Biomedical subjects

H C Pape

Publications and source records attributed to H C Pape.

At least 37 records · Page 2Linked to original sources

PubMed2001

Reinforcement of early long-term potentiation (early-LTP) in dentate gyrus by stimulation of the basolateral amygdala: heterosynaptic induction mechanisms of late-LTP.

The basolateral amygdala (BLA) can influence distinct learning and memory formation. Hippocampal long-term potentiation (LTP), the most prominent cellular model of memory formation, can be modulated by stimulation of the BLA in its induction and early maintenance. However, it is not known how the late maintenance of LTP beyond its initial phases might be affected. Behavioral stimuli have been shown to result in a reinforcement of a transient early-LTP into a lasting potentiation. Here we show that BLA stimulation mimics the behavioral effects on early-LTP in freely moving rats when the BLA is activated within a time window of 30 min before or after tetanization of the perforant path. The reinforcement of LTP was blocked by inhibitors of muscarinergic and beta-adrenergic but not dopaminergic receptors and was dependent on translation. Through these heterosynaptic associative interactions, hippocampal sensory information can be stabilized by amygdaloidal influences.

Adrenergic beta-Antagonists↗

PubMed2001

Control of glutamate and GABA release by nociceptin/orphanin FQ in the rat lateral amygdala.

The actions of the heptadecapeptide termed nociceptin or orphanin FQ (N/OFQ) and the recently discovered putative precursor product nocistatin were examined on synaptic transmission in putative projection cells of the rat lateral amygdala using the whole-cell patch-clamp technique. N/OFQ decreased evoked non-NMDA receptor-mediated excitatory postsynaptic current (EPSC) amplitudes in a concentration-dependent manner, with a half-maximal inhibitory effect elicited by 21.8 +/- 7.5 nM and a Hill coefficient of 0.8 +/- 0.2 (n = 22). Responses were maximally suppressed to 70.3 +/- 1.7 % of the control value. The effect of N/OFQ was prevented by 1 microM [Phe1[psi](CH2-NH)Gly2]NC(1-13)NH2 (Phe[psi]N/OFQ), a substance known as an antagonist/partial agonist of the ORL receptor. GABA(A) receptor-mediated inhibitory postsynaptic currents (IPSCs) elicited through intra-amygdaloid stimulation were reduced to 48.0 +/- 6.8 % by 1 microM N/OFQ (n = 5). Nocistatin had no measurable effect on evoked synaptic currents or membrane properties of recorded neurons. N/OFQ reduced the frequency of spontaneous miniature EPSCs and IPSCs to 74.0 +/- 2.6 % and 84.4 +/- 1.1 %, respectively, without affecting the amplitudes. The present findings indicate that N/OFQ, but not nocistatin, inhibits the release of glutamate and GABA in the lateral amygdala, presumably by acting on presynaptic release sites. These mechanisms may add to the role of N/OFQ in reducing stress vulnerability as recently proposed on the basis of behavioural and genetic approaches.

Amygdala↗

PubMed2001

Contribution of GABA(A) and GABA(B) receptors to thalamic neuronal activity during spontaneous absence seizures in rats.

The contribution of GABAergic mechanisms in thalamic relay nuclei to spike and wave discharges (SWDs) during spontaneous seizures was assessed using the WAG/Rij strain of rats, an established genetic model of absence epilepsy, in combination with single-unit recordings and microiontophoretic techniques in the ventrobasal thalamic complex in vivo. Spontaneous SWDs occurring on the electroencephalogram at 5-9 Hz were associated with burst firing in thalamocortical neurons, which was phase-locked with the spike component. Microiontophoretic application of the GABA(A) receptor antagonist bicuculline significantly increased the magnitude of SWD-related firing in all tested cells. Application of the GABA(B) receptor antagonist CGP 55845A exerted a statistically insignificant modulatory effect on neuronal activity during spontaneous SWDs but significantly attenuated the bicuculline-evoked aggravation of SWD-related firing. The data indicate that, in thalamocortical neurons, (1) GABA(A) receptor-mediated events are recruited with each SWD, (2) SWD-related activity can be evoked with no significant contribution of GABA(B) receptors, and (3) blockade of GABA(A) receptors potentiates SWD-related activity, presumably through an indirect effect mediated through GABA(B) receptors. These results vote against a predominant or even exclusive contribution of GABA(B) receptors to spontaneous SWDs in thalamic relay nuclei in the WAG/Rij strain, but rather point to a critical role of GABA(A) receptor activation. This conclusion is in support of the view that the two subtypes of GABA receptors play a differential role in fast (5-10 Hz) and slow (3 Hz) spike-wave paroxysms observed during absence seizures.

Action Potentials↗

PubMed2001

[Long-term outcome after multiple organ failure following severe trauma].

OBJECTIVE: The aim of this follow-up study was to find out if severely injured patients with multiple organ failure (MOF) show any organotopic sequelae in the late course. Additionally the occupational rehabilitation result as well as the reasons for a poor occupational result were investigated. METHODS: A total of 50 MOF patients with an injury severity of 45.3 +/- 2.1 PTS points were followed up 4.9 +/- 0.3 years after trauma. In order to show any organotopic sequelae, patients were examined and laboratory tests for the function of the lungs (function test, Horovitz-quotient), liver (bilirubin, GOT, bleeding time), and kidnies (creatinine, urea) were performed. The functional (locomotion and neurological system) and occupational rehabilitation results as well as the reasons for a poor occupational result were analysed. RESULTS: The clinical examination as well the functional and laboratory tests showed mainly normal results but in in 25% of the patients a significantly decreased range of motion of the elbow, hip, knee and ankle joint was found. The "return to work rate" was 64%. Reasons for a poor occupational result were the severity of head injury, a decreased range of motion of the hip joint and general physical fitness. CONCLUSIONS: Severely injured patients who survive MOF during their intensive care treatment, show no sequelae of organ failure. The occupational rehabilitation results were excellent with a "return to work rate" of 64% which was dependent on the severity of head injury, a decreased range of motion of the hip joint and general physical fitness.

Adolescent↗

PubMed2001

[Development of a standardized instrument for quantitative and reproducible rehabilitation data assessment after polytrauma (HASPOC)].

INTRODUCTION: Previous scoring systems for measurement of the quality of outcome are based on scores regarding injuries to individual body regions. Known scores which describe several organ regions are of no importance for trauma patients. Therefore a new rehabilitation outcome evaluation score was developed at our hospital. METHODS: Based on a prospective reinvestigation, a score system was developed that allows a quantitative appraisal of the subjective and objective outcome. A complete physical examination was performed, including ROM, neurologic examination and strength analysis. Part I (113 questions) is to be filled out by the patient; part II (191 questions) focusses on different body regions, physical examination and functional scoring. Included are the MFA, FIM, GCO and Frankel score. A final score (HASPOC) was developed to give a quantitative result of the outcome. RESULTS: The new score has a range from 5 to 411 points. One hundred and fifty patients were re-examined. The mean follow-up time was 2.2 +/- 0.1 years. The SF 12 indicated an outcome more than satisfactory in 63% of cases. The MFA demonstrated moderate or severe restrictions in 41%, in the case of injuries of the lower extremity in 52% of patients. The HASPOC indicated a mean of 44.5 points. CONCLUSION: This paper describes the development, structure, and the quantitative outcome of rehabilitation in polytrauma patients. This standardized rehabilitation instrument deals with a very heterogeneous patient population and shows the rehabilitation deficits accurately. Implemented recognized evaluations allow comparison of these results with those of other scoring systems.

Data Collection↗

PubMed2001

[Scoring multiple organ failure after severe trauma. Comparison of the Goris, Marshall and Moore scores].

INTRODUCTION: MOF scores are used to predict, describe and define organ failure. The aim of this study was to compare MOF scoring systems regarding their precision. METHODS: Data on the ICU course of 301 severely injured patients (PTS > 20, age > 16 years) were documented daily for calculation of three MOF Scores (Goris, Moore, Marshall) for 14 days. Every day the patients were graded by clinical criteria into a group with and a group without MOF by an experienced intensive care physician. The cut-off point for MOF was determined by ROC analysis for each score; the sensitivity and specificity were calculated. RESULTS: The patients were 36.3 +/- 1.0 years old, the mean injury severity was 36.2 +/- 0.7 points according to the PTS. Forty-seven (15.6%) of all patients died 17.7 +/- 5.6 days after trauma. The MOF incidence was 26.1%, the MOF mortality 58.4%. The calculated cut-off point for MOF was more than 4 points for the Goris and Marshall scores and more than 3 points for the Moore score. The Moore score is, with sensitivity of 81% and specificity of 88%, superior to the other scores. The Moore score identified 93 patients (30.9%) for MOF; this corresponds with a right answer in 85%. The lower specificity of the Goris and Marshall scores was due to the judgement of liver (GOT) and cardiovascular (PAH) dysfunction respectively. CONCLUSION: For evaluation of MOF after severe trauma the Moore score is superior to other scoring systems (sensitivity 81%; specificity 87%). A score of more than 3 points is associated with MOF. The Moore score did not consider distinct parameters (S-GOT, PAH) which are included in the other systems and were of little importance in our calculations.

Adult↗

PubMed2001

[Pronation and supination of the forearm. With special reference to the humero-ulnar articulation].

The development of a kinematic model of the pro- and supination, that can be used to predict the influence of angulations of ulna and radius on the pronation and supination is based on the precise knowledge of the pronation and supination movement. We performed two parallel studies for examining the pronation and supination motion of the human forearm. The first experiment dealt with MRI-studies on 18 probands (36 examined forearms). As a result we observed an evasive movement of the ulna during the rotation of 7, 14 degrees medial. In order to prove whether the evasive movement was caused by a rotation of the humerus or by an evasion in the articulatio humeroulnaris, we carried out a second experiment, using 30 preparations. The measurement of the pro- and supination motion with a fixed humerus was expedited using a special experimental setup which guaranteed that the ulna could move freely. In all cases we found the same magnitude of the evasive motion of the ulna. Therefore we demonstrated, that the ulna performs an evasive motion during the pro- and supination motion of the forearm that influences the kinematic behavior of the pro- and supination motion significantly.

Adult↗

PubMed2001

[Current situation of traffic accidents in children and adolescents. A medical and technical analysis].

HYPOTHESIS: Analysis of the current injury situation in road users not exceeding 14 years of age involved in road traffic accidents to allow conclusions regarding future prophylaxis. METHODS: Traffic accident reports and medical records from children (< 15 years of age) were analyzed for the following parameters: Type, location and mechanism of injury, Abbreviated Injury Scale (AIS), Maximum AIS (MAIS), Injury Severity Score (ISS), Delta-v, collision speed, type and duration of treatment. RESULTS: In 12,309 traffic accidents occurring in the area of Hannover, Germany between 1985 and 1998, 7.5% (n = 2,317) of the involved persons and 10.5% (n = 1,734) of the injured road users were children and adolescents. 70% sustained MAIS 1 injuries, 28% MAIS 2-4 and 1.5% MAIS 5/6 injuries. The mean ISS was 3.38. 30.3% of the injured children were car occupants, 32.1% bicyclists, 33.3% pedestrians. 30.3% of the children were unrestrained car occupants, 42.1% used safety belts designed for adults, 36% used special devices. Half of the children in cars remained uninjured, whereas only 8% of the bicyclists and 2% of the pedestrians were not injured. Severe injuries occurred in 20% of bicyclists and pedestrians at a collision speed less than 30 km/h and in 80% at more than 50 km/h. Half of those crashes could have been avoided, if the colliding vehicle would had driven about 15 km/h slower. CONCLUSION: Children have an especially high risk of injury if they are involved in accidents as pedestrians, bicyclists and unrestrained car occupants. Besides of improvements of the inner and outer car design, the use of adjusted restraining systems and bicycle helmets is likely to prevent from severe injuries. Speed reduction is a considerable factor. According to our data, the injury severity for bicyclists and pedestrians increases progressively when the collision speed exceeds 50 km/h.

Accidents, Traffic↗

PubMed2001

Contribution of intralaminar thalamic nuclei to spike-and-wave-discharges during spontaneous seizures in a genetic rat model of absence epilepsy.

In an epileptic rat model of generalized absence epilepsies, the genetic absence epilepsy rats from Strasbourg (GAERS), simultaneous recordings of bilateral epidural electroencephalogram (EEG) of the prefrontal cortex and unit activity of neurons in the intralaminar centrolateral (CL) and paracentral thalamic nucleus (PC) were performed under neurolept-anaesthesia (fentanyl-dehydrobenzperidol analgesia). Spike-and-wave (SW) seizures in these rats are characterized by generalized 7-10 Hz spike-and-wave discharges (SWDs) on the EEG. All neurons recorded in intralaminar thalamic nuclei during spontaneous SWDs showed high-frequency (average 368 Hz, range 200-500 Hz), burst-like activity, which occurred in a highly synchronized fashion with every SWD or with alternating SWD-complexes. Burst discharges in intralaminar neurons were delayed by 13.1 ms (CL) and 12.7 ms (PC), with respect to the spike component of a given SWD on the EEG, whereas burst discharges in the ventrobasal thalamus (VB) and in the rostral nucleus reticularis thalami (rRT) preceded the spike component by 17.8 ms and 8.3 ms, respectively. The onset of SWDs on the EEG was preceded by a tonic firing pattern (20-50 Hz) in about one third of CL and PC neurons. Microiontophoretic application of the gamma-aminobutyric acid (GABA)A receptor antagonist bicuculline aggravated, whereas, the glutamate receptor antagonists DNQX and APV dampened, SWD-related discharges in PC and CL; the GABAB receptor antagonist CGP 35347 had no measurable effect. These data indicate that intrathalamic nuclei are recruited rhythmically during SWDs, through mechanisms that seem to rely on a delayed glutamatergic excitation modulated by GABAergic influences, rather than a GABA-mediated rebound burst activity typical of relay cells. The finding of a temporal delay of SWD-related activity in intrathalamic, compared with "specific" thalamic relay nuclei, does not support the notion of a leading or pacemaker role in SWD generation. It is, however, rather suggestive of a function of intrathalamic neurons during synchronization and maintenance of neuronal oscillations, and these intrathalamic neurons may be recruited through glutamatergic corticofugal inputs.

Action Potentials↗

PubMed2001

[Definition of shock types].

Definitions of shock types. Hypovolaemic shock is a state of insufficient perfusion of vital organs with consecutive imbalance of oxygen supply and demand due to an intravascular volume deficiency with critically impaired cardiac preload. Subtypes are haemorrhagic shock, hypovolaemic shock in the narrow sense, traumatic-haemorrhagic shock and traumatic-hypovolaemic shock. Cardiac shock is caused by a primary critical cardiac pump failure with consecutive inadequate oxygen supply of the organism. Anaphylactic shock is an acute failure of blood volume distribution (distributive shock) and caused by IgE-dependent, type-I-allergic, classical hypersensibility, or a physically, chemically, or osmotically induced IgE-independent anaphylactoid hypersensibility. The septic shock is a sepsis-induced distribution failure of the circulating blood volume in the sense of a distributive shock. The neurogenic shock is a distributive shock induced by generalized and extensive vasodilatation with consecutive hypovolaemia due to an imbalance of sympathetic and parasympathetic regulation of vascular smooth muscles.

Anaphylaxis↗

PubMed2001

Cellular processes in the amygdala: gates to emotional memory?

The amygdala is considered a core structure of the so-called limbic system and has been implicated in a variety of functions, including emotional interpretation of sensory information, emotional arousal, emotional memory, fear and anxiety, and related clinical disorders. Despite the clinical and functional importance of the amygdala, it is only recently that some general principles of intra-amygdaloid mechanisms of signal processing that are relevant for fear behavior and memory have emerged from behavioral, anatomical, electrophysiological, and neurochemical studies performed in the amygdala of various mammalian species in vivo, in situ and in vitro.

Journal Article↗

PubMed2001

Dehydroepiandrosterone decreases mortality rate and improves cellular immune function during polymicrobial sepsis.

OBJECTIVE: Sepsis is associated with a marked depression of cellular immune function. The steroid hormone dehydroepiandrosterone (DHEA) is proposed to have immunoenhancing activities. We, therefore, investigated the effect of DHEA on the mortality rate and cellular immune functions in an experimental model of sepsis. DESIGN: Randomized animal study. SETTING: Level I trauma center, university research laboratory. SUBJECTS: Male NMRI mice. INTERVENTIONS: Mice were subjected to laparotomy (sham) or cecal ligation and puncture (CLP). Mice were treated with (sham/DHEA; CLP/DHEA) or without (sham; CLP) the steroid hormone DHEA (30 mg/kg sc). Animals were killed 48 hrs after the onset of sepsis. MEASUREMENTS AND MAIN RESULTS: The survival rate of septic mice was determined 24 and 48 hrs after onset of sepsis. Forty-eight hours after the septic challenge, a white blood cell count was performed and serum tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta concentrations were monitored using ELISA. Furthermore, the delayed type of hypersensitivity (DTH) reaction was evaluated on the basis of ear pinna swelling after dinitrofluorobenzene (DNFB) administration, and clinical variables (body weight, temperature, heart rate, fluid input/output, food intake) were monitored using metabolic cages. DHEA administration improved the survival rate (87% vs. 53% after 48 hrs; p <.001). This was accompanied by a restoration of the depressed DTH reaction and a reduction in TNF-alpha serum concentrations (20.7 +/- 1.4 pg/mL vs. 32.4 +/- 6.6 pg/mL). CONCLUSIONS: These results demonstrate that DHEA administration leads to an increased survival following a septic challenge. The immunoenhancing effect of DHEA is accompanied by a reduction of TNF-alpha release and an improved activity of T-cellular immunity. DHEA administration may, therefore, be beneficial in systemic inflammation.

Adjuvants, Immunologic↗

PubMed2001

Heterotopic ossifications in patients after severe blunt trauma with and without head trauma: incidence and patterns of distribution.

OBJECTIVE: To investigate the incidence and distribution of heterotopic ossifications in patients with blunt multiple trauma with and without associated head trauma. DESIGN: Retrospective. SETTING: Level I trauma center. PATIENTS: Patients were included if they were treated between August 1987 and September 1995. Inclusion criteria included age between 16 and 65 years, injury severity score (ISS) of more than twenty points, and clinical reexamination performed more than three years after the initial injury. METHODS: The records of each patient were abstracted to determine the ISS, the Glasgow coma score (GCS), and parameters describing the course of intensive care. For each patient, a reexamination was performed between January and September 1998. Patients with multiple trauma and associated head trauma (Group PTH, polytrauma, GCS less than nine points, and head computed tomography scan abnormalities) and patients with multiple trauma without associated head trauma (Group PT, polytrauma, GCS of at least nine points, and normal head computed tomography scans) were compared. A clinical reexamination was performed to evaluate functional outcome. RESULTS: Sixty-four patients belonged to Group PTH and 124 patients belonged to Group PT. There were no differences in the age (Group PTH, 28.9 +/- 1.6 years; Group PT, 29.2 +/- 2.1 years) or severity of injury (ISS Group PTH, 31.0 +/- 5.3 points; ISS Group PT, 33.0 +/- 6.1 points) among patients in the two groups. The overall incidence of periarticular heterotopic ossification was comparable in patients with multiple trauma with and without head injury (Group PTH, 30 of 64 patients [46.9 percent]; Group PT, 53 of 124 patients [42.7 percent]). The duration of ventilation was significantly higher in Group PT (Group PTH, 9.3 +/- 2.4 days; Group PT, 14.2 +/- 3.1 days; p = 0.02). In the subgroups in which heterotopic ossification developed (PT-HO and PTH-HO), patients in PT-HO had a significantly higher incidence of heterotopic ossification, as compared with patients in PTH-HO at initially uninjured joints (Group PTH-HO, 1 of 30 patients [3.3 percent]; Group PT-HO, 10 of 53 patients [18.9 percent]; p = 0.04). CONCLUSIONS: There was a high incidence of heterotopic ossification around those joints that were initially classified as uninjured in patients without head trauma. This finding suggests that pathogenic pathways independent of head trauma, such as long-term ventilation, play a main role. Causative factors for the development of heterotopic ossification at initially uninjured joints in long-term ventilated patients with multiple trauma with and without head trauma remain to be elucidated.

Adult↗

PubMed2001

Major secondary surgery in blunt trauma patients and perioperative cytokine liberation: determination of the clinical relevance of biochemical markers.

BACKGROUND: The aim of this study is to assess the associations between the timing of secondary definitive fracture surgery on inflammatory changes and outcome in the patient with multiple injuries. The study population consists of a series of patients with multiple injuries who were managed using a strategy of primary temporary skeletal stabilization followed by delayed definitive fracture fixation. METHODS: In a prospective cohort study performed at a Level I trauma center, the patients' injuries and operative details as well as immune markers and clinical outcomes were studied. The patients were split into an early secondary surgery group (group ESS, surgery at days 2-4) and a late secondary surgery group (group LSS, surgery at days 5-8). During the posttraumatic course, inflammatory markers (interleukin [IL]-6, tumor necrosis factor-alpha) were determined on a daily basis. Perioperatively, these markers were additionally evaluated at 30 minutes, 7 hours, and 24 hours after initiation of surgery. RESULTS: Secondary surgery on days 2 to 4 was associated with a higher incidence of postoperative organ dysfunction (n = 33 [46.5%]) than secondary surgery on days 5 to 8 (n = 9 [15.7%], p = 0.01). A significant association between the combination of initial IL-6 values > 500 pg/dL plus surgery on days 2 to 4 and the development of multiple organ failure (r = 0.96, p < 0.001) occurred. A correlation between the initial IL-6 values > 500 pg/dL and surgery on days 5 to 8 (r = 0.57, p < 0.07) could not be found. IL-6 also demonstrated a predictive value for the development of multiple organ failure: IL-6 > 500 pg/dL in group ESS, r = 0.96, p < 0.001; IL-6 > 500 pg/dL in group LSS, r = 0.57, p < 0.07. CONCLUSION: According to our data, no distinct clinical advantage in carrying out secondary definitive fracture fixation early could be determined. In contrast, in patients who demonstrated initial IL-6 values above 500 pg/dL, it may be advantageous to delay the interval between primary temporary fracture stabilization and secondary definitive fracture fixation for more than 4 days. In patients with blunt multiple injuries undergoing primary temporary fixation of major fractures, the timing of secondary definitive surgery should be carefully selected, because it may act as a second hit phenomenon and cause a deterioration of the clinical status.

Adolescent↗

PubMed2001

Correlation between crash severity, injury severity, and clinical course in car occupants with thoracic trauma: a technical and medical study.

BACKGROUND: The crash mechanisms and clinical course of car occupants with thoracic injury were analyzed to determine prognostic factors and to create a basis for injury prophylaxis. METHODS: A technical and medical investigation of car occupants with a thoracic injury (Abbreviated Injury Scale-thorax [AIS(THORAX)] > or = 1) at the scene of the crash and the primary admitting hospital was performed. RESULTS: Between 1985 and 1998, 581 car occupants sustained a thoracic injury. Mean parameter values were as follows: AIS(THORAX), 2.5; Hannover Polytrauma Score (PTS), 21.4; Injury Severity Score (ISS), 24.2; Delta-v, 49.6 km/h (30.8 mph); and extent of passenger compartment deformation (DEF) (scale, 1--9), 4.0. In 19% (n = 112) of patients involved, the clinical course was evaluated: AIS(THORAX), 2.5; PTS, 20.0; ISS, 19.3; Delta-v, 50.1 km/h (31.1 mph); DEF, 3.9; intensive care unit time, 8.3 days; ventilation time, 5.7 days; and hospital stay, 15.3 days. In the groups with higher AIS(THORAX), ISS, PTS, and intensive care unit and ventilation time, higher Delta-v and DEF occurred. In patients with longer hospital stay, higher Delta-v, but no difference in DEF occurred. CONCLUSION: The injury severity and the clinical course demonstrated a positive correlation with the crash severity. Therefore, our technical accident analysis allows prediction of the severity of injury and the clinical course. It may consequently serve as a tool for development of more sophisticated injury prevention strategies and may improve passive car safety.

Abbreviated Injury Scale↗

PubMed2001

Glycine reduces the inflammatory response and organ damage in a two-hit sepsis model in rats.

The goal of this study was to investigate whether prefeeding of glycine reduces the immunoinflammatory response, the degree of distant organ injury (liver), and/or the mortality rate in a two-hit model using intestinal ischemia/reperfusion and endotoxin (ET) challenge 6 h later in rats. The liver damage was greatest at 24 h after ET challenge and completely inhibited by glycine. The early systemic increase of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL) -6 as well as the secretion of the antiinflammatory cytokine IL-10 was reduced by glycine. Tissue cytokine mRNA expression (TNF-alpha, IL-1beta, IL-10) was decreased in the lung and the liver but not in the mesenteric lymph node or ileum, in the glycine-fed group. However, glycine did not decrease the mortality rate. These results suggest that prefeeding of glycine reduces liver damage as well as the systemic and local (lung and liver) inflammatory response after intestinal ischemia/reperfusion and endotoxin challenge in rats.

Amino Acids↗

PubMed2001

Modulation by extracellular pH of low- and high-voltage-activated calcium currents of rat thalamic relay neurons.

The effects of changes in the extracellular pH (pH(o)) on low-voltage- (LVA) and high-voltage- (HVA) activated calcium currents of acutely isolated relay neurons of the ventrobasal thalamic complex (VB) were examined using the whole cell patch-clamp technique. Modest extracellular alkalinization (pH 7.3 to 7.7) reversibly enlarged LVA calcium currents by 18.6 +/- 3.2% (mean +/- SE, n = 6), whereas extracellular acidification (pH 7.3 to 6.9) decreased the current by 24.8 +/- 3.1% (n = 9). Normalized current amplitudes (I/I(7.3)) fitted as a function of pH(o) revealed an apparent pK(a) of 6.9. Both, half-maximal activation voltage and steady-state inactivation were significantly shifted to more negative voltages by 2-4 mV on extracellular alkalinization and to more positive voltages by 2-3 mV on extracellular acidification, respectively. Recovery from inactivation of LVA calcium currents was not significantly affected by changes in pH(o). In contrast, HVA calcium currents were less sensitive to changes in pH(o). Although extracellular alkalinization increased maximal HVA current by 6.0 +/- 2.0% (n = 7) and extracellular acidification decreased it by 11.9 +/- 0.02% (n = 11), both activation and steady-state inactivation were only marginally affected by the moderate changes in pH(o) used in the present study. The results show that calcium currents of thalamic relay neurons exhibit different pH(o) sensitivity. Therefore activity-related extracellular pH transients might selectively modulate certain aspects of the electrogenic behavior of thalamic relay neurons.

Acids↗

PubMed2001

Primary subtalar arthrodesis of calcaneal fractures.

We evaluated retrospectively the long-term results of isolated calcaneal fractures treated with open reduction and internal fixation and a primary subtalar arthrodesis. From 1990 to 1997 258 patients were treated with a calcaneal fracture, for the current study six patients were included. Six different surgeons operated on the patients. The indication for the fusion was based on the comminution of the posterior facet according to the preoperative CT as well as the intraoperative evaluation of destruction of the cartilage. The restoration of length, axes and angles of the calcaneus was almost anatomical in all cases. Follow-up was done at a mean of 4.9 (2.5 - 7.5 years). Using the AOFAS score, the results were good or excellent in five patients. In one patient with a painful arthritis in the talonavicular joint and hyperesthesia of the sural nerve, the results were fair. All returned to their profession within 9 months and had no or only minor daily restrictions. The results are comparable with single surgeon series. We found open reconstruction of the calcaneus with primary fusion of the subtalar joint may be indicated in selected patients and, in these 6 patients led to good results.

Arthrodesis↗