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PubMed2004

In-hospital care pathways for stroke.

BACKGROUND: Stroke care pathways have the potential to promote organised and efficient patient care that is based on best evidence and guidelines, but evidence to support their use is unclear. OBJECTIVES: We aimed to assess the effects of care pathways, compared with standard medical care, among patients with acute stroke who had been admitted to hospital. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (last searched in June 2003), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2003), MEDLINE (1975 to June 2003), EMBASE (1980 to June 2003), CINAHL (1982 to June 2003), ISI Proceedings: Science & Technology (1990 to November 2003), and HealthSTAR (1994 to May 2001). We also handsearched the Journal of Integrated Care Pathways (2001 to 2003), formerly Journal of Managed Care (1997 to 1998) and Journal of Integrated Care (1998 to 2001). Reference lists of articles were searched. SELECTION CRITERIA: We considered randomised controlled trials and non-randomised studies that compared care pathway care with standard medical care. DATA COLLECTION AND ANALYSIS: One reviewer selected studies for inclusion and the other independently checked the decisions. Two reviewers independently assessed the methodological quality of the studies. One reviewer extracted the data and the other checked the extracted data. MAIN RESULTS: Three randomised controlled trials (340 patients) and 12 non-randomised studies (4081 patients) were included. There was significant statistical heterogeneity in the analysis of many of the outcomes. We found no significant difference between care pathway and control groups in terms of death or discharge destination. Patients managed with a care pathway were: (a) more dependent at discharge (P = 0.04); (b) less likely to suffer a urinary tract infection (Odds Ratio (OR) 0.51, 95% Confidence Interval (CI) 0.34 to 0.79); (c) less likely to be readmitted (OR 0.11, 95% CI 0.03 to 0.39); and (d) more likely to have neuroimaging (OR 2.42, 95% CI 1.12 to 5.25). Evidence from randomised trials suggested that patient satisfaction and quality of life were significantly lower in the care pathway group (P = 0.02 and P < 0.005 respectively). REVIEWERS' CONCLUSIONS: Use of stroke care pathways may be associated with positive and negative effects. Since most of the results have been derived from non-randomised studies, they are likely to be influenced by potential biases and confounding factors. There is currently insufficient supporting evidence to justify the routine implementation of care pathways for acute stroke management or stroke rehabilitation.

Critical Pathways↗
PubMed2001

Development and connectivity of olfactory pathways in the brain of the lobster Homarus americanus.

The main output pathways from the olfactory lobes (primary olfactory centers) and accessory lobes (higher-order integrative areas) of decapod crustaceans terminate within both of the main neuropil regions of the lateral protocerebrum: the medulla terminalis and the hemiellipsoid body. The present study examines the morphogenesis of the lateral protocerebral neuropils of the lobster, Homarus americanus, and the development of their neuronal connections with the paired olfactory and accessory lobes. The medulla terminalis was found to emerge during the initial stages of embryogenesis and to be the target neuropil of the output pathway from the olfactory lobe. In contrast, the hemiellipsoid body is first apparent during mid-embryonic development and is innervated by the output pathway from the accessory lobe. The dye injections used to elucidate these pathways also resulted in the labeling of a previously undescribed pathway linking the olfactory lobe and the ventral nerve cord. To increase our understanding of the morphology of the olfactory pathways in H. americanus we also examined the connectivity of the lateral protocerebral neuropils of embryonic lobsters. These studies identified several interneuronal populations that may be involved in the higher-order processing of olfactory inputs. In addition, we examined the neuroanatomy of ascending pathways from the antenna II and lateral antenna I neuropils (neuropils involved in the processing of chemosensory and tactile inputs). These studies showed that the ascending pathways from these neuropils innervate the same regions of the medulla terminalis and that these regions are different from those innervated by the olfactory lobe output pathway.

Animals↗
PubMed1988

Ultrastructural characterization of the synapses of the crossed temporodentate pathway in rats.

The present study was undertaken to define the ultrastructure of synapses of the crossed temporodentate pathway from the entorhinal cortex to the contralateral dentate gyrus and to compare the synapses of the sparse crossed pathway with those of the massive ipsilateral temporodentate pathway. The synapses of the crossed pathway were identified by using EM degeneration and EM autoradiographic techniques. For the degeneration studies, adult male Sprague-Dawley rats were killed 1, 2, or 4 days following a unilateral entorhinal cortex lesion and prepared for electron microscopy. To identify the synapses by using autoradiographic techniques, four animals received injections of 3H-proline into the entorhinal cortex, were allowed to survive for 3 days, and were prepared for EM autoradiography. Degenerating synapses of the crossed pathway that were found in the molecular layer of the dentate gyrus contralateral to a lesion formed asymmetric synapses on spines and possessed presynaptic organelles indistinguishable from synapses of the ipsilateral temporodentate pathway. The number of degenerating synapses was very low at all survival intervals (14.80 degenerating synapses/10,000 microns2 at 1 day postlesion and 1.95 degenerating synapses/10,000 microns2 at 2 days postlesion); no degenerating synapses were found at 4 days postlesion. Ninety-eight percent of the degenerating synapses found at 1 day postlesion exhibited electron-lucent degeneration. At 2 days postlesion 83% of the degenerating synapses in the dorsal blade and 18% of those in the ventral blade showed lucent degeneration; the remainder were electron dense. EM autoradiography confirmed the degeneration studies in terms of the type of terminals that were labeled and suggested that the density of the crossed pathway was higher than the degeneration results implied. We conclude that synapses of the crossed temporodentate pathway have a similar ultrastructure to synapses of the ipsilateral temporodentate pathway but exhibit a rapid form of degeneration such that they disappear very rapidly following the lesion.

Animals↗
PubMed1988

Connections of the dorsal nucleus of the lateral lemniscus: an inhibitory parallel pathway in the ascending auditory system?

This study examines the dorsal nucleus of the lateral lemniscus (DNLL) and its afferent and efferent connections. In Nissl-stained material, DNLL has three parts: dorsal, ventral, and lateral. Although each part contains neurons with similar Nissl patterns, the subdivisions may be distinguished by the size, shape, and orientation of the cells. The lateral DNLL contains a mixture of DNLL neurons and cells from the sagulum. Afferent connections to DNLL were investigated with anterograde axonal transport techniques. Bilateral inputs to DNLL arise from the anteroventral cochlear nucleus and lateral superior olive, while unilateral inputs are provided by the ipsilateral medial superior olive and the contralateral DNLL. The inputs appear to have a tonotopic organization. Afferent fibers to DNLL form horizontal bands that are continuous both mediolaterally and rostrocaudally. All parts of DNLL do not share the same inputs, and a medial-to-lateral gradient in the labeling of some pathways is evident. To study the efferent connections of DNLL, both retrograde and anterograde axonal transport techniques were used. The DNLL projects to the inferior colliculus and the contralateral DNLL. The topography of these projections suggests that areas of similar tonotopic organization are connected. In the inferior colliculus, the projection is heaviest to the central nucleus and extends to the adjacent dorsal and caudal cortex, the rostral pole nucleus, and the ventrolateral nucleus. Axons from DNLL terminate along the fibrodendritic laminae of the central nucleus as bands that are prominent on the contralateral side, whereas those on the ipsilateral colliculus are more diffuse. The afferent and efferent connections of DNLL constitute a multisynaptic pathway, parallel to the other ascending pathways to the inferior colliculus. The other ascending pathways include the direct pathways from the cochlear nucleus to the inferior colliculus and the indirect pathways via the superior olivary complex. Ascending pathways are discussed as to their relationship to the subdivisions of the inferior colliculus, the laterality of their projections, and their banding patterns in the central nucleus. In contrast to the excitatory pathways to the inferior colliculus, the neurons in DNLL may use GABA as a neurotransmitter. Axons from the DNLL terminate in the inferior colliculus as bands that could have a unique inhibitory function. Thus, the multisynaptic, DNLL pathway may provide feed-forward inhibitory inputs to the inferior colliculus, bilaterally, and to the contralateral DNLL.

Animals↗
PubMed1987

Reflex pathways from group II muscle afferents. 1. Distribution and linkage of reflex actions to alpha-motoneurones.

The interneuronally mediated reflex actions evoked by electrical stimulation of group II muscle afferents in low spinal cats have been reinvestigated with intracellular recording with motoneurones to knee flexors and ankle extensors. The results of Eccles and Lundberg (1959) have been confirmed and extended. There was wide convergence from flexors and extensors of group II excitation to flexor and group II inhibition to extensor motoneurones. Some quantitative differences in the effect from the different nerves are described. Latency measurements suggest that the minimal linkage is disynaptic in the excitatory interneuronal pathways and trisynaptic in the inhibitory pathways. Disynaptic group II EPSPs were found in 14% of the ankle extensor motoneurones but were much more common in unanaesthetized high spinal cats (Wilson and Kato 1965). From these results and corresponding ones on flexors (Holmqvist and Lundberg 1961) it is postulated that secondary afferents in addition to the weak monosynaptic connexions (Kirkwood and Sears 1975) have disynaptic excitatory pathways and trisynaptic inhibitory pathways to both flexor and extensor motoneurones. It is proposed that the group II actions of the flexor reflex pattern characterizing the anaesthetized low spinal cat are due to suppression of the inhibitory pathway to flexor motoneurones and the excitatory pathway to extensor motoneurones. In some ankle extensor motoneurones the disynaptic group II EPSPs occurred in combination with IPSPs from the FRA (including group II and III muscle afferents). The possibility is considered that these group II EPSPs are mediated by an interneuronal group II pathway with little or no input from group III muscle afferents but probably from extramuscular receptors. In other ankle extensor motoneurones group II EPSPs were combined with EPSPs from group III muscle afferents, cutaneous afferents and joint afferents. It is postulated that these group II EPSPs are mediated by an interneuronal pathway from the FRA which also supply interneuronal pathways giving inhibition to extensor or/and flexor motoneurones and excitation to flexors as postulated by Eccles and Lundberg (1959) and Holmqvist and Lundberg (1961).

Animals↗
PubMed1976

Integration in descending motor pathways controlling the forelimb in the cat. 2. Convergence on neurones mediating disynaptic cortico-motoneuronal excitation.

With intracellular recording from forelimb motoneurones the spatial facilitation technique has been used to investigate interaction between descending pathways and forelimb afferents. As previously shown for the hindlimb, pyramidal volleys effectively facilitate interneuronal transmission in reflex pathways from different primary afferents. Evidence is presented suggesting disynaptic excitation from corticospinal fibres of interneurones in the reciprocal Ia inhibitory pathway. Interneurones of other reflex pathways from group I muscle afferents recieve monosynaptic pyramidal excitation. During pyramidal facilitation volleys in cutaneous afferents may evoke PSPs in motoneurones after a central delay of 1.3 ms suggesting that the minimal linkage is disynaptic. Information regarding convergence on the neurones intercalated in the disynaptic cortico-motoneuronal pathway was obtained by investigating the effect from primary afferents and from other descending pathways on the disynaptic pyramidal EPSPs. Volleys in cutaneous and group I muscle affferents facilitate transmission in the disynaptic cortico-motoneuronal transmission with a time course showing oligosynaptic (probably monosynaptic) action the intercalated neurone. Rubrospinal volleys likewise effectively facilitate disynaptic cortico-motoneuronal pathway with a time course showing oligosynaptic (probably monosynaptic) action on the intercalated neurone. Rubrospinal volleys likewise effectively facilitate disynaptic cortico-motoneuronal transmission with a time course showing monosynaptic action on the intercalated neurone. Spatial facilitation experiments involving three tests revealed that those intercalated neurones which receive convergent monosynaptic excitation from corticospinal and rubrospinal fibres are excited also from cutaneous forelimb afferents. Disynaptic cortico-motoneuronal transmission was also monosynaptically facilitated by stimuli in the dorsal mesencephalic tegmentum probably activating tectospinal fibres. Disynaptic, presumed tectospinal EPSPs were facilitated from cutaneous forelimb afferents. The convergence onto the neurones intercalated in the disynaptic excitatory cortico-motoneuronal pathway suggests that these neurones integrate the activity in different descending pathways and primary forelimb afferents.

Animals↗
PubMed2000

Improvement of health outcomes after continued implementation of a clinical pathway for radical nephrectomy.

The clinical pathway is an important tool for outcome management. We evaluated the overall effects of the continued implementation of a clinical pathway for radical nephrectomy on the length of hospital stay, admission charges, and the quality of medical care. The data obtained from the second-year implementation (group 3) of the clinical pathway were compared with the data from the first-year implementation (group 2) and the year preceding implementation (group 1). Thirty-seven consecutive patients with renal cell carcinoma underwent radical nephrectomy in group 1, 47 in group 2, and 55 in group 3; all were enrolled in this study. The length of hospital stay, average admission charges, and 8 quality indicators were measured in these patients. We also evaluated the variances in the implementation of the clinical pathway. The mean length of stay decreased by 14.0% (P = 0.0048) in group 2, and by 15.8% (P= 0.0014) in group 3, when compared to group 1. The total admission charges significantly decreased by 19.0% (P = 0.001) in group 2, and by 27.9% (P < 0.0001) in group 3, compared to the charges for group 1. A continued decrease in charges for operation and anesthesia, laboratory, pharmacy, and others were found 2 years after implementation of the clinical pathway. Among the 8 quality indicators, 2 were continuously improved in the second-year implementation of the clinical pathway, 2 were improved significantly in the second-year implementation only, and 4 showed no significant change at all. Variances from the clinical pathway decreased significantly after continued implementation. Continued implementation of the clinical pathway for radical nephrectomy can improve a physician's practice continuously by decreasing the length of hospital stay, admission charges, and variances, and by improving quality. However, the improved results after implementation of the clinical pathway should be maintained carefully to assure good health care.

Adult↗
PubMed2000

Cost and utilization impact of a clinical pathway for patients undergoing pancreaticoduodenectomy.

BACKGROUND: When implemented in several common surgical procedures, clinical pathways have been reported to reduce costs and resource utilization, while maintaining or improving patient care. However, there is little data to support their use in more complex surgery. The objective of this study was to determine the effects of clinical pathway implementation in patients undergoing elective pancreaticoduodenectomy (PD) on cost and resource utilization. METHODS: Outcome data from before and after the development of a clinical pathway were analyzed. The clinical pathway standardized the preoperative outpatient care, critical care, and postoperative floor care of patients who underwent PD. An independent department determined total costs for each patient, which included all hospital and physician costs, in a blinded review. Outcomes that were examined included perioperative mortality, postoperative morbidity, length of stay, readmissions, and postoperative clinic visits. RESULTS: From January, 1996 to December, 1998, 148 consecutive patients underwent PD or total pancreatectomy; 68 before pathway development (PrePath) and 80 after pathway implementation (PostPath). There were no significant differences in patient demographics, comorbid conditions, underlying diagnosis, or use of neoadjuvant therapy between the two groups. Mean total costs were significantly reduced in PostPath patients compared with PrePath patients ($36,627 vs. $47,515; P = .003). Similarly, mean length of hospital stay was also significantly reduced in PostPath patients (13.5 vs. 16.4 days; P = .001). The total cost differences could not be attributed solely to differences in room and board costs. Cost and length-of-stay differences remained when outliers were excluded from the analysis. Despite these findings, there were no significant differences between PrePath and PostPath patients in terms of perioperative mortality (3% vs. 1%), readmissions within 1 month of discharge (15% vs. 11%), or mean number of clinic visits within 90 days of discharge (3.3 vs. 3.4 visits). CONCLUSIONS: The establishment of a clinical pathway for PD patients dramatically reduced costs and resource utilization without any apparent detrimental effect on quality of patient care. These findings support the implementation of clinical pathways for PD patients, as well as investigation into pathway care for other complex surgical procedures.

Aged↗
PubMed1990

Cerebellotectal pathways in the macaque: implications for collicular generation of saccades.

The cerebellum is thought to modulate saccadic activity in the primate in order to maintain targeting accuracy, and the cerebellotectal pathway has been posited to play a role in this modulation. However, anatomical descriptions of this pathway in primates are sketchy and conflicting. To determine whether the organization of the cerebellotectal projection in primates is similar to that found in other species, neuroanatomical tracer transport techniques were utilized in two species of macaque monkey to label cerebellotectal somata and fiber terminations. Two pathways were found. One, the fastigiotectal pathway, is derived from cells in the caudal fastigial nucleus and projects bilaterally to the rostral end of the intermediate gray layer. The other pathway is derived from cells in the posterior interposed nucleus and the adjacent posterior wing of the dentate nucleus, and it terminates contralaterally throughout the ventral half of the intermediate gray and the deep gray layers. Both of these pathways terminate within the layers of the superior colliculus containing premotor, saccade-related neurons, but the differences in the distribution of their terminals and cells of origin suggest that these two pathways have different functions. Furthermore, the pattern of connections of these two pathways indicates that they do not function as a traditional feedback circuit. We suggest that the cerebellotectal pathways may instead modulate collicular activity in a more complex manner. For example, it may provide signals necessary for corrective saccades or for maintaining spatial registry between the different sensory representations supplied to the superior colliculus and its presaccadic output, which is organized into a motor map.

Animals↗
PubMed2026

Accelerated Diagnostic Pathways for Suspected Acute Coronary Syndrome in Practice: A Randomized Trial of 0/1-Hour vs 0/3-Hour Troponin Testing.

BACKGROUND: For suspected acute coronary syndrome (ACS), guidelines recommend using high-sensitivity troponins (hs-cTn) in accelerated diagnostic pathways (ADPs) with 0/1-hour recommended over 0/3-hour ADP. However, implementation of these ADPs, with universal use of hs-cTns, has not been directly compared in randomized trials OBJECTIVES: This study sought to compare the efficiency and safety of the European Society of Cardiology (ESC) 0/1-hour and a 0/3-hour ADP when implemented in real-world clinical practice. METHODS: This pragmatic, randomized, noninferiority implementation trial compared the safety and efficiency of clinician decision making using these 2 pathways. To prevent incorporation bias, an independent hs-cTnI was used for formal adjudication using the fourth universal definition of myocardial infarction (MI). Efficiency was judged by the proportion of patients discharged within 4 hours. The safety endpoint was major adverse cardiac events (MACE) within 30 days (adjudicated index or representation type 1 MI, cardiovascular death, and urgent coronary revascularization) for those who were considered not to have ACS and discharged. The noninferiority margin, for absolute difference in sensitivity, between the ESC 0/1-hour and the 0/3-hour ADP was set at 3%, assessed with a 1-sided 97.5% CI. RESULTS: From December 2021 to July 2024, of 13,983 screened 3,543 individual patients with suspected ACS were recruited and consented from 2 major emergency departments in North-West England, with 100% follow-up achieved for all representations to any national hospital. The median age was 60 years (IQR: 49.5-70.5 years), 53% were men, 6.7%, and 7.6% had adjudicated index type 1 MI and MACE within 30 days, respectively. The turnaround time from sample to result for central laboratory hs-cTnT was 81 minutes (IQR: 69-101 minutes). The proportion of patients discharged within 4 hours was relatively low and did not differ substantially (21.8% vs 19.2%, P = 0.07). In addition, the 0/1-hour pathway was noninferior for safety, in patients discharged, compared with the 0/3-hour pathway, absolute difference in sensitivity was +4.2% (1-sided 97.5% CI: -2.5) in favor of the 0/1-hour pathway. The calculated sensitivities were 93.7% (95% CI: 88.4%-97.1%) vs 89.5% (95% CI: 82.7%-94.3%), respectively. CONCLUSIONS: Implementation of the ESC 0/1-hour pathway failed to discharge significantly more patients within 4 hours of presentation compared with the 0/3-hour ADP. In addition, The ESC 0/1-hour was noninferior to the 0/3-hour hs-cTn pathway for safety of discharge, although safety for both pathways was less than that imputed by observational studies. This trial demonstrates that perceived benefits to emergency department efficiency of a reduced sampling interval are mitigated by central laboratory turnaround times as well as system constraints. (Pragmatic Randomised Trial of the ESC 0/&#x200b;1 Versus 0/&#x200b;3 Hour Troponin Pathway [MACROS2]; NCT05322395).

Acute Coronary Syndrome↗
PubMed2006

Investigation of Lewy pathology in the visual pathway of brains of dementia with Lewy bodies.

We examined 19 autopsied cases of dementia with Lewy bodies (DLB) using pathological and alpha-synuclein-immunohistochemical methods, and investigated Lewy pathology in the primary visual pathway (lateral geniculate body and Brodmann's area 17), secondary visual pathway (pulvinar, Brodmann's areas 18 and 19, and inferior temporal cortex), amygdala and substantia nigra, to clarify the relationship between visual misidentification and Lewy pathology in the visual pathway. Consequently, the secondary visual pathway revealed significantly severer Lewy pathology than the primary visual pathway, suggesting that the degeneration of the secondary visual pathway induces dysfunction in the recognition of objects shape and color. In addition, the amygdala revealed significantly severer Lewy pathology and neuronal loss than the primary and secondary visual pathways, suggesting that the degeneration of the amygdala, which receives the afferent connections from the substantia nigra, fails to modulate the visual processing according to cognition and emotion. These findings suggest that Lewy pathologies in the secondary visual pathway and amygdala may cause the dysfunction of the visuo-amygdaloid pathway and participate in visual misidentification in DLB patients. In addition, we compared Lewy pathology between cases with and without visual hallucinations, and showed no significant differences between the two groups.

Aged↗
PubMed2001

Critical pathways intervention to reduce length of hospital stay.

PURPOSE: Despite their popularity, critical pathways have been evaluated in only a few controlled studies. We evaluated the effectiveness of critical pathways in reducing length of hospital stay. SUBJECTS AND METHODS: We compared postoperative lengths of stay of patients who underwent coronary artery bypass graft (CABG) surgery, total knee replacement, colectomy, thoracic surgery, or hysterectomy before and after pathway implementation at a university hospital. For three procedures, changes in lengths of stay at neighboring hospitals without pathway programs were assessed for comparison. RESULTS: A total of 6,796 patients underwent one of the procedures during the study. The percentage of eligible patients managed on a critical pathway ranged from 94% for hysterectomy to 26% for colectomy. For most procedures, the postoperative length of stay was decreasing during the baseline period. After pathway implementation, the length of stay decreased 21% for total knee replacement, 9% for CABG surgery, 7% for thoracic surgery, 5% for hysterectomy, and 3% for colectomy (all P < 0.01). However, similar decreases were seen in the neighboring hospitals that did not have critical pathways or other specific efficiency initiatives. CONCLUSIONS: Critical pathways were associated with a rapid reduction in postoperative length of stay after all five study procedures. Secular trends at nearby hospitals, however, produced comparable reductions for the three procedures available for comparison. These findings raise questions about the effectiveness of critical pathways in a competitive environment.

Adult↗
PubMed1996

Alternative pathway of complement in ruminants: role in infection.

Besides being initiated by antigen-antibody complexes, the classical pathway also can be activated by two innate mechanisms: (1) A family of proteins called collectins, which resemble C1q, bypass the activation of C1q. (2) Acute phase proteins, belonging to the family of pentraxins, activate the classical pathway by binding to C1q. The term 'alternative' complement pathway is a misnomer. This system is a primary primitive immune mechanism. It is phylogenetically older than the classical pathway. Contrary to the classical pathway, it does not require development of a specific immune response before getting into action. It acts within minutes after the microorganism has entered the body. The alternative pathway is continually activated at a low controlled rate but amplified by the surface of intruding microorganisms. It has the capacity to distinguish between self and non-self. Many nonpathogenic microorganisms are killed by the alternative pathway of complement. Pathogens have developed evasion mechanisms to escape the killing effect of this pathway. The kinetics of the activation of the alternative pathway of ruminants differs from that of mouse and man. The difference might be mediated by conglutinin.

Animals↗
PubMed2003

Membrane properties of identified lateral and medial perforant pathway projection neurons.

The physiological characteristics of neurons that project to the hippocampus and dentate gyrus via the medial perforant pathway (projection neurons) are well known, but the characteristics of neurons that project to these areas via the lateral perforant pathway (projection neurons) are less well known. We have used retrograde tracing and whole-cell recording in brain slices to compare the membrane and firing properties of medial perforant pathway and lateral perforant pathway projection neurons in layer II of the medial and lateral entorhinal cortex. The properties of medial perforant pathway projection neurons were identical to those reported previously for spiny stellate neurons in the medial entorhinal cortex. In contrast, lateral perforant pathway projection neurons were characterized by a higher input resistance, a lack of time-dependent inward (anomalous) rectification, and a lack of prominent depolarizing spike afterpotentials. Voltage-clamp recordings suggest that the absence of anomalous rectification in lateral perforant pathway projection neurons is due to smaller hyperpolarization activated cation currents in these cells, and the lack of depolarizing afterpotential may be due to smaller low-threshold calcium currents. Persistent sodium current was also smaller in lateral perforant pathway projection neurons, but the difference in persistent sodium current between medial perforant pathway and lateral perforant projection neurons was much less pronounced than the difference in low voltage activated currents. These results underscore the functional differences between the medial entorhinal cortex and lateral entorhinal cortex, and may help to explain the differing abilities of these cortical areas to participate in certain types of network activity.

Action Potentials↗
PubMed1998

Benchmarking the perioperative process: II. Introducing anesthesia clinical pathways to improve processes and outcomes and to reduce nursing labor intensity in ambulatory orthopedic surgery.

STUDY OBJECTIVES: (1) To introduce anesthesia clinical pathways as a management tool to improve the quality of care; (2) to use the Procedural Times Glossary published by the Association of Anesthesia Clinical Directors (AACD) as a template for data collection and analysis; and (3) to determine the effects of anesthesia clinical pathways on surgical processes, outcomes, and costs in common ambulatory orthopedic surgery. DESIGN: Hospital database and patient chart review of consecutive patients undergoing anterior cruciate ligament reconstruction (ACLR) during academic years (AY) 1995-1996 and 1996-1997. Patient data from AY 1995-1996, during which no intraoperative anesthesia clinical pathways existed, served as historical controls. Data from AY 1996-1997, during which intraoperative anesthesia clinical pathways were used, served as the treatment group. Regional anesthesia options were routinely offered to patients in the clinical pathway. SETTING: Ambulatory surgery center in a teaching hospital. MEASUREMENTS AND MAIN RESULTS: The records of 503 ASA physical status I and II patients were reviewed. 1996-1997 patients underwent clinical pathway anesthesia care in which the intraoperative and postoperative anesthesia process was standardized with respect to symptom management, drugs, and equipment used. 1995-1996 patients did not have a standardized intraoperative and postoperative anesthetic course with respect to the management of common symptoms or to specific drugs and supplies used. Intervals described in the AACD Procedural Times Glossary, anesthesia drug and supply costs, and patient outcome variables (postoperative nursing interventions required and unexpected admissions), as influenced by the use of the anesthesia clinical pathway, were measured. Clinical pathway anesthesia care of ACLR in 1996-1997, which actively incorporated regional anesthesia options, reduced pharmacy and materials cost variability; slightly increased turnover time; improved intraoperative anesthesia and surgical efficiency, recovery times, and unexpected admission rates; and decreased the number of required nursing interventions for common postoperative symptoms. CONCLUSIONS: Clinical pathway patient management systems in anesthesia care are likely to produce useful outcome data of current practice patterns when compared with historical controls. This management tool may be useful in simultaneously containing costs and improving process efficiency and patient outcomes.

Adult↗
PubMed1997

Functional anatomy of neural pathways contributing to the control of song production in birds.

In birds, as in humans, vocal control involves the intricate coordination of three major groups of muscles, namely, those of the vocal organ, the respiratory apparatus, and the vocal tract, including the jaw and tongue. The neural pathways involved in the control of each of these groups of muscles are described for songbirds and compared with those in non-oscine birds and mammals. The pathway in songbirds that controls the syrinx, the bird's vocal organ, originates in the telencephalon and projects via the occipito-mesencephalic tract directly upon vocal motoneurons in the medulla. Activity in this pathway configures the syrinx into phonatory positions for the production of species typical vocalizations. Another component of this pathway mediates control of respiration during vocalization, since it projects upon both expiratory and inspiratory groups of premotor neurons in the ventrolateral medulla, as well as upon several other nuclei en route. This pathway appears to be primarily involved with the control of the temporal pattern of song, but is also importantly involved in the control of vocal intensity, mediated via air sac pressure. There are extensive interconnections between the vocal and respiratory pathways, especially at brainstem levels, and it may be these that ensure the necessary temporal coordination of syringeal and respiratory activity. The pathway mediating control of the jaw appears to be different from those mediating control of the syrinx and respiratory muscles. It originates in a different part of the telencephalon and projects upon premotor neurons in the medulla that, on preliminary analysis, appear to be separate from those projecting upon the syringeal motor nucleus. The separateness of this pathway may reflect the imperfect correlation of jaw movements with the dynamic and acoustic features of song. The brainstem pathways mediating control of vocalization and respiration in songbirds have distinct similarities to those in non-oscine birds and in mammals such as cats and monkeys. However, songbirds and parrots, like humans, but unlike other non-songbirds, have developed a special telencephalic vocal control system for the production of learned vocalizations.

Animals↗
PubMed1979

Lysis of measles virus-infected cells by the purified cytolytic alternative complement pathway and antibody.

The dependence of antibody-and-complement-mediated lysis of virus-infected cells on the alternative pathway was examined utilizing the isolated cytolytic alternative pathway--a system consisting of the six purified proteins of the alternative pathway of activation (C3, factors B and D, beta 1H, C3b inactivator and properdin), and the five proteins of the membrane attack pathway (C5--9) of complement. HeLa cells acutely infected with measles virus were lysed by anti-viral IgG and the isolated cytolytic alternative pathway with an efficiency comparable to whole human serum. IgG and its F(ab')2 fragment were equally effective in inducing lysis by the isolated cytolytic alternative pathway, binding of approximately equal to 5 X 10(7) molecules per cell being required for 50% lysis; in contrast, no lysis occurred when equivalen or greater amounts of Fab' were bound to the virus-infected cell. Properdin was required for lysis. No lysis occurred if properdin was deleted from the isolated cytolytic alternative pathway, and lysis was diminished by 80% in properdin-depleted serum. Uptake of [125I]C3b from the isolated alternative pathway onto measles virus-infected cells occurred in the absence of properdin, but was accelerated in the presence of properdin. The 11 proteins of the isolated cytolytic alternative pathway are thus sufficient for lysis of measles virus-infected cells bearing anti-viral IgG or F(ab')2 without any other serum protein.

Antibodies, Viral↗
PubMedDate not supplied

Functional development of the corticocortical pathway for motion analysis in the macaque monkey: a 14C-2-deoxyglucose study.

The corticocortical pathway for motion analysis transmits visual information from striate cortex (V1) via V2, V3d, superior temporal sulcal areas MT, MST, and FST to motion-sensitive areas in the floor and upper bank of the anterior part of the superior temporal sulcus (AST). We studied the functional development of this pathway by applying the 14C-2-deoxyglucose method to rhesus monkeys (Macaca mulatta) ranging in age from 2 d to 3-4 years. A comparison of local cerebral glucose utilization (LCGU) in an intact and a visually deafferented hemisphere in each animal across the age range revealed that this pathway, immature at birth, reaches adult-like levels at 3 months of age. This developmental time course is reflected both in absolute LCGU and in the interhemispheric LCGU differences in all the areas of the pathway. At all ages, the interhemispheric difference in LCGU is largest in V1 and gradually declines along the pathway until a minimum is reached in AST. This decline likely reflects an increasing proportion of nonvisual inputs to the higher-order areas of the pathway. Measurements like those above taken in areas of inferior parietal cortex indicate that they mature at the same rate as those in the motion analysis pathway. However, comparison with findings on the functional development of the temporal areas of the occipitotemporal pathway for object vision (Bachevalier et al., 1991) suggests that areas along the motion analysis pathway and those in parietal cortex mature about 1 month earlier.

Age Factors↗