Research in the application of artificial intelligence to lung cancer diagnosis

The morbidity and mortality rates in lung cancer are high worldwide. Early diagnosis and personalized treatment are important to manage this public health issue. In recent years, artificial intelligence (AI) has played increasingly important roles in early screening, auxiliary diagnosis, and prognostic assessment. AI uses algorithms to extract quantitative feature information from high-volume and high-latitude data and learn existing data to predict disease outcomes. In this review, we describe the current uses of AI in lung cancer-focused pathomics, imageomics, and genomics applications.

Rotenone and elevated extracellular potassium concentration induce cell-specific fibrillation of α-synuclein in axons of cholinergic enteric neurons in the guinea-pig ileum

BACKGROUND

Parkinson's disease is a progressive neurodegenerative disorder that results in the widespread loss of select classes of neurons throughout the nervous system. The pathological hallmarks of Parkinson's disease are Lewy bodies and neurites, of which α-synuclein fibrils are the major component. α-Synuclein aggregation has been reported in the gut of Parkinson's disease patients, even up to a decade before motor symptoms, and similar observations have been made in animal models of disease. However, unlike the central nervous system, the nature of α-synuclein species that form these aggregates and the classes of neurons affected in the gut are unclear. We have previously reported selective expression of α-synuclein in cholinergic neurons in the gut (J Comp Neurol. 2013; 521:657), suggesting they may be particularly vulnerable to degeneration in Parkinson's disease.

METHODS

In this study, we used immunohistochemistry to detect α-synuclein oligomers and fibrils via conformation-specific antibodies after rotenone treatment or prolonged exposure to high [K⁺ ] in ex vivo segments of guinea-pig ileum maintained in organotypic culture.

KEY RESULTS

Rotenone and prolonged raising of [K⁺ ] caused accumulation of α-synuclein fibrils in the axons of cholinergic enteric neurons. This took place in a time- and, in the case of rotenone, concentration-dependent manner. Rotenone also caused selective necrosis, indicated by increased cellular autofluorescence, of cholinergic enteric neurons, labeled by ChAT-immunoreactivity, also in a concentration-dependent manner.

CONCLUSIONS & INFERENCES

To our knowledge, this is the first report of rotenone causing selective loss of a neurochemical class in the enteric nervous system. Cholinergic enteric neurons may be particularly susceptible to Lewy pathology and degeneration in Parkinson's disease.

Sensory innervation of the guinea pig colon and rectum compared using retrograde tracing and immunohistochemistry

BACKGROUND

Neurons in lumbar and sacral dorsal root ganglia (DRG) comprise extrinsic sensory pathways to the distal colon and rectum, but their relative contributions are unclear. In this study, sensory innervation of the rectum and distal colon in the guinea pig was directly compared using retrograde labeling combined with immunohistochemistry.

METHODS

The lipophilic tracer, DiI, was injected in either the rectum or distal colon of anesthetized guinea pigs, then DRG (T6 to S5) and nodose ganglia were harvested and labeled using antisera for calcitonin gene-related peptide (CGRP) and transient receptor potential vanilloid 1(TRPV1).

KEY RESULTS

More primary afferent cell bodies were labeled from the rectum than from the distal colon. Vagal sensory neurons, with cell bodies in the nodose ganglia comprised fewer than 0.5% of labeled sensory neurons. Spinal afferents to the distal colon were nearly all located in thoracolumbar DRG, in a skewed unimodal distribution (peak at L2); fewer than 1% were located in sacral ganglia. In contrast, spinal afferents retrogradely labeled from the rectum had a bimodal distribution, with one peak at L3 and another at S2. Fewer than half of all retrogradely labeled spinal afferent neurons were immunoreactive for CGRP or TRPV1 and these included the larger traced neurons, especially in thoracolumbar ganglia.

CONCLUSIONS & INFERENCES

In the guinea pig, both the distal colon and the rectum receive a sensory innervation from thoracolumbar ganglia. Sacral afferents innervate the rectum but not the distal colon. Calcitonin gene-related peptide immunoreactivity was detectable in fewer than half of afferent neurons in both pathways.

MicroRNA-141 inhibits vascular smooth muscle cell proliferation through targeting PAPP-A

It is well known that ox-LDL plays key roles in the development of atherosclerosis, partly by inducing vascular smooth muscle cells (VSMCs) proliferation. Recent findings have revealed that microRNAs, a class of small noncoding RNAs, could regulate cell proliferation in many physiological and pathological conditions. However, the role and function of miRNAs on ox-LDL induced VSMC proliferation are not fully elucidated. In this study, we showed that ox-LDL could suppress miR-141 expression and inhibition of miR-141 could promote VSMCs proliferation. Moreover, we found that PAPPA was the direct target gene of miR-141. Overexpression of PAPPA impaired the miR-141-induced inhibition of proliferation in the VSMCs. Taken together; miR-141 may play important roles in ox-LDL-induced abnormal proliferation of the VSMC.

Activation of intestinal spinal afferent endings by changes in intra-mesenteric arterial pressure

KEY POINTS

A major class of mechano-nociceptors to the intestine have mechanotransduction sites on extramural and intramural arteries and arterioles ('vascular afferents'). These sensory neurons can be activated by compression or axial stretch of vessels. Using isolated preparations we showed that increasing intra-arterial pressure, within the physiological range, activated mechano-nociceptors on vessels in intact mesenteric arcades, but not in isolated arteries. This suggests that distortion of the branching vascular tree is the mechanical adequate stimulus for these sensory neurons, rather than simple distension. The same rises in pressure also activated intestinal peristalsis in a partially capsaicin-sensitive manner indicating that pressure-sensitive vascular afferents influence enteric circuits. The results identify the mechanical adequate stimulus for a major class of mechano-nociceptors with endings on blood vessels supplying the gut wall; these afferents have similar endings to ones supplying other viscera, striated muscle and dural vessels.

ABSTRACT

Spinal sensory neurons innervate many large blood vessels throughout the body. Their activation causes the hallmarks of neurogenic inflammation: vasodilatation through the release of the neuropeptide calcitonin gene-related peptide and plasma extravasation via tachykinins. The same vasodilator afferent neurons show mechanical sensitivity, responding to crushing, compression or axial stretch of blood vessels - responses which activate pain pathways and which can be modified by cell damage and inflammation. In the present study, we tested whether spinal afferent axons ending on branching mesenteric arteries ('vascular afferents') are sensitive to increased intravascular pressure. From a holding pressure of 5 mmHg, distension to 20, 40, 60 or 80 mmHg caused graded, slowly adapting increases in firing of vascular afferents. Many of the same afferent units showed responses to axial stretch, which summed with responses evoked by raised pressure. Many vascular afferents were also sensitive to raised temperature, capsaicin and/or local compression with von Frey hairs. However, responses to raised pressure in single, isolated vessels were negligible, suggesting that the adequate stimulus is distortion of the arterial arcade rather than distension per se. Increasing arterial pressure often triggered peristaltic contractions in the neighbouring segment of intestine, an effect that was mimicked by acute exposure to capsaicin (1 μm) and which was reduced after desensitisation to capsaicin. These results indicate that sensory fibres with perivascular endings are sensitive to pressure-induced distortion of branched arteries, in addition to compression and axial stretch, and that they contribute functional inputs to enteric motor circuits.

Surgical femorocaval bypass for treating chronic iliac vein occlusion: a case report

Chronic inferior vena cava and iliac vein occlusion, caused by long-term of deep venous thrombosis, will lead to swelling of the limbs, venous claudication and intractable ulcer. However, conservative treatment is often ineffective for vein occlusion. With the development of interventional techniques, endovascular therapy has become the first choice for the treatment of vein occlusion with higher success rate and lower trauma. However, for cases those fail endovascular therapy or for segmental veno-occlusive diseases with low long-term patency rate, venous bypass might be the only option. And, design of anastomotic stoma and orificium fistulae design is crucial to the success of operation. A case of long term deep venous thrombosis patient with occlusion in bilateral iliac vein and distal inferior vena cava was admitted and treated with interventional therapy. Unfortunately, this method failed. Then, we selected reasonable anastomotic stoma and orificium fistulae and performed femorocaval bypass. The 12 month follow-up results showed that the swelling was successively relieved and the ulcer healed. This indicated that rational anastomotic stoma and orificium fistulae could guarantee the exact clinical efficacy of venous bypass and higher long-term patency rate.

[Characteristic changes of vascular tension factors in diabetic arterial occlusion of lower extremities]

OBJECTIVE

To study the change of vascular tension factors (VTF), including vascular contractile factors as endothelin-1 (ET-1), thromboxane A2 (TXA2) and vascular dilatory factors as nitric oxide (NO), prostacyclin (PGI2), in different stage of peripheral diabetic arterial occlusion (PDAO), and to preliminarily explore the clinical significance of these changes.

METHODS

VTF in 40 diabetic patients, 15 of 2nd stage and 25 of 3rd stage, were observed by measuring level of ET-1, NO, TXB2 and 6-keto-PGF1alpha in blood plasma with RIA assay.

RESULTS

(1) ET-1 and TXB2 levels in all patients were higher than those in control (P < 0.05 and P < 0.01), those in patients of 3rd stage was higher than those of 2nd stage, showing significant difference (P < 0.05). (2) NO and 6-keto-PGF1alpha levels in all patients was lower than those in control, but showed no significant difference between patients of various stages (P > 0.05).

CONCLUSION

There are changes of VTF in patients with PDAO, manifesting as increase of vascular contractive factors and decrease of vascular dilative factor. The changes are diffrent in various stages, the vascular contractive and thrombotic factors in patients of 3rd stage are higher than those in patients of 2nd stage, but the injury on vascular dilative factors in the two stages showed insignificant difference.

Intraganglionic laminar endings are mechano-transduction sites of vagal tension receptors in the guinea-pig stomach

1. Distension-sensitive vagal afferent fibres from the cardiac region of the guinea-pig stomach were recorded extracellularly, then filled with biotinamide, using an anterograde tracing technique. 2. Most of the stretch-sensitive units of the guinea-pig stomach (41 out of 47; number of animals N = 26) had low thresholds (less than 1 mm) to circumferential stretch and showed slow adaptation. Twenty of these units fired spontaneously under resting conditions (mean: 1.9 +/- 0.3 Hz, n = 20, N = 14). 3. Adaptation of firing during slow or maintained stretch correlated closely with accommodation of intramural tension, but tension-independent adaptation was also present. 4. Nicardipine (3 microM) with hyoscine (3 microM) reduced stretch-evoked firing of gastric vagal afferents, by inhibiting smooth muscle contraction. Gadolinium (1 mM) blocked distension-evoked firing. 5. Focal stimulation of the stomach muscle wall with a von Frey hair (0.4 mN) identified one to six punctate receptive fields in each low threshold vagal distension-sensitive afferent. These were marked on the serosal surface of the stomach wall. 6. Anterograde filling of recorded nerve trunks revealed intraganglionic laminar endings (IGLEs) within 142 +/- 34 microm (n = 38; N = 10) of marked receptive fields. The mean distance from randomly generated sites to the nearest IGLE was significantly greater (1500 +/- 48 microm, n = 380, N = 10, P < 0.0001). Viscerofugal nerve cell bodies, intramuscular arrays and varicose axons were not associated with receptive fields. The results indicate that IGLEs are the mechanotransduction sites of low threshold, slowly adapting vagal tension receptors in the guinea-pig upper stomach.

Quantitative analysis of peristalsis in the guinea-pig small intestine using spatio-temporal maps

1. Peristalsis was evoked in guinea-pig small intestine by slow fluid infusion and recorded onto video and digitized. Spatio-temporal maps of diameter and longitudinal movement were constructed and parameters of motion were calculated. 2. During the filling of the isolated segments of intestine, rhythmic local longitudinal movements were observed at several points along the preparation. These phasic longitudinal muscle contractions were associated with small but significant local increases in diameter and probably reflect a passive mechanical coupling by connective tissue in the gut wall. In addition, occasional synchronized longitudinal muscle contractions caused net shortening of the preparation and always preceded the onset of peristaltic emptying. 3. Peristaltic emptying was characterized by a contraction of the circular muscle which usually started at the oral end of the preparation, that propagated aborally, propelling the contents. However, in 19 % of trials, the first circular muscle contraction occurred in the aboral half of the preparation. 4. The propagation of peristalsis consisted of separate sequential circular muscle contractions several centimetres long, particularly in the oral half of the preparation, giving a 'step-like' appearance to the spatio-temporal map. The gut was transiently distended aboral to the propagating circular muscle contraction due to the propulsion of contents. 5. At each point in the preparation, the longitudinal muscle remained contracted during the propulsive part of the circular muscle contraction. Only when the circular muscle contraction became lumen occlusive did lengthening of the longitudinal muscle take place. 6. Spatio-temporal maps are a powerful tool to visualize and analyse the complexity of gastrointestinal motility patterns.

Initiation of peristalsis by circumferential stretch of flat sheets of guinea-pig ileum

1. Segments of isolated guinea-pig intestine, 12 mm long, were distended slowly by intraluminal fluid infusion or by mechanical stretch as either a tube or flat sheet. In all cases, at a constant threshold length, a sudden, large amplitude contraction of the circular muscle occurred orally, corresponding to the initiation of peristalsis. 2. Circumferential stretch of flat sheet preparations evoked graded contractions of the longitudinal muscle (the 'preparatory phase'), which were maintained during circular muscle contraction. This suggests that the lengthening reported during the emptying phase of peristalsis is due to mechanical interactions. 3. The threshold for peristalsis was lower with more rapid stretches and was also lower in long preparations (25 mm) compared with short preparations (5-10 mm), indicating that ascending excitatory pathways play a significant role in triggering peristalsis. 4. Stretching a preparation beyond the threshold for peristalsis evoked contractions of increasing amplitude; thus peristalsis is graded above its threshold. However, during suprathreshold stretch maintained at a constant length, contractions of the circular muscle quickly declined in amplitude and frequency. 5. Circular muscle cells had a resting membrane potential approximately 6 mV more negative than the threshold for action potentials. During slow circumferential stretch, subthreshold graded excitatory motor input to the circular muscle occurred, prior to the initiation of peristalsis. However, peristalsis was initiated by a discrete large excitatory junction potential (12 +/- 2 mV) which evoked bursts of smooth muscle action potentials and which probably arose from synchronized firing of ascending excitatory neuronal pathways.

[Clinical study on treatment of arteriosclerosis obliterans using huangqi tongmai decoction]

OBJECTIVE

To test and verify the effects of Huangqi Tongmai Decoction (HQTMI) regulating blood lipid in treating arteriosclerosis obliterans (ASO).

METHODS

Thirty-two cases of ASO was treated with HQTMD for two months. The drug was in water decoction, oral taken.

RESULTS

Compared with the blood lipid level before treatment, the high density lipoprotein of cholesterol (HDL-C) was increased, the low density lipoprotein of cholesterol (LDL-C), atherogenic index (AI) was decreased (P < 0.01). The serum total cholesterol (TC), triglyceride (TG), very low density lipoprotein of cholesterol (VLDL), apolipoprotein A1 (apoA1), apolipoprotein B100 (apoB100) were all changed (P < 0.05). apoA1/apoB100 ratio increased.

CONCLUSION

HQTMD could regulate blood lipid. This method was effective in treating ASO.

Characterization of excitatory and inhibitory motor neurons to the guinea pig lower esophageal sphincter

BACKGROUND & AIMS

The lower esophageal sphincter is innervated primarily by enteric motor neurons. The somata of excitatory and inhibitory motor neurons were identified and mapped.

METHODS

Retrograde labeling in organotypic culture and immunohistochemistry were used to identify motor neuron somata.

RESULTS

1,1'-Didodecyl-3,3,3',3'-tetramethyl indocarbocyanine perchlorate (Dil) on the left side of the sphincter labeled descending motor neurons located up to 26 mm along the esophagus and locally (within 2 mm) and gastric motor neurons. Dil applied to the right side of the sphincter labeled descending and local motor neurons but very few gastric motor neurons. Inhibitory motor neuron cell bodies, identified by nitric oxide synthase immunoreactivity, accounted for 86% +/- 4% (n = 6) of descending motor neurons and 53% +/- 4% of local motor neurons labeled from the right side. Excitatory motor neurons, immunoreactive for choline acetyltransferase, accounted for 20% +/- 3% (n = 6) of descending motor neurons and for 47% +/- 4% of local motor neurons. All motor neurons were unipolar, but inhibitory motor neurons were significantly larger than excitatory neurons.

CONCLUSIONS

The lower esophageal sphincter is innervated by local excitatory and inhibitory motor neurons and by descending esophageal inhibitory neurons. The oblique muscle, supplied by gastric motor neurons, is closely associated with the gastroesophageal junction.

Effect of ischaemia and role of eicosanoids in release of atrial natriuretic factor from rat heart

OBJECTIVE

The aim was to investigate (1) the relationship between atrial natriuretic factor (ANF) release and the extent of ischaemia-hypoxia, and (2) the potential role of eicosanoids in ANF release during global ischaemia, particularly the cyclo-oxygenase derivatives (prostaglandins) and the lipoxygenase derivatives (leukotrienes).

METHODS

Using an isolated perfused, spontaneously beating rat heart, global ischaemia was achieved by the reduction of perfusion flow rate relative to basal flow rate. ANF was measured by radioimmunoassay.

RESULTS

A decrease in perfusion flow rate by 75-80% to a final value of 2-2.5 ml.min-1.g-1 heart (n = 6) caused a gradual but sustained increase of ANF release which reached a plateau after 12 min, attaining a peak value of 89.9 (SEM 26.6)% over baseline. A decrease in perfusion flow rate by 55-60% (n = 5) also resulted in an increased ANF secretion, with a peak of 125.6(23.2)% over baseline at 14 min. A decrease in perfusion flow rate by 25-30% to a final value of 5-6.75 ml.min-1.g-1 heart (n = 4) showed no change in ANF release. The mean basal value of ANF release was 8.23(2.39) ng.min-1.g-1 heart (n = 26). In a separate series of experiments using a reduction of 55-60% in perfusion flow rate but with the addition to the perfusion medium of the specific cyclo-oxygenase inhibitor meclofenamate 10 microM (n = 5) or the lipoxygenase inhibitor nordihydroguaiaretic acid 10 microM (n = 5), no increase in ANF release occurred during the period of global ischaemia. Neither inhibitor affected ANF release during basal perfusion rates (7-9 ml.min-1.g-1 heart).

CONCLUSIONS

ANF released in response to global ischaemia is likely to be mediated by prostanoids generated via the cyclo-oxygenase pathway and leukotrienes generated via the lipoxygenase pathway. Both pathways may provide important paracrine/autacoid regulatory roles for the protection of the heart during ischaemia by stimulating ANF release, with the subsequent beneficial effects of the peptide on peripheral tissues, ultimately leading to a reduction in load on the heart.

Prostaglandin F2 alpha mediates platelet-activating factor-stimulated atrial natriuretic factor release from the isolated rat heart

Platelet-activating factor (PAF) and the prostaglandins have recently been shown to stimulate atrial natriuretic factor (ANF) secretion from the heart. As PAF also potentiates the release of cyclooxygenase products from isolated hearts, the role of these substances in PAF-induced ANF secretion was investigated. Using an isolated perfused rat heart preparation, cyclooxygenase inhibition by indomethacin or meclofenamic acid (10 microM for each) significantly attenuated the rise in ANF associated with PAF administration (2.5 nmol). Prostaglandin F2 alpha (PGF) produced an immediate and dose-dependent increase in ANF secretion, which was significant at 0.01 mumol and reached 348 +/- 66% over baseline values after a 1-mumol injection. Prostaglandin E2 (PGE) generated a much smaller 98 +/- 25% increase after a 1-mumol administration. Furthermore, PGF but not PGE was released from isolated hearts immediately after PAF administration. PGF release reached a maximum of 0.06 nmol/min g Heart-1 1 min after PAF stimulation and had returned to undetectable baseline values by 6 min. Cyclooxygenase inhibition abolished the release of PGF after PAF, in addition to attenuating (by 60-70%) the increased secretion of ANF after PAF injection. These results demonstrate very clearly that PGF is the major mediator for PAF-stimulated ANF secretion. Such an interaction may provide an alternative mechanism to atrial distension for the secretion of ANF in pathologies such as myocardial infarction, where autacoids such as PAF and the PGs are released from damaged cardiac muscle and elevated plasma levels of ANF are observed.