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Understanding rural and remote divisions under a workforce framework.

In Australia, divisions of general practice are the organisational structures for local networks of general practitioners. They facilitate communication across the profession and with other parts of the health system and are established in urban, rural and remote areas. Funding is provided contractually to divisions through the Federal Government's Divisions and Projects Grants Program. The under-supply of doctors and other health professionals in rural and remote areas of Australia is a serious problem that has far-reaching effects. The present paper argues that if the Divisions and Projects Grants Program is to be effective in achieving its aims and objectives, then the Program's policies must be responsive to the different needs, roles, constraints, expectations and capabilities of divisions and their members as well as the structural impediments imposed by the medical workforce.

Australia↗

[Uveal melanoma].

The paper present a clinic and histological study, including all cases of uveal malignant tumours, hospitalized in Ophthalmological Clinic of Craiova in the last 15 years. The follow-up period of cases were 4 years. The diagnosis was established by clinic and paraclinic examination (imaging methods-- MRI, CT, Echo) and histologic examination. The histologic examination has been done for all cases. There were investigated several parametres: tumour cytology, the level of pigmentation, intravascular embolus, sclera infiltration, vascular invasion, vascular pattern, tumoral necrosis, mitotic activity. The histologic aspects of tumoral progression were: the high level mitotic activity, high surface area of intratumoral necrosis, the infiltrative process to the vessels, sclera, and ciliary body. The arcuat and network vascular patterns were involved in the systemic metastasis and local invasion. The most predominant type of cellularity related with a severe evolution of cases were the epithelioid cells and the mixed type cells.

Adult↗

Localization of melanin-concentrating hormone-like immunoreactivity in the brain and pituitary of the frog Rana ridibunda.

The distribution of melanin-concentrating hormone (MCH) in the central nervous system of the frog Rana ridibunda was determined by the indirect immunofluorescence technique using antibodies against synthetic salmon MCH, generated in rabbits. The most prominent group of MCH-like containing perikarya was detected in the preoptic nucleus. Comparatively, a moderate number of cell bodies was observed in the dorsal infundibular nucleus and in the ventral thalamic area. Brightly immunofluorescent nerve bundles were found in the preoptic nucleus and in the ventral infundibular nucleus, coursing towards the internal zone of the median eminence and the pituitary stalk. An intense network of immunofluorescent fibers was localized in the neural lobe of the pituitary. The subcellular localization of MCH-like material was studied in the neurohypophysis using the immunogold technique. It was demonstrated that MCH-like material was contained in dense core vesicles (80-90 mm in diameter) within specific nerve terminals. The present findings indicate that, in amphibians, MCH-like peptide is located in specific hypothalamic neurons. Our data suggest that MCH may be released by neurohypophyseal nerve endings as a typical neurohormone.

Animals↗

Spatiotemporal patterns of dorsal root-evoked network activity in the neonatal rat spinal cord: optical and intracellular recordings.

Spatiotemporal patterns of dorsal root-evoked potentials were studied in transverse slices of the rat spinal cord by monitoring optical signals from a voltage-sensitive dye with multiple-photodiode optic camera. Typically, dorsal root stimulation generated two basic waveforms of voltage images: dual-component images consisting of fast, spike-like signal followed by a slow signal in the dorsal horn, and small, slow signals in the ventral horn. To qualitatively relate the optical signals to membrane potentials, whole cell recordings were combined with measurements of light absorption in the area around the soma. The slow optical signals correlated closely with subthreshold postsynaptic potentials in all regions of the cord. The spike-like component was not associated with postsynaptic action potentials, suggesting that the fast signal was generated by presynaptic action potentials. Firing in a single neuron could not be detected optically, implying that local voltage images originated from synchronously activated neuronal ensembles. Blocking glutamatergic synaptic transmission inhibited excitatory postsynaptic potentials (EPSPs) and significantly reduced the slow optical signals, indicating that they were mediated by glutamatergic synapses. Suppressing glycine-mediated inhibition increased the amplitude of both optical signals and EPSPs, while blocking GABA(A) receptor-mediated synapses, increased the amplitude and time course of EPSPs and prolonged the duration of voltage images in larger areas of the slice. The close correlation between evoked EPSPs and their respective local voltage images shows the advantage of the high temporal resolution optical system in measuring both the spatiotemporal dynamics of segmental network excitation and integrated potentials of neuronal ensembles at identified sites.

2-Amino-5-phosphonovalerate↗

Hypothalamic resistin immunoreactivity is reduced by obesity in the mouse: co-localization with alpha-melanostimulating hormone.

Resistin is a new adipokine expressed in mouse, rat and human adipose tissue. Resistin may be an important link between obesity and insulin resistance, though this controversial view is complicated by the discovery of multiple sites of resistin expression, including human macrophages, placenta and pancreas. In previous studies we demonstrated that the mouse hypothalamo-pituitary system was also a site of resistin production. Pituitary resistin is developmentally regulated, reduced in the ob/ob mouse and severely down-regulated by food deprivation (24 h). An unexpected finding was that hypothalamic resistin mRNA remained unaffected by fasting. The present experiments examined the localization and possible regulation of hypothalamic resistin protein. Using immunohistochemistry we observed a complex network of resistin+ fibres extending rostrally from the arcuate nucleus of the hypothalamus (ARC) to the preoptic area. Labelled cell bodies occurred only in the ARC and in a periventricular region of the dorsal hypothalamus. Hypothalamic resistin immunoreactivity (ir) was unaffected by fasting (48 h) or by a high fat diet, but the periventricular staining was greatly increased in the lactating mouse. Marked reductions in resistin+ fibres were seen in brain tissue from: (a) ob/ob mice, (b) young mice made underweight for their age by raising them in large litters (20 pups per litter) and (c) mice with hypothalamic lesions induced by monosodium glutamate (MSG) or gold thioglucose (GTG). We speculate that the resistin-ir deficit in genetically obese mice, and in severely underweight mice, could be due to low or absent leptin. In contrast, though MSG- and GTG-treated mice have high levels of circulating leptin, in the presence of excessive visceral fat deposits, we hypothesize that damage to the ARC destroys the resistin+ cell bodies. This latter supposition led us to an additional hypothesis, that resistin-ir would be contained in neurons expressing the proopiomelanocortin (POMC) gene. This proved to be correct. Double label immunofluorescence histochemistry revealed that alpha-MSH-ir, a marker for POMC neurons, was co-localized with resistin-ir. In conclusion, our data reveal a second example of an adipocytokine co-localized with a hypothalamic neuropeptide. We reported previously that leptin was co-localized with oxytocin and vasopressin. RT-PCR analysis confirmed that resistin mRNA is readily detectable in ARC, but further work is required to determine whether the resistin gene is expressed in POMC neurons or if resistin is specifically accumulated by these cells. Nonetheless, our data suggest that the hypothalamus is a target tissue for resistin.

Age Factors↗

A functional glutamatergic neurone network in the medial septum and diagonal band area.

The medial septum and diagonal band complex (MS/DB) is important for learning and memory and is known to contain cholinergic and GABAergic neurones. Glutamatergic neurones have also been recently described in this area but their function remains unknown. Here we show that local glutamatergic neurones can be activated using 4-aminopyridine (4-AP) and the GABA(A) receptor antagonist bicuculline in regular MS/DB slices, or mini-MS/DB slices. The spontaneous glutamatergic responses were mediated by AMPA receptors and, to a lesser extend, NMDA receptors, and were characterized by large, sometimes repetitive activity that elicited bursts of action potentials postsynaptically. Similar repetitive AMPA receptor-mediated bursts were generated by glutamatergic neurone activation within the MS/DB in disinhibited organotypic MS/DB slices, suggesting that the glutamatergic responses did not originate from extrinsic glutamatergic synapses. It is interesting that glutamatergic neurones were part of a synchronously active network as large repetitive AMPA receptor-mediated bursts were generated concomitantly with extracellular field potentials in intact half-septum preparations in vitro. Glutamatergic neurones appeared important to MS/DB activation as strong glutamatergic responses were present in electrophysiologically identified putative cholinergic, GABAergic and glutamatergic neurones. In agreement with this, we found immunohistochemical evidence that vesicular glutamate-2 (VGLUT2)-positive puncta were in proximity to choline acetyltransferase (ChAT)-, glutamic acid decarboxylase 67 (GAD67)- and VGLUT2-positive neurones. Finally, MS/DB glutamatergic neurones could be activated under more physiological conditions as a cholinergic agonist was found to elicit rhythmic AMPA receptor-mediated EPSPs at a theta relevant frequency of 6-10 Hz. We propose that glutamatergic neurones within the MS/DB can excite cholinergic and GABAergic neurones, and that they are part of a connected excitatory network, which upon appropriate activation, may contribute to rhythm generation.

Action Potentials↗

Mandated human services restructuring: a case study in local collaboration from Colorado.

The Colorado State Legislature has undertaken an historic restructuring of human services ranging from child welfare, mental health, and nursing services to substance abuse prevention, institutionalization, and health care financing. Significant steps in this process include an overhaul of child welfare legislation, major revisions to legislation affecting group health insurance policies, and a restructuring of the state departments that provide human services. A Democratic Governor and a Republican-dominated legislature have worked together hand-in-hand, although not always harmoniously, in moving these changes forward. This article examines the statewide restructuring of human services in a case study of how the local planning process was carried out in one region of Colorado. A highlight of the case study is the Working Together survey administered to participants of the planning committee midway through the process and again after the Local Area Plan was developed. In addition, lessons are presented from the process instructive for others considering whether to undertake significant organizational restructuring. The lesson section focuses on the local area planning process and how Colorado may have designed and facilitated a more effective process.

Colorado↗

Methods for parameter identification in oscillatory networks and application to cortical and thalamic 600 Hz activity.

Directed information transfer in the human brain occurs presumably by oscillations. As of yet, most approaches for the analysis of these oscillations are based on time-frequency or coherence analysis. The present work concerns the modeling of cortical 600 Hz oscillations, localized within the Brodmann Areas 3b and 1 after stimulation of the nervus medianus, by means of coupled differential equations. This approach leads to the so-called parameter identification problem, where based on a given data set, a set of unknown parameters of a system of ordinary differential equations is determined by special optimization procedures. Some suitable algorithms for this task are presented in this paper. Finally an oscillatory network model is optimally fitted to the data taken from ten volunteers.

Cerebral Cortex↗

Computer-aided diagnosis of localized ground-glass opacity in the lung at CT: initial experience.

The purpose of this study was to develop an automated scheme to facilitate detection of localized ground-glass opacity (GGO) in the lung at computed tomography (CT). Institutional review board approval and informed consent were not required. Two radiologists reviewed CT images from 14 patients (five men, nine women) who had lung cancer or metastasis and whose malignancy was classified as GGO. The lung region was sampled and completely covered with contiguous, 50% overlapping regions of interest (ROIs) measuring 30 x 30 pixels in size. The lung area within each ROI was analyzed to compute texture features and gaussian curve fitting features. Performance of the artificial neural networks (ANNs) measured by using the area under the receiver operating characteristic curve was 0.92. With a threshold of 0.9, the sensitivity of the ANN for detecting GGO ROIs was 94.3% (280 of 297 ROIs), and the positive predictive value was 29.1% (280 of 963 ROIs). A computerized scheme may hold promise in facilitating detection of localized GGO at CT.

Aged↗

Cortical neurons that localize sounds.

Efforts to locate a cortical map of auditory space generally have proven unsuccessful. At moderate sound levels, cortical neurons generally show large or unbounded spatial receptive fields. Within those large receptive fields, however, changes in sound location result in systematic changes in the temporal firing patterns such that single-neuron firing patterns can signal the locations of sound sources throughout as much as 360 degrees of auditory space. Neurons in the cat's auditory cortex show accurate localization of broad-band sounds, which human listeners localize accurately. Conversely, in response to filtered sounds that produce spatial illusions in human listeners, neurons signal systematically incorrect locations that can be predicted by a model that also predicts the listeners' illusory reports. These results from the cat's auditory cortex, as well as more limited results from nonhuman primates, suggest a model in which the location of any particular sound source is represented in a distributed fashion within individual auditory cortical areas and among multiple cortical areas.

Animals↗

Sleep-waking discharge patterns of median preoptic nucleus neurons in rats.

Several lines of evidence show that the preoptic area (POA) of the hypothalamus is critically implicated in the regulation of sleep. Functionally heterogeneous cell groups with sleep-related discharge patterns are located both in the medial and lateral POA. Recently a cluster of neurons showing sleep-related c-Fos immunoreactivity was found in the median preoptic nucleus (MnPN). To determine the specificity of the state-related behaviour of MnPN neurons we have undertaken the first study of their discharge patterns across the sleep-waking cycle. Nearly 76 % of recorded cells exhibited elevated discharge rates during sleep. Sleep-related units showed several distinct types of activity changes across sleep stages. Two populations included cells displaying selective activation during either non-rapid eye movement (NREM) sleep (10 %) or REM sleep (8 %). Neurons belonging to the predominant population (58 %) exhibited activation during both phases of sleep compared to wakefulness. Most of these cells showed a gradual increase in their firing rates prior to sleep onset, elevated discharge during NREM sleep and a further increase during REM sleep. This specific sleep-waking discharge profile is opposite to that demonstrated by wake-promoting monoaminergic cell groups and was previously found in cells localized in the ventrolateral preoptic area (vlPOA). We hypothesize that these vlPOA and MnPN neuronal populations act as parts of a GABAergic/galaninergic sleep-promoting ('anti-waking') network which exercises inhibitory control over waking-promoting systems. MnPN neurons that progressively increase activity during sustained waking and decrease activity during sustained sleep states may be involved in homeostatic regulation of sleep.

Action Potentials↗

Enterocutaneous Fistula-Associated Sepsis and Mortality: Development and Validation of a Multimodal Artificial Intelligence Prediction Model.

BACKGROUND: Predicting enterocutaneous fistula (ECF)-associated sepsis and mortality poses significant challenges in digital health care due to the disease's complexity and heterogeneous clinical manifestations. Current approaches that rely on single-modal data or traditional scoring systems often fail to capture the intricate immune-inflammatory dynamics and multisystem involvement in patients with ECF. OBJECTIVE: This study aims to develop an artificial intelligence (AI)-driven multimodal fusion model integrating clinical, imaging, and transcriptomic data for early prediction of ECF-associated sepsis and 28-day mortality, addressing the limitations of conventional single-dimensional models. METHODS: This study leveraged publicly available datasets (Medical Information Mart for Intensive Care III [MIMIC-III], electronic Intensive Care Unit [eICU], and The Cancer Genome Atlas) to construct a multimodal framework. Clinical parameters were processed using Extreme Gradient Boosting, abdominal imaging features were extracted via convolutional neural networks, and transcriptomic profiles were analyzed with variational autoencoders. A Transformer-based fusion network was employed for joint prediction and validated through cross-validation and external testing. Key features were identified using Shapley Additive Explanations and Local Interpretable Model-Agnostic Explanations interpretability algorithms, while immune regulatory mechanisms were explored via weighted gene co-expression network analysis. RESULTS: The multimodal model achieved an area under the curve (AUC) of 0.89 for predicting sepsis and 28-day mortality, outperforming unimodal models (clinical-only model, AUC 0.72, and imaging-only model, AUC 0.78). Critical predictors included Sequential Organ Failure Assessment score, lactate levels, intra-abdominal free fluid on imaging, and immunoregulatory genes (programmed death-ligand 1 [PD-L1] and indoleamine 2,3-dioxygenase 1 [IDO1]). Mechanistic analysis revealed distinct immune reprogramming in patients with sepsis, characterized by increased regulatory T cells and M2 macrophages, along with downregulated cluster of differentiation 8+ (CD8+) T cells. CONCLUSIONS: This multimodal AI model offers an innovative digital solution in medical informatics, enabling precise early risk stratification for ECF-associated sepsis. By integrating multisource data and providing interpretable insights into immune-inflammatory pathways, the model enhances health care quality for patients with ECF and paves the way for personalized intervention strategies.

Humans↗

Localization and characterization of NPY/PYY receptors in rat frontoparietal cortex during development.

Neuropeptide Y (NPY) is present in most cerebrocortical areas during fetal and postnatal development. In the rat frontal cortex, a dense radial fiber network containing NPY immunoreactivity is observed transiently as early as embryonic day 17 (E17) and disappears at the end of the first postnatal week. We have investigated the distribution of NPY receptors in the frontoparietal cortex at 13 stages of development, from E15 fetuses to adults, by in vitro autoradiography, using (125)I-pPYY as a radioligand. Quantitative receptor density was measured through all cortical layers at each developmental stage. Pharmacological identification of (125)I-pPPY binding sites was made by competition experiments using pNPY or [Leu(31),Pro(34)]pNPY and pNPY(13-36), as selective competitors for Y1 and Y2 receptors, respectively. NPY receptors were first detected in the cerebral cortex at low densities at E19 in a thin layer of tissue corresponding to the inner half of the intermediate zone (IZ) and the upper ventricular zone (VZ). The neuroepithelium did not contain binding sites. High densities of sites were observed by E21 onward to P10 in the deep cortical layers corresponding to the IZ and layers V-VI. A decreasing gradient of receptor density was observed from layer VI to the marginal zone (layer I). The distribution of NPY receptors does not match with the perikarya of transient NPY-immunoreactive neurons located in the cortical plate but does coincide with their axonal extension. The receptor density decreased abruptly between P10 and P12 in deep layers, whereas a moderate expression of binding sites is detected from P10 to P12 in layers I-III. By P14, the binding level was the lowest observed in the postnatal period. From P21 onward, receptors were observed in superficial layers I-III, and their density rose by two- to threefold up to adulthood. Competition studies indicated that the NPY receptors located in the deep cortical layers of the E21 or P1 rat cortex exhibit Y2 receptor type characteristics. The binding sites detected in the superficial layers from P10 to P12 rats also show Y2 receptors characteristics, unlike the NPY receptors in layers II-III of the adult, which behave like Y1 receptors. These data show that different NPY receptor types are successively expressed in specific layers during late gestation and early postnatal life in the rat frontoparietal cortex.

Aging↗

The meaning of community in community mental health.

This article critically reviews the development of community mental health in both theory and practice and explores new directions and dilemmas for future policy and programs. First, we trace the dialectical development of the ideology of community mental health and the rediscovery of community. Second, we outline the two key transitions: (a) from professionals to natural helpers and (b) from catchment areas to natural networks. Third, we offer alternative conceptions of community from the sociological literature and suggest ways that these can benefit new program planning. We conclude with a series of policy questions that legitimate the expansion of community mental health beyond the parochial confines of the local community.

Catchment Area, Health↗

The articulatory loop: study of the subcortical connectivity by electrostimulation.

Although a cortical network involving Broca's area and the supramarginal gyrus (SMG) was widely studied using neurofunctional imaging, the functional connectivity underlying this so-called articulatory loop remains poorly documented. We describe a patient operated on for a glioma invading the left parietal operculum, using intraoperative electrical functional mapping under local anesthesia. Following the identification of cortical language sites within Broca's area and SMG, the subcortical pathways connecting these regions were detected and preserved during the resection. Postoperatively, the patient presented a slight dysarthria, then recovered. This is the first report of direct tracking of the subcortical connectivity underlying the fronto-parietal articulatory loop, allowing to better understand the pathophysiology of this network and the consequences of its damage.

Adult↗

Peyer's patch organogenesis is intact yet formation of B lymphocyte follicles is defective in peripheral lymphoid organs of mice deficient for tumor necrosis factor and its 55-kDa receptor.

Targeted inactivation of genes in the tumor necrosis factor (TNF)/lymphotoxin (LT) ligand and receptor system has recently revealed essential roles for these molecules in lymphoid tissue development and organization. Lymphotoxin-alphabeta (LTalphabeta)/lymphotoxin-beta receptor (LTbeta-R) signaling is critical for the organogenesis of lymph nodes and Peyer's patches and for the structural compartmentalization of the splenic white pulp into distinct B and T cell areas and marginal zones. Moreover, an essential role has been demonstrated for TNF/p55 tumor necrosis factor receptor (p55TNF-R) signaling in the formation of splenic B lymphocyte follicles, follicular dendritic cell networks, and germinal centers. In contrast to a previously described essential role for the p55TNF-R in Peyer's patch organogenesis, we show in this report that Peyer's patches are present in both TNF and p55TNF-R knockout mice, demonstrating that these molecules are not essential for the organogenesis of this lymphoid organ. Furthermore, we show that in the absence of TNF/p55TNF-R signaling, lymphocytes segregate normally into T and B cell areas and a normal content and localization of dendritic cells is observed in both lymph nodes and Peyer's patches. However, although B cells are found to home normally within Peyer's patches and in the outer cortex area of lymph nodes, organized follicular structures and follicular dendritic cell networks fail to form. These results show that in contrast to LTalphabeta signaling, TNF signaling through the p55TNF-R is not essential for lymphoid organogenesis but rather for interactions that determine the cellular and structural organization of B cell follicles in all secondary lymphoid tissues.

Animals↗

Peyer's patch organogenesis--cytokines rule, OK?

Targeted inactivation of genes in the tumor necrosis factor (TNF)/lymphotoxin (LT) ligand and receptor system has recently revealed essential roles forthese molecules in lymphoid tissue development and organization. Lymphotoxin-alpha beta (LT alpha beta)/lymphotoxin-beta receptor (LT beta-R) signaling is critical for the organogenesis of lymph nodes and Peyer's patches and for the structural compartmentalization of the splenic white pulp into distinct B and T cell areas and marginal zones. Moreover, an essential role has been demonstrated for TNF/p55 tumor necrosis factor receptor (p55TNF-R) signaling in the formation of splenic B lymphocyte follicles, follicular dendritic cell networks, and germinal centers. In contrast to a previously described essential role for the p55TNF-R in Peyer's patch organogenesis, we show in this report that Peyer's patches are present in both TNF and p55TNF-R knockout mice, demonstrating that these molecules are not essential for the organogenesis of this lymphoid organ. Furthermore, we show that in the absence of TNF/p55TNF-R signaling, lymphocytes segregate normally into T and B cell areas and a normal content and localization of dendritic cells is observed in both lymph nodes and Peyer's patches. However, although B cells are found to home normally within Peyer's patches and in the outer cortex area of lymph nodes, organized follicular structures and follicular dendritic cell networks fail to form. These results show that in contrast to LT alpha beta signaling, TNF signaling through the p55TNF-R is not essential for lymphoid organogenesis but rather for interactions that determine the cellular and structural organization of B cell follicles in all secondary lymphoid tissues.

Animals↗

Advances in participatory occupational health aimed at good practices in small enterprises and the informal sector.

Participatory programmes for occupational risk reduction are gaining importance particularly in small workplaces in both industrially developing and developed countries. To discuss the types of effective support, participatory steps commonly seen in our "work improvement-Asia" network are reviewed. The review covered training programmes for small enterprises, farmers, home workers and trade union members. Participatory steps commonly focusing on low-cost good practices locally achieved have led to concrete improvements in multiple technical areas including materials handling, workstation ergonomics, physical environment and work organization. These steps take advantage of positive features of small workplaces in two distinct ways. First, local key persons are ready to accept local good practices conveyed through personal, informal approaches. Second, workers and farmers are capable of understanding technical problems affecting routine work and taking flexible actions leading to solving them. This process is facilitated by the use of locally adjusted training tools such as local good examples, action checklists and group work methods. It is suggested that participatory occupational health programmes can work in small workplaces when they utilize low-cost good practices in a flexible manner. Networking of these positive experiences is essential.

Accident Prevention↗