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S Smitz

Publications and source records attributed to S Smitz.

At least 19 recordsLinked to original sources
PubMed2003

Regional variability in mottled subclinical melanoderma in the elderly.

The density in melanin chromatophores becomes heterogeneous in the epidermis during the early events of photoaging. Little is known about the regional variability in the resulting mottled skin appearance on the sun-exposed parts of the body in the elderly. The relationship between these features and the dermal atrophy related to aging is also an area ripe for study. The aim of the present study was to objectively assess and compare such aspects of photoaging in older subjects. A computer-assisted video camera equipped with an internal ultraviolet-emitting unit (Visioscan) was used in combination with image analysis to quantify the infraclinical mottling of the skin on the forehead, neck and dorsal forearm. A Densi Score device served to assess the dermal atrophy by rating the skin folding capacity. A mottled subclinical melanoderma was disclosed on the three evaluation sites in all subjects irrespective of their phototypes. Three main patterns were identified corresponding to regular perifollicular dots, streaky macules along shallow wrinkles and unevenly shaped macules in the interfollicular area. The extent in melanoderma was larger on the forehead than on the neck and forearm. The age after 60 years did not influence the severity of mottled melanoderma, but clearly altered the skin folding capacity. The greatest inter-individual differences in mottled melanoderma were found in phototype II subjects. In conclusion, infraclinical mottled melanoderma is present in all individuals after 60 years of age. This type of epidermal photoaging does not appear to be influenced in older ages. By contrast, skin laxity due to dermal aging continues to progress beyond the age of 60 years.

Aged↗
PubMed2000

Comparison of rectal and infrared ear temperatures in older hospital inpatients.

OBJECTIVES: To assess the agreement between infrared emission detection (IRED) ear and rectal temperatures and to determine the validity of IRED ear thermometry in detecting rectal fever. DESIGN: Prospective, convenience sample, unblinded study. SETTING: An acute geriatric unit (teaching hospital) and a multidisciplinary intensive care unit. PARTICIPANTS: The study included 45 inpatients (26 women and 19 men), aged 78.3+/-6.9 years, admitted over a 4-month period. Twelve of the patients were definitely infected. MEASUREMENTS: Sequential rectal (RT) and ear temperature (ET) measurements were performed using mercury-in-glass and IRED ear thermometers, respectively. IRED ear temperatures were measured at both ears (unadjusted mode), with the highest of six ear temperatures considered the true value. RESULTS: Mean RT (37.39 degrees C +/- 0.52 degrees C) was significantly (P<.001) higher than mean ET (36.89 degrees C +/-0.59 degrees C). A highly significant positive correlation was found between RT and ET (slope = 0.69; 95% CI, 0.52-0.86; P<.001; r = 0.78). The mean bias (mean of the differences) between RT and ET was 0.50 degrees C +/-0.37 degrees C (95% CI, 0.41 degrees C-0.59 degrees C), and the 95% limits of agreement -0.22 degrees C and 1.23 degrees C (95% CI, -0.38 degrees C to 1.39 degrees C). According to the standard criterion (RT > or =37.6 degrees C), 14 patients were febrile. Using an optimum IRED ear fever threshold (37.2 degrees C), the sensitivity and specificity of IRED ear thermometry for predicting rectal fever were 86% and 89%, respectively (positive predictive value, 80%; negative predictive value, 93%). CONCLUSIONS: The degree of agreement between rectal temperature and the highest of six IRED ear temperatures was acceptable. Using an optimal IRED ear fever threshold of 37.2 degrees C (99 degrees F), IRED ear thermometry had acceptable sensitivity and specificity for predicting rectal fever.

Aged↗
PubMed1998

[Vascular surgery in octogenarians].

The prevalence of peripheral vascular disease increases with aging of the population. About 8% of the octogenarians present significant carotid artery stenosis, about 4% have an abdominal aortic anneurysm of 40 mm or more, and 6% suffer critical limb ischemia. Carotid endarterectomy in octogenarians is a valuable tool for stroke prevention, only if the combined perioperative stroke-mortality rate is lower than 3%. Operating an abdominal aneurysm of 50 mm or more in octogenarians is characterized by an operative mortality that is higher compared to that observed in a younger patient group (4.7% vs 2.7%). Aneurysm-surgery remains nevertheless justified, since it is the only way to prevent the evolution to rupture, that is almost fatal. Limb salvage surgery should always be considered for an 80-years patient with critical limb ischemia, since readaptation after major limb-amputation is not evident for octogenarians. An extensive review of literature is presented concerning vascular aging and results of carotid surgery, aneurysm repair and lower limb revascularization in octogenarians. The authors report their own recent experience with carotid surgery and aneurysm repair in patients aged 80 years or older.

Aged↗
PubMed1997

[Hyponatremia].

Explore the source record for details and available documents.

Acute Disease↗
PubMed1996

Evidence for circulating vasopressin-like peptides in a case of polyuria.

Plasma immunoreactive vasopressin (iAVP) was studied by RIA in a patient suffering from polyuria during chronic treatment with lithium. The combined use of two antisera specific for different regions of the AVP molecule allowed us to detect circulating forms which are modified in the acyclic tripeptide portion. In this lithium-treated patient, iAVP was abnormally low with respect to plasma osmolality. However, iAVP increased during hypertonic saline infusion, probably through an osmosensitive mechanism. A remarkable finding was that contrary to the observations made in healthy subjects and in another patient with diabetes insipidus, iAVP measured with the antiserum specific for the acyclic portion of the AVP molecule was below the values measured with the antiserum specific for the hexapeptide ring. This unusual immunoreactivity profile suggests that the plasma of this polyuric lithium-treated patient contains vasopressin-like peptides which differ from arginine vasopressin in the structure of the C-terminal tripeptide tail.

Female↗
PubMed1993

[Is age a limiting factor for carotid surgery?].

To evaluate the role of carotid surgery in elderly patients 75 years and older, we reviewed 912 carotid endarterectomies performed on 806 patients between 1987 and 1990. There were 151 patients (19% of the whole series) aged 75 years and older (160 endarterectomies, group A), including 29 octogenarians, vs 655 patients under 75 years of age (group B). There were more women in the elderly age group (44%) than in the younger one (38%). Symptoms, risk factors, operative outcome and follow up data of the two groups were compared. The risk profile was similar for the two age groups, with exception for coronary heart disease, less frequent in the older patient group (25% had previous infarction vs 44%). Indication for carotid endarterectomy was different in the two age groups: 41% of group A underwent prophylactic thrombendarterectomy for high degree stenosis, while only 30% of group B had asymptomatic carotid disease. In group A, 6% of the patients had carotid endarterectomy after recovering from a mild stroke, vs 2% in group B. Angiography revealed bilateral carotid disease in 59% of the group A patients (including 15% with contralateral occlusion) vs 40% in group B. Operative mortality was 1.5% for the younger age group vs 2.5% for the older age group. The cause of death was cardiac in 60%. A follow up is available for all patients who benefited carotid endarterectomy since 1976, including 180 patients aged 75 years or older.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1988

Identification of vasopressin-like peptides in the plasma of a patient with the syndrome of inappropriate secretion of antidiuretic hormone and an oat cell carcinoma.

In this study we have identified and characterized several vasopressin-like peptides in the plasma of a patient with the syndrome of inappropriate antidiuretic hormone secretion and oat cell carcinoma of the lung. Immunoreactive plasma vasopressin was measured after gel filtration (Sephadex G-25) or C-18 cartridge extraction using two different region-specific antisera: AS1 and AS2. Antiserum AS1 is more specifically directed towards the antigenic site of the hexapeptidic ring of arginine-vasopressin (AVP), whereas AS2 is more specifically directed towards the C-terminal region of AVP. Unexpectedly, the Sephadex G-25 gel filtration elution profile of the immunoreactive vasopressin was very heterogeneous, indicating the presence of several molecular species. After extraction of total AVP and AVP-like peptides of this plasma, an unusual AS1/AS2 ratio of immunoreactivity was observed, suggesting the presence of vasopressin-like peptides which differ from AVP in the C-terminus.

Aged↗
PubMed1985

Adipsic hypernatremia in a patient with pseudotumor cerebri and the primary empty sella syndrome.

Adipsic hypernatremia, a rare disorder, usually secondary to a hypothalamic lesion, is caused by the combination of partial central diabetes insipidus with hypo- or adipsia. We studied a patient who presented with a global hypothalamic dysfunction including adipsic hypernatremia. An extensive work-up disclosed the presence of pseudotumor cerebri and an empty sella turcica. Although endocrine abnormalities including true diabetes insipidus have been reported in conjunction with pseudotumor cerebri or an empty sella, no patient described presented such a global hypothalamic dysfunction or adipsic hypernatremia. The increased intracranial pressure is postulated to be the responsible mechanism for both the empty sella and the hypothalamic dysfunction.

Adult↗
PubMed1985

Syndrome of inappropriate secretion of antidiuretic hormone after severe head injury.

This study is based on 109 patients with severe head injury who had a Glasgow coma score equal to or less than 7 and a Liège coma score equal to or less than 12 in the first 24 hours. The syndrome of inappropriate secretion of antidiuretic hormone seems to us to be a frequent complication of severe craniocerebral trauma. It has been discovered in 33% of our patients. On the other hand, diabetes insipidus was rarely diagnosed (2.8%). We propose, in cranial trauma, to subdivide the syndrome of inappropriate secretion of antidiuretic hormone into two clinical forms: an early syndrome (5%) that becomes apparent towards the second day and is significantly associated with lesions at the base of the skull; and a delayed syndrome that occurs at the end of the first week and is related to different factors inherent in intensive care procedures. Surgical intervention, in the case of acute craniocerebral trauma, does not result in a higher frequency of inappropriate secretion of antidiuretic hormone.

Adolescent↗
PubMed1985

Release of human neurophysin I during insulin-induced hypoglycemia in depressed patients is abolished after recovery with clomipramine treatment.

Release of human neurophysin I (hNp I) and neurophysin II (hNp II) during insulin-induced hypoglycemia was studied in 10 unipolar depressed women before and after 4-5 weeks of standard antidepressant drug treatment with daily intravenous infusions of clomipramine. Before treatment, a significant increase of hNp I but not of hNp II serum levels in response to hypoglycemia was observed. At retest during clomipramine administration, a marked clinical amelioration occurred in all patients as determined with the Hamilton Rating Scale for Depression; the hNp I response to insulin was abolished, but no effect on hNp II concentration could be demonstrated. No correlation was found between the degree of the depression score decrease and the amplitude of the inhibition of hNp I release or serum levels of clomipramine or its metabolite, desmethylclomipramine. The meaning of this difference in reactivity of the neurohypophyseal system in the course of depressive illness, based on the pharmacological and biochemical profiles of clomipramine action, is discussed.

Blood Glucose↗
PubMed1985

High molecular weight vasopressin: detection of a large amount in the plasma of a patient.

Using a sensitive and specific radioimmunoassay for arginine-vasopressin, we have searched for the presence of high molecular weight (HMW) vasopressin in the plasma of a patient with the syndrome of inappropriate antidiuretic hormone secretion (SIADH) and an oat cell carcinoma of the lung. After incubation in 8 mol/l urea, one millilitre of the plasma from this patient was fractionated on a Sephadex G-50 column and the immunoreactive vasopressin content was evaluated before and after trypsin treatment of the eluted fractions. A wide peak of apparent mol. wt. 2500-6000 daltons was revealed only after tryptic digestion of each fraction. This peak contained the equivalent of 1900 pg of vasopressin. A tryptic digest of this peak, rechromatographed on Sephadex G-25, gave two small peptides the major one eluting at a position identical to vasopressin. These results demonstrate the presence of a large amount of HMW vasopressin in the plasma of a patient with SIADH and oat cell carcinoma of the lung.

Aged↗
PubMed1985

Regulation of vasopressin secretion in a patient with chronic hypernatraemia.

A patient with the chronic hypernatraemia syndrome is described. Using a sensitive and specific radioimmunoassay, the plasma arginine-vasopressin (AVP) level was measured under various conditions. With an unrestricted diet, the plasma AVP level was inappropriately low for the degree of plasma hyperosmolality (0.9 pmol/l and 302 mOsm/kg, respectively). After chronic water loading, plasma osmolality was 271 mOsm/kg, plasma AVP level 1.5 pmol/l, and the urine remained hypertonic with respect to the plasma. During hypertonic saline infusion, plasma osmolality increased from 271 to 294 mOsm/kg without a concomitant increase in the plasma AVP concentration. After sc injection of apomorphine and after haemodynamic stimulation, the plasma AVP concentration increased from 0.8 to 36 pmol/l and from 1.2 to 6.3 pmol/l, respectively. These data demonstrate a selective deficiency in the osmoregulation of the AVP secretion. The observed neuroendocrine abnormalities may be linked to a congenital malformation of the brain.

Adult↗