraventricular gliomas exclusive of ependymomas. Reexamination revealed no further examples of subependymal giant cell astrocytoma in patients without features of the tuberous sclerosis complex. Considerable histological variation was observed in the 15 subependymal giant cell astrocytomas subjected to critical microscopic review. It is of note that no correlation was noted between either the histological features, such as atypia, mitoses, endothelial proliferations, necrosis, or the flow cytometric characteristics and the clinical course or the survival time of the patients.

Adolescent↗
PubMed1990

Muscle disease in children: a practical approach.

This paper has given an overview of the complexity of childhood muscle disease. Fortunately, astute history-taking and physical examination, combined with readily available tests, will usually enable the clinician to formulate a diagnosis and plan of management.

Child↗