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Restoration of plantar sweat secretion in the feet of leprosy patients.

As part of the studies on nerve damage and its consequences in leprosy, the status of sweat gland function in the anaesthetic sole of the feet of leprosy patients was investigated qualitatively and semi-quantitatively, before and after surgical decompression of the posterior tibial neurovascular bundle. Sweat prints of the feet of the patients were obtained pre-operatively and postoperatively on Whatman's No. 1 filter paper. The paper was treated with one percent Ninhydrin and the intensities of the Ninhydrin positive areas were quantitated. Forty one feet of thirty six patients have been studied in this manner. Sweat print analysis of twenty normal people have also been done, and included for comparison. This operative procedure has been found to effect an improvement in the sweat gland function in the feet of more than fifty percent of leprosy patients studied so far.

Foot↗

[The use of noninvasive study objects in the clinic].

Results are submitted of the gas-chromatographic analysis of sweat lipids higher fatty acids (FA) spectrum in patients with different skin diseases. Polyunsaturated FA were found to be on the decrease at the expense of linoleic FA. Arachidonic FA tended to be on the increase. The gas-chromatographic analysis will, we believe, help in assessing disturbed bodily lipid metabolism.

Adult↗

Electron probe X-ray microanalysis of cellular ions in the eccrine secretory coil cells during methacholine stimulation.

Intracellular concentrations of Na, K, Cl ([Na], [K] and [Cl], respectively) and other elements were determined in isolated monkey eccrine sweat secretory coil cells using quantitative electron probe X-ray microanalysis of freeze dried cryosections. The validity of the methodology was partially supported by qualitative agreement of the X-ray microanalysis data with those obtained by micro-titration with a helium glow spectrophotometer. [Na], [K] and [Cl] of the cytoplasm were the same as those in the nucleus in both clear and dark cells. [Na], [K], and [Cl] of the clear cells were also the same as those of the dark cells at rest and after stimulation with methacholine (MCh), suggesting that these two cell types behave like a functional syncytium. MCh stimulation induced a pharmacologically specific, dose-dependent decrease in [K] and [Cl] (as much as 65%), and a 3.7-fold increase in [Na]. In myoepithelial cells, a similar change in [Na] and [K] was noted after MCh stimulation although the decrease in [Cl] was only 20%. The MCh-induced change in [Na], [K] and [Cl] was almost completely inhibited by removal of Ca2+ from the medium. 10(-4) M bumetanide inhibited the MCh-induced increase in [Na], reduced the decrease in [K] by about 50%, but slightly augmented the MCh-induced decrease in [Cl]. 10(-4) M ouabain increased [Na] and decreased [K] as did MCh; however, unlike MCh, ouabain increased [Cl] by 56% after 30 min of incubation. Thus the data may be best interpreted to indicate that Ca-dependent K efflux and (perhaps also Ca-dependent) Cl efflux are the predominant initial ionic movement in muscarinic cholinergic stimulation of the eccrine sweat secretory coils and that the ouabain-sensitive Na pump plays an important role in maintenance of intracellular ions and sweat secretion.

Animals↗

Clinical pharmacokinetics of amfetamine and related substances: monitoring in conventional and non-conventional matrices.

Consumption of amfetamine-type stimulants, including classical amfetamines and 'designer drugs', has been recognised as one of the most significant trends in drug abuse at the end of the past century and at the beginning of the current one. The first cause is the increasing consumption amongst youth of methylenedioxy- and methoxy-substituted amfetamines, of which the pharmacology in humans is currently under investigation. Secondly, the abuse of more classical amfetamines, such as amfetamine itself and metamfetamine, continues to be highly prevalent in some geographical regions. Amfetamines are powerful psychostimulants, producing increased alertness, wakefulness, insomnia, energy and self-confidence in association with decreased fatigue and appetite as well as enhanced mood, well-being and euphoria. From a clinical pharmacokinetic perspective, amfetamine-type stimulants are rather homogeneous. Their oral bioavailability is good, with a high distribution volume (4 L/kg) and low binding to plasma proteins (less than 20%). The elimination half-life is 6-12 hours. Both hepatic and renal clearance contribute to their elimination from the body. Hepatic metabolism is extensive in most cases, but a significant percentage of the drug always remains unaltered. Amfetamine and related compounds are weak bases, with a pKa around 9.9, and a relatively low molecular weight. These characteristics allow amfetamine-type stimulants to diffuse easily across cell membranes and lipid layers and to those tissues or biological substrates with a more acidic pH than blood, facilitating their detection in alternative matrices at relatively high concentrations. In most cases, the concentrations found are higher than expected from the Henderson-Hasselbach equation. Drug monitoring in non-conventional biological matrices (e.g. saliva, hair, nails, sweat) has recently gained much attention because of its possible applications in clinical and forensic toxicology. An individual's past history of medication, compliance or drug abuse can be obtained from testing of hair and nails, whereas data on current status of drug use can be provided by analysis of sweat and saliva. Because of the physicochemical properties of amfetamine-type stimulants, this group of drugs is one of the most suitable for drug testing in non-conventional matrices.

Amphetamine↗

Borderline sweat test: criteria for cystic fibrosis diagnosis.

The CF diagnosis can be difficult in subjects with disease consistent symptoms and borderline values of the sweat test. This study aimed to evaluate possibly resolutory criteria. Seventy-one ill subjects with borderline sweat test values (40-70 mEq/l Cl-) aged 0.1-37.7 years (mean, 8.7; SD, 7.3) were studied and compared with 33 age-matched CF patients (Cl- over 75 mEq/l) and 25 healthy subjects. A complex CF score based on 25 variables was set: CF-specific clinical conditions, detailed analysis of sweat test (salt-free diet test included), pancreatic function, Pseudomonas infection, and others. The score ranged from 0 to a maximum of 65 and clearly distinguished the CF patients from the healthy subjects. Therefore the CF score was assumed as the best reference criterion to define the diagnosis in the borderline group: 27 of them (38%) were assigned to the CF condition and 44 (62%) to the healthy one, with a quite clear separation between the 2 subgroups. With respect to these assignments, the most discriminant variable turned out to be the sweat Cl- persisting above 40 mEq/l after 5 days of salt-free diet (mean error, 18.4%). Neither sweat Cl-/Na+ ratio nor bicarbonate duodenal output showed better discriminant power (mean error, 29% and 25%, respectively). It is concluded that in borderline situations of sweat test results a definite CF diagnosis can be achieved only by compounding many clinical and laboratory data with a preference for the sweat test after a salt-free diet period. The CF score proposal can be an effective help.

Adult↗

Studies of trans-3-methyl-2-hexenoic acid in normal and schizophrenic humans.

The report that sweat of certain schizophrenics contains the branched chain fatty acid, trans-3-methyl-2-hexenoic acid (TMHA), stimulated an investigation to evaluate the relationship between this fatty acid and schizophrenia. A sensitive and specific gas-liquid chromatography-mass spectroscopic procedure was developed for analyzing biological fluids for TMHA. Analysis of sweat samples from normal and schizophrenic subjects indicated that the sweat of both groups contains comparable quantities of this fatty acid. In addition, the fate of intravenously administered (14)C-labeled TMHA was shown to be similar in normal and schizophrenic subjects. It is concluded that there is no relationship between TMHA and schizophrenia.

Caproates↗

Detection of dermcidin-derived peptides in sweat by ProteinChip technology.

Recently, a novel antimicrobial peptide DCD-1, derived from the Dermcidin (DCD) gene and secreted by sweat glands, has been described by Schittek et al. [Nat. Immunol. 2 (2001) 1133.]. Here we describe the application of the surface-enhanced laser desorption/ionisation (SELDI) technology for the detection of DCD-1 and other dermcidin-derived peptides directly from microlitre amounts of human sweat. The advantages of the technique are as follows: (a) it can be carried out with ease and rapidity; (b) multiple samples can be processed simultaneously; (c) prior purification is not required; and (d) only a limited sample volume is necessary for both protein profiling and semiquantitation. Profiling of human sweat from various donors revealed that in addition to DCD-1, other DCD-derived peptide species were also present in significant quantities. Four of five identified peptides were DCD-1 related, while the fifth corresponded to a portion of the DCD protein outside the DCD-1 core. This provides clues as to how the novel protein is processed to its active form, though further work remains to elucidate this fully. Thus, we have demonstrated the applicability of such technology to the detection of DCD-1 and for the protein profiling of sweat in general. Such studies could reveal valuable new biomarkers for diagnosis and treatment of skin and sweat gland disorders.

Amino Acid Sequence↗

The use of oral fluid and sweat wipes for the detection of drugs of abuse in drivers.

Blood, urine, oral fluid (by spitting or with a Salivette), and sweat samples (by wiping the forehead with a fleece moistened with isopropanol) were obtained from 180 drivers who failed the field sobriety tests at police roadblocks. With quantitative GC-MS, the positive predictive value of oral fluid was 98, 92, and 90% for amphetamines, cocaine, and cannabis respectively. The prevalence of opiate positives was low. The proposed SAMHSA cut-off values for oral fluid testing at the workplace, proved their usefulness in this study. The positive predictive value of sweat wipe analysis with GC-MS was over 90% for cocaine and amphetamines and 80% for cannabis. The accuracy of Drugwipe was assessed by comparing the electronic read-out values obtained on-site after wiping the tongue and the forehead, with the corresponding GC-MS results in plasma, oral fluid, and sweat. The accuracy was always less than 90% except for the amphetamine-group in sweat.

Amphetamine↗

Inconsistencies in sweat testing in UK laboratories.

BACKGROUND: Sweat testing procedures are perceived to vary widely. AIM: To evaluate variability in sweat collection, analysis, and interpretation. METHODS: Questionnaire responses from 30 self selected centres: 15 paediatric centres, and 15 district general hospitals. RESULTS: Centres carried out 30-400 tests per year (median 100), with a diagnostic rate of 1:5-152 (median 1:30). Staff performed 5-268 tests per year. Minimum test age varied from 24 hours to four months. All stimulated sweating by pilocarpine iontophoresis using varying currents and times. Twenty six had observed urticaria or skin reddening, and nine blistering or burns. Sweat was collected for 10-60 minutes onto filter paper or into Macroduct coils. Between 2% and 25% of tests were considered insufficient. Twenty eight measured sodium, 24 chloride, and one osmolality and conductivity. Fifteen used literature and five in house reference ranges. Eleven would not test severely eczematous children. CONCLUSIONS: Local audit is required to improve performance, as well as a national guideline to standardise collection, and external quality assessment to provide analytical feedback.

Age Factors↗

Effects of changing hypothalamic temperature on eccrine sweating in the patas monkey.

Two male (10-13 kg) patas monkeys (Erythrocebus patas) were implanted with bilateral thermodes to control hypothalamic temperature. Animals were restrained in primate chairs and instrumented to yield hypothalamic (THYPO), colonic (Tc), and mean skin (Tsk) temperatures, chest sweat rate (mSW), and heart rate (HR). THYPO was monitored using a thermocouple inserted to the tip of a non-perfused thermode; mSW was measured using resistance hygrometry. After the monkey equilibrated to a selected ambient temperature, four thermodes were perfused with water from a temperature-controlled bath. Increasing THYPO from 37 to 41 degrees C increased mSW from 0.05 to 0.30 mg.cm-2.min-1. Reducing Tsk shifted the THYPO:mSW relationship to the right (p less than 0.05) without significantly altering its slope. Activity-induced changes in HR, when THYPO was constant, caused fluctuations in ongoing sweating that closely tracked HR. We conclude that mSW in the patas monkey is controlled by both peripheral and central thermal inputs and nonthermal factors.

Animals↗

Allometry of primate hair density and the evolution of human hairlessness.

Allometric analyses of hair densities in 23 anthropoid primate taxa reveal that increasingly massive primates have systematically fewer hairs per equal unit of body surface. Considering the absence of effective sweating in monkeys and apes, the negative allometry of relative hair density may represent an architectural adaptation to thermal constraints imposed by the decreasing ratios of surface area to volume in progressively massive primates. Judging by estimates of body volume, denudation of the earliest hominids should have progressed to a considerable extent prior to their shift from a forest to a grassland habitat during the Pliocene. We propose that, lacking a reflective coat of hair, the exploitation of eccrine sweating emerged as the primary mechanism for adaptation to the increased heat leads of man's new environment and permitted further reduction of the remnant coat to its present vestigial condition.

Animals↗

Autonomic dysfunction in the Landry-Guillain-Barre syndrome.

Tests of autonomic function have been performed on 7 patients with the Landry-Guillain-Barre syndrome and 5 control subjects. These included a sweat test, and measurement of both postural hypotension and baroreflex sensitivity. Sweating was definitely abnormal in 5 patients. Postural hypotension was present in 4 patients. The baroreflex sensitivity was significantly reduced (p less than 0.01) in the patients when compared with the control group. The results demonstrate that both the sympathetic and parasympathetic nervous systems may be affected in the Landry-Guillain-Barre syndrome.

Adult↗

Time evolution of the number of functional murine eccrine sweat glands after irradiation: a quantitative analysis of experimental data using a model of proliferative and functional organization.

The function of eccrine sweat glands in the beta-pad of the mouse foot after irradiation was followed over time. Graded doses of X-rays were given to the foot, either as single doses or in two equal fractions separated by a 24-h interval. A quantitative, non-invasive, functional assay was used allowing repeated evaluation of the animals. Sweat gland function was assessed once a week for the first 6 weeks, and at 8, 10, 14, 18, 28, 38 and 45 weeks after irradiation. The beta-pad of the unirradiated foot was used as a control. The function dropped to a nadir within 8-10 weeks after irradiation, whereafter it gradually recovered, reaching a stable level 20-25 weeks after irradiation. These data were analyzed using a mathematical model of proliferative and functional organization of the sweat pore. The model provides a description of the time evolution of pore function, and its basic features were as follows. The functional subunit is a single sweat pore, which will be assayed as functional provided that it contains a number of functional cells above a critical threshold. The functional cells are capable of self renewal (a so-called 'flexible' tissue), and the proportion of proliferating cells is subject to homeostatic control. Irradiation is assumed to transfer a certain fraction of the cells into a state with a limited probability of successful division. This fraction is assumed to have a linear-quadratic dependence on dose. The values of all free model parameters were optimized by a maximum-likelihood fit to the experimental data. With optimized parameter values, the initial decrease, nadir, and long-term level of tissue function estimated from the model were in close agreement with the experimental observations for all the 28 dose groups. Some of the estimated model parameters are: growth fraction 4.2 +/- 0.2%; cell cycle time, 0.95 +/- 0.04 days; number of functional cells in a single pore in the unirradiated animal, 9.9 +/- 0.5; and alpha/beta ratio, 4.3 Gy (95% confidence interval 3.1-5.0 Gy). It is concluded that the present model, despite its relative mathematical simplicity, provides a close description of the postirradiation kinetics of functional cells in the mouse sweat gland.

Animals↗

A simple clinical staging system that predicts progression to AIDS using CD4 count, oral thrush, and night sweats.

OBJECTIVE: To develop a simple clinical staging system based on CD4 count and clinical variables that predicts progression to AIDS in HIV-infected non-AIDS patients. DESIGN: Retrospective cohort study. SETTING: A primary care outpatient clinic for HIV-infected patients at a VA Medical Center. PATIENTS: One hundred seventy-six HIV-infected non-AIDS patients seen at the Houston VA Special Medicine Clinic between January 1986 and December 1990 and followed for a mean of 22 months. Fifty-four patients (31%) progressed to AIDS during follow-up. MEASUREMENTS: The medical records were reviewed, and data corresponding to the initial (baseline) clinic visit and subsequent six-month visits were extracted. MAIN RESULTS: "Predictive" baseline variables (i.e., those associated with progression to AIDS) were first identified and then examined in Cox proportional hazards modeling. In the final model, CD4 category, oral thrush, and night sweats made significant independent contributions. A three-stage prognostic system was constructed by assigning points to the three variables: CD4 > 500 cells/mm3 = 0; 500 > or = CD4 > or = 200 = 1; CD4 < 200 = 2; presence of oral thrush = 1; presence of night sweats = 1. Stages were assigned as follows: stage I = 0 points, stage II = 1-2 points, and stage III = 3-4 points. The proportions of patients who progressed to AIDS were: stage I, 6/39 (15%); stage II, 31/106 (29%); and stage III, 17/31 (55%). CONCLUSIONS: These results demonstrate that simple, clinically sensible prognostic staging systems that predict progression to AIDS can be constructed using CD4 count and clinical variables.

AIDS-Related Opportunistic Infections↗

Serum interleukin 6 levels are elevated in lymphoma patients and correlate with survival in advanced Hodgkin's disease and with B symptoms.

Several cytokines including gamma-interferon, tumor necrosis factor alpha, interleukin 1 beta (IL-1 beta), and interleukin 6 (IL-6) are pyrogenic and can inhibit lipogenic processes. Because patients with lymphoma often suffer from fever, weight loss, and night sweats (B symptoms), the etiology of which is unknown, the authors investigated serum levels of these cytokines in normal volunteers and in patients with Hodgkin's and non-Hodgkin's lymphoma. Sixty serum samples from patients with Hodgkin's disease (28 patients) or non-Hodgkin's lymphoma (32 patients), as well as 20 samples from normal volunteers, were collected. The majority of patients had advanced (Stage III or IV) or relapsed disease. The assay for gamma-interferon was a specific and sensitive radioimmunoassay (lower limit of detection = 0.1 unit/ml); the assays for tumor necrosis factor alpha, IL-1 beta, and IL-6 were enzyme-linked immunoassays with lower limits of sensitivity of 10 pg/ml, 20 pg/ml, and 22 pg/ml, respectively. There were no statistically significant differences in gamma-interferon, tumor necrosis factor alpha, or IL-1 beta levels between lymphoma patients and normal subjects. In contrast, 20 of 57 patients (35%) with lymphoma as compared with 0 of 19 normal volunteers (0%) had detectable serum IL-6 levels (P < 0.005, chi 2 test). Interestingly, 17 of 29 lymphoma patients with B symptoms (59%) as opposed to 3 of 28 lymphoma patients without B symptoms (11%) had detectable serum IL-6 levels (P < 0.001, chi 2 test); the median IL-6 level was 28.9 pg/ml (B symptoms present) versus undetectable (no B symptoms) (P < 0.005, Mann-Whitney U test). Analyzing Hodgkin's and non-Hodgkin's lymphoma groups separately revealed similar results. IL-6 levels showed no significant correlation with time from diagnosis, beta 2-microglobulin, or lactate dehydrogenase levels. However, analysis by the method of Kaplan and Meir demonstrated that the median survival of Hodgkin's disease patients with detectable IL-6 levels (> or = 22 pg/ml) was 10 mo, whereas the median survival has not been reached at a median follow-up time of 37.5 mo in those patients with lower values (Wilcoxon P value = 0.0012). There were too few patients in each subset of non-Hodgkin's lymphoma to determine the correlation between IL-6 and survival but, considered as a single group, a statistically significant correlation was not found.(ABSTRACT TRUNCATED AT 400 WORDS)

Actuarial Analysis↗

A retrospective study of 44 canine apocrine sweat gland adenocarcinomas.

Apocrine sweat gland adenocarcinomas (AACs) are relatively uncommon skin tumors in dogs. Little prognostic or behavioral information has been published for these tumors. In this retrospective study, 44 AACs from diagnostic archives were reexamined and clinical postexcisional follow-ups for 25 of the 44 cases were obtained by a survey. There were 28 out of 44 (65.9%) AACs that invaded the capsule, stroma, or both, 5 of 44 (11.4%) invaded blood vessels and stroma, and 1 out of 25 (4%) had distant metastases. The presence or absence of stromal and vascular invasion was predicted by clinical examination with more than 80% accuracy. Postexcisional median survival of dogs with AACs was 30 mo at the time of survey. Determination of a correlation between histological features and malignant behavior of AACs was compromised by the low number of cases with clinical AAC-related problems; however, it appears that intravascular invasion is an important indicator of potential systemic metastases.

Adenocarcinoma↗