Chronic intermittent hypoxia elicits serotonin-dependent plasticity in the central neural control of breathing.

We tested the hypothesis that chronic intermittent hypoxia (CIH) elicits plasticity in the central neural control of breathing via serotonin-dependent effects on the integration of carotid chemoafferent inputs. Adult rats were exposed to 1 week of nocturnal CIH (11-12% O(2)/air at 5 min intervals; 12 hr/night). CIH and untreated rats were then anesthetized, paralyzed, vagotomized, and artificially ventilated.

[Intracranial hemorrhages in infants: child abuse or a congenital coagulation disorder?].

In children with head injuries the severity of the neurological symptoms should concord with the patient's history and signs of neurotrauma on examination. Discrepancies between the (hetero)anamnesis and physical examination on the one hand and neurological findings on the other may indicate child abuse. The presence of both old and new intracranial haemorrhages in the absence of proportional trauma is generally considered as evidence for child abuse.

Effects of academic stress on oral hygiene--a potential link between stress and plaque-associated disease?

Background: While there seems to be a common belief that psychosocial stress affects oral hygiene behavior, this assumption has rarely been proved. The present study thus aims to analyse stress effects on oral hygiene.

Material And Methods: 16 matched pairs of medical students each consisting of 1 student participating in a major academic exam and 1 control without current academic stress, were formed on the basis of baseline plaque levels.

Effects of phrenicotomy and exercise on hypoxia-induced changes in phrenic motor output.

To investigate models of plasticity in respiratory motor output, we determined the effects of chronic unilateral phrenicotomy and/or exercise on time-dependent responses to episodic hypoxia in the contralateral phrenic nerve. Anesthetized (urethane), ventilated, and vagotomized rats were presented with three, 5-min episodes of isocapnic hypoxia (11% O(2)), separated by 5 min of hyperoxia (50% O(2)). Integrated phrenic (and hypoglossal) nerve discharge were recorded before and during each hypoxic episode, for the first 5 min after the first hypoxic episode, and at 30 and 60 min after the final episode.

The human transcriptional repressor protein NAB1: expression and biological activity.

The zinc finger protein early growth response 1 (Egr-1) is a transcriptional activator involved in the regulation of growth and differentiation. Egr-1 has a large activating domain and three zinc finger motifs that function as a DNA binding region. We show here that a third functional domain of the Egr-1 protein, localized between the extended activation domain and the zinc finger DNA binding region, acts as a transcriptional repressor domain when fused to a heterologous DNA binding domain (DBD).

Increased spinal monoamine concentrations after chronic thoracic dorsal rhizotomy in goats.

In goats, bilateral thoracic dorsal rhizotomy (TDR) causes severe ventilatory failure during exercise, followed by progressive functional recovery. We investigated spinal neurochemical changes associated with TDR and/or functional recovery by measuring spinal concentrations of the monoamines serotonin (5-HT), norepinephrine, and dopamine via HPLC. Changes in 5-HT and calcitonin gene-related peptide were visualized with immunohistochemistry.

Long term facilitation of phrenic motor output.

Episodic hypoxia or electrical stimulation of carotid chemoafferent neurons elicits a sustained, serotonin-dependent augmentation of respiratory motor output known as long term facilitation (LTF). The primary objectives of this paper are to provide an updated review of the literature pertaining to LTF, to investigate the influence of selected variables on LTF via meta-analysis of a large data set from LTF experiments on anesthetized rats, and to propose an updated mechanism of LTF. LTF has been demonstrated in anesthetized and awake experimental preparations, and can be evoked in some human subjects during sleep.

Molecular fingerprinting of Mycobacterium tuberculosis strains isolated in Vietnam using IS6110 as probe.

Setting: Northern and Southern areas of Vietnam.

Objective: To study the correlation between DNA fingerprinting of 168 Mycobacterium tuberculosis strains isolated from patients with a particular historical past (political separation of Vietnam for 20 years) and data about geographical origin, drug susceptibility, HIV infection and BCG vaccination status.

Methods: Comparison of restriction fragment length polymorphism (RFLP) patterns produced by Southern hybridization of Pvull-digested chromosomal DNA.

Effects of activated macrophages and fibroblast growth factor on random skin flap survival in swine.

Objective: To examine the effect of application of activated autologous macrophages and basic fibroblast growth factor (FGF) on random skin flap survival in swine.

Design: A randomized nonblinded controlled trial. According to a standard design, six dorsally based, random-pattern skin flaps were raised in each of 12 Yorkshire pigs.

Post-hypoxia frequency decline in rats: sensitivity to repeated hypoxia and alpha2-adrenoreceptor antagonism.

We tested the hypothesis that the post-hypoxia frequency decline of phrenic nerve activity following brief, isocapnic hypoxic episodes in rats is diminished by prior hypoxic episodes and alpha2-adrenoreceptor antagonism. Anesthetized (urethane), artificially ventilated (FIO2=0.50) and vagotomized rats were presented with two or three, 5 min episodes of isocapnic hypoxia (FIO2 approximately 0.

Acute coalescent mastoiditis in an infant: an emerging trend?

There is some evidence to suggest that the incidence and complications of ACM may be increasing. However, in the current era of widespread access to health care and broad-spectrum antibiotics, an intratemporal or intracranial complication from acute otitis media may not initially be suspected. The reported case is significant in that the patient was very young, had no underlying disease or immunocompromise, and did not have a known antecedent acute otitis media.

Cervical dorsal rhizotomy enhances serotonergic innervation of phrenic motoneurons and serotonin-dependent long-term facilitation of respiratory motor output in rats.

We tested the hypothesis that spinal plasticity elicited by chronic bilateral cervical dorsal rhizotomy (C3-C5; CDR) has functional implications for respiratory motor control. Surgery was performed on rats (CDR or sham-operated) 26 d before phrenic motoneurons were retrogradely labeled with cholera toxin. Rats were killed 2 d later, and their spinal cords were harvested and processed to reveal the cholera toxin-labeled phrenic motoneurons and serotonin-immunoreactive terminals.

Hypercapnia-induced long-term depression of respiratory activity requires alpha2-adrenergic receptors.

We investigated the effects of repeated hypercapnic episodes (inspired CO2 fraction = 0.10) on posthypercapnic respiratory nerve discharge. Anesthetized (urethan), vagotomized, and artificially ventilated rats were presented with three consecutive 5-min episodes of hyperoxic hypercapnia, separated by 5 min of hyperoxic normocapnia (inspired O2 fraction = 0.

Modulation of ventilatory control during exercise.

The control of ventilatory responses to mild or moderate dynamic exercise has been the subject of considerable debate for over a century. The prevailing view has been that the ventilatory response to exercise is stereotypical and rather unmalleable. However, paradigms involving novel associations of stimulus inputs have been shown to modulate breathing in short and longer time scales.

Hypoxia-induced long-term facilitation of respiratory activity is serotonin dependent.

Repeated isocapnic hypoxia evokes long-term facilitation (LTF) of phrenic nerve activity in rats. We wished to determine: (1) whether hypoxia-induced LTF is serotonin dependent; and (2) whether hypoxia-induced LTF is a property of upper airway motoneurons. Phrenic and hypoglossal nerve activities were recorded in urethane anesthetized, vagotomized, paralyzed and artificially ventilated rats (n = 7).

Phrenic responses to contralateral spinal stimulation in rats: effects of old age or chronic spinal hemisection.

Serotonin reveals ineffective spinal pathways from the C2-lateral funiculus to contralateral phrenic motoneurons in young adult rats with acute spinal hemisection. We tested the hypothesis that old age (1.5-2 years) or chronic hemisection (3-5 days) strengthens these pre-existing crossed spinal pathways.

[Prevention of postoperative pulmonary complications after heart-lung surgery. Comparison of 3 different mask physiotherapy regimens].

The object of the investigation was to compare the effect of three different physiotherapy masks on the incidence of postoperative complications after thoracic surgery. It was carried out as a prospective, consecutive, randomized comparison at a Department of Thoracic and Heart Surgery at a University Hospital. The therapy was performed by experienced and specially trained physiotherapists.

Serotonin reveals ineffective spinal pathways to contralateral phrenic motoneurons in spinally hemisected rats.

Serotonin reveals ineffective (subthreshold) pathways from the C2 lateral funiculus to ipsilateral phrenic motoneurons in spinalized rats. The objective of the present study was to investigate serotonergic modulation of crossed-spinal pathways to contralateral phrenic motoneurons. Rats (n = 10) were anesthetized (urethane), paralyzed, vagotomized, and artificially ventilated.

Time-dependent phrenic nerve responses to carotid afferent activation: intact vs. decerebellate rats.

The objectives were to determine 1) respiratory responses to carotid chemoreceptor inputs in anesthetized rats and 2) whether the cerebellar vermis plays a role in these responses. A carotid sinus nerve was stimulated (20 Hz) with five 2-min trains, each separated by approximately 3 min. During stimulation, respiratory frequency (f), peak amplitude of integrated phrenic nerve activity (integral of Phr), and their product (f x integral of Phr) immediately increased.

Serotonin is necessary for short-term modulation of the exercise ventilatory response.

The exercise ventilatory response is augmented during conditions of increased respiratory dead space (delta Vd), a phenomenon that we refer to as short term modulation (STM). To test the hypothesis that serotonin is necessary in the mechanism underlying STM, experiments were conducted on ten awake goats. Ventilation, CO2 production and PaCO2 were measured at rest and during treadmill exercise (4 km/h, 5% grade), with and without delta Vd (0.

Three different mask physiotherapy regimens for prevention of post-operative pulmonary complications after heart and pulmonary surgery.

Objective: An investigation into the incidence of post-operative complications after thoracic surgery with 3 different physiotherapy masks.

Design: A prospective, consecutive, randomized comparison.

Setting: Department of Thoracic and Heart Surgery at a University Hospital.

Phantom-related phenomena after rectal amputation: prevalence and clinical characteristics.

Phantom sensations are well known and almost inevitable sequels to limb amputation, whereas similar phenomena are only rarely described after rectum amputation (phantom rectum). Our study attempted to assess the frequency and character of phantom rectum. All surviving patients (n = 22), who had undergone abdominoperineal surgical resection of the rectum in the period 1980-1986 at our clinic, were interviewed by a standard questionnaire and underwent a physical examination.

[Concentration of selenium in nutrition and blood serum of diabetic children and adolescents].

During 6 days the food of 7 patients of an instruction center for juvenile diabetics contained 60.94 +/- 2.87 micrograms selenium/day.