Current status and prospects of basic research and clinical application of mesenchymal stem cells in acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a common and clinically devastating disease that causes respiratory failure. Morbidity and mortality of patients in intensive care units are stubbornly high, and various complications severely affect the quality of life of survivors. The pathophysiology of ARDS includes increased alveolar-capillary membrane permeability, an influx of protein-rich pulmonary edema fluid, and surfactant dysfunction leading to severe hypoxemia. At present, the main treatment for ARDS is mechanical treatment combined with diuretics to reduce pulmonary edema, which primarily improves symptoms, but the prognosis of patients with ARDS is still very poor. Mesenchymal stem cells (MSCs) are stromal cells that possess the capacity to self-renew and also exhibit multilineage differentiation. MSCs can be isolated from a variety of tissues, such as the umbilical cord, endometrial polyps, menstrual blood, bone marrow, and adipose tissues. Studies have confirmed the critical healing and immunomodulatory properties of MSCs in the treatment of a variety of diseases. Recently, the potential of stem cells in treating ARDS has been explored via basic research and clinical trials. The efficacy of MSCs has been shown in a variety of in vivo models of ARDS, reducing bacterial pneumonia and ischemia-reperfusion injury while promoting the repair of ventilator-induced lung injury. This article reviews the current basic research findings and clinical applications of MSCs in the treatment of ARDS in order to emphasize the clinical prospects of MSCs.

Application of laser capture microdissection and PCR sequencing in the diagnosis of Coccidioides spp. infection: A case report and literature review in China

Coccidioidomycosis is endemic to California, Arizona, and Mexico. In recent years, the reported cases of coccidioidomycosis have increased in nonendemic regions. Here, we reported a case of imported pulmonary coccidioidomycosis in a Chinese patient. A 63-year-old man presented with dry cough and fatigue for 6 months, and a computed tomography scan revealed a solitary nodule in the right lower lung and small nodules in both lungs. The diagnosis of coccidioidomycosis was initially confirmed by histopathologic examination. The pathogen Coccidioides spp. was identified by laser capture microdissection (LCM) combined with subsequent molecular techniques based on the positive histopathologic features. Additionally, we reviewed 47 reported cases of coccidioidomycosis in China. The number of reported cases is increasing, and the incidence of disseminated infection has exhibited a trend of shifting towards healthy young adults in China. Since clinical presentations and imaging findings lack specificity, a majority of domestic cases of coccidioidomycosis were initially misdiagnosed as tumours or tuberculosis. Moreover, the diagnosis of endemic mycoses may be challenging because of their rarity and the limited availability of diagnostic tests. The diagnosis was mainly confirmed by histopathological examination. The species involved were identified based on positive cultures in only 4 cases. To our knowledge, this is the first study to use LCM and molecular techniques to identify Coccidioides spp. in the histopathologically positive but uncultivable specimen. Comparing with previous reported studies, LCM combined with nucleic acid amplification techniques improve the ability of species identification for the timely diagnosis of coccidioidomycosis.

The role of nitric oxide in peptic ulcer: a narrative review

Peptic ulcer refers to the inflammatory response and necrotic lesions of the mucosa under the action of various pathogenic factors, which goes deeply into the mucosal muscle layer and often occurs to the gastrointestinal mucosa related to gastric acid secretion, among which the stomach and duodenum are the most common. The clinical manifestations include slow onset, prolonged course and weekly upper abdominal pain. Nitric oxide (NO) is an intracellular and intercellular signaling molecule that plays an important role in many physiological and pathological processes. Studies have found that a small amount of NO produced in vivo plays a role in many physiological homeostasis, such as regulating blood pressure, platelet aggregation, nitrogenization of hemoglobin, and regulating proliferation and differentiation of stem cells. However, under the action of some cytokines and oxidative stress, intracellular NO synthase will catalyze the synthesis of large amounts of NO and participate in the inflammatory response, causing beneficial or harmful effect on the body. Numerous basic studies have focused on the relationship between NO and peptic ulcer. The purpose of this review is to summarize the role of NO in peptic ulcer and its possible mechanism.

The role of hyperbaric oxygen therapy in inflammatory bowel disease: a narrative review

Inflammatory bowel disease is a group of chronic recurrent diseases in the digestive tract, including ulcerative colitis and Crohn's disease. Over the past few decades, the treatment of IBD has made great progress but there is still a lot of room for improvement. Hyperbaric oxygen therapy (HBOT) was defined as the therapeutic effect of inhaling 100% oxygen higher than one atmosphere and reported to be used in stroke, decompression sickness and wound healing. Since several authors reported the role of HBOT as an adjunct to conventional medical treatment in patients with refractory IBD, the relevant research has shown an increasing trend in recent years. Clinical and experimental studies have revealed that HBOT may exert its therapeutic effect by inhibiting inflammation and strengthening the antioxidant system, promoting the differentiation of colonic stem cells and recruiting cells involved in repair. The purpose of this review is to summarize the past clinical and experimental studies and to understand the impact of HBOT in the treatment of IBD more deeply. In addition, we also hope to provide some ideas for future clinical and research work.

Protective effects of sevoflurane in cerebral ischemia reperfusion injury: a narrative review

Ischemia/reperfusion (I/R) injury is a phenomenon that the reperfusion of ischemic organs or tissues aggravates their damage, which poses a serious health threat and economic burden to the world. I/R gives rise to a series of physiological and pathological world, including inflammatory response, oxidative stress, brain edema, blood-brain barrier destruction, and neuronal death. Therefore, finding effective treatment measures is extremely important to the recovery of I/R patients and the improvement of long-term quality of life. Sevoflurane is an important volatile anesthetic which has been reported to reduce myocardial I/R damage and infarct size. Sevoflurane also has anti-inflammatory and neuroprotective effects. As reported sevoflurane treatment could reduce nerve function injury, cerebral infarction volume and the level of inflammatory factors. At the same time, there is evidence that sevoflurane can reduce neuron apoptosis and antioxidant stress. The protective effect of sevoflurane in brain injury has been proved to be existed in several aspects, so that a comprehensive understanding of its neuroprotective effect is helpful to exploit new treatment paths for I/R, provide clinicians with new clinical treatment decisions, contribute to the effective treatment of I/R patients and the improvement of quality of life after I/R healing.

Acyl-CoA synthetase long chain family member 4 plays detrimental role in early brain injury after subarachnoid hemorrhage in rats by inducing ferroptosis

Aims

Acyl‐CoA synthetase long chain family member 4 (ACSL4) is closely related to tumor genesis and development in certain tissues. However, the function of ACSL4 in early brain injury (EBI) caused by subarachnoid hemorrhage (SAH) is unclear. In this study, we investigated the expression patterns and role of ACSL4 in SAH and post‐SAH EBI using a rat model of SAH.

Methods

The rat model of SAH was induced by autologous blood injection into the prechiasmatic cistern of rats. We also used two specific inhibitors of ferroptosis (Ferrostatin‐1 and Liproxstatin‐1) to investigate the role of ferroptosis in EBI.

Results

We found that ACSL4 levels in brain tissue increased significantly in post‐SAH EBI. Inhibiting the expression of ACSL4 using small interfering RNAs alleviated inflammation, blood‐brain barrier (BBB) impairment, oxidative stress, brain edema, and behavioral and cognitive deficits, and increased the number of surviving neurons, after SAH. Similar effects were obtained by suppressing ferroptosis.

Conclusions

ACSL4 exacerbated SAH‐induced EBI by mediating ferroptosis. These findings may provide a theoretical basis for potential therapy aimed at alleviating post‐SAH EBI.

Physical map of the region surrounding the ataxia-telangiectasia gene on human chromosome 11q22-23

Ataxia telangiectasia (A-T) is an autosomal recessive disease affecting multiple systems, including the development of the cerebellum and thymus. This results in a progressive cerebellar ataxia with onset between 1-3 years, telangiectasia occurs within the subsequent 3-5 years. We localized the A-T gene by linkage analysis to chromosome 11q22-23, between the markers D11S384, and D11S535, and constructed a series of contigs using three BACs and twelve cosmids, spanning a region of approximately 400 kb. We developed a set of sequence-tagged site (STS) markers from the ends of the BACs and cosmids. The A-T gene was isolated from within this region. It is now possible to precisely orient specific BACs, cosmids, and STSs with respect to the exons of the A-T gene (ATM). We anticipate that this information will be useful for further studies of functional domains and regulatory elements within the ATM gene, as well as for other genes in this region. In addition, these clones can be used for FISH studies of deletions, translocations and for loss of heterozygosity in various tumors.

Coronary plaque erosion without rupture into a lipid core. A frequent cause of coronary thrombosis in sudden coronary death

BACKGROUND

Coronary thrombosis has been reported to occur most frequently in lipid-rich plaques with rupture of a thin fibrous cap and contact of the thrombus with a pool of extracellular lipid. However, the frequency of coronary artery thrombosis with or without fibrous cap rupture in sudden coronary death is unknown. In this study, we compared the incidence and morphological characteristics of coronary thrombosis associated with plaque rupture versus thrombosis in eroded plaques without rupture.

METHODS AND RESULTS

Fifty consecutive cases of sudden death due to coronary artery thrombosis were studied by histology and immunohistochemistry. Plaque rupture of a fibrous cap with communication of the thrombus with a lipid pool was identified in 28 cases. Thrombi without rupture were present in 22 cases, all of which had superficial erosion of a proteoglycan-rich plaque. The mean age at death was 53 +/- 10 years in plaque rupture cases versus 44 +/- 7 years in eroded plaques without rupture (P < .02). In the plaque-rupture group, 5 of 28 (18%) were women versus 11 of 22 (50%) with eroded plaques (P = .03). The mean percent luminal area stenosis was 78 +/- 12% in plaque rupture and 70 +/- 11% in superficial erosion (P < .03). Plaque calcification was present in 69% of ruptures versus 23% of erosions (P < .002). In plaque ruptures, the fibrous cap was infiltrated by macrophages in 100% and T cells in 75% of cases compared with 50% (P < .0001) and 32% (P < .004), respectively, in superficial erosions. Clusters of smooth muscle cells adjacent to the thrombi were present in 95% of erosions versus 33% of ruptures (P < .0001). HLA-DR expression was more often seen in macrophages and T cells in ruptures (25 of 28 cases) compared with expression in macrophages in superficial erosion arteries (8 of 22 cases, P = .0002).

CONCLUSIONS

Erosion of proteoglycan-rich and smooth muscle cell-rich plaques lacking a superficial lipid core or plaque rupture is a frequent finding in sudden death due to coronary thrombosis, comprising 44% of cases in the present study. These lesions are more often seen in younger individuals and women, have less luminal narrowing and less calcification, and less often have foci of macrophages and T cells compared with plaque ruptures.

Stimulation of precise excision and recombination by conjugal proficient F'plasmids

Large F plasmids such as F'128 stimulate precise excision of the transposons Tn5 and Tn10 in E. coli K12. This stimulation occurs when the transposons are either on the F'128 plasmid or the bacterial chromosome. Stimulation of precise excision is dependent upon conjugal transfer proficient F'plasmids. Tra- mutations which are defective in conjugal transfer negate this F'128 plasmid stimulation effect. F'128 traS mutations, which are surface exclusion defective and thus permit matings between male cells, thereby increasing conjugal transfer, increase the F plasmid stimulation effect. When the F' plasmid is present in a cell with the small plasmid, pRS31, carrying the traS to traZ region of F, stimulation of precise excision is no longer observed. This complementation-like activity by pRS31 is abolished by a Tn5 insertion in the traS gene. Data are presented supporting the notion that F' plasmid stimulation of precise excision occurs in the recipient during conjugal transfer. F'128 traS also stimulates recA-dependent recombination between DNA sequences on the small, nontransferrable plasmid pRDK41, DNA sequences that are unrelated to those of the F plasmid. The F'plasmid stimulation of precise excision of Tn5 is not seen with F+ but only with certain F's with large insertions of chromosomal DNA.

Recombination genes on the Escherichia coli sex factor specific for transposable elements

The Escherichia coli sex factor stimulates precise excision of transposons Tn5 and Tn10 from sites either within the bacterial chromosome or within the factor itself. We have isolated two kinds of mutations that affect this activity. The ferA mutations eliminate the stimulation; the ferB mutations enhance it in the presence of FerA+. We conclude that ferA defines a sex factor gene that stimulates precise excision. The ferB mutations also specifically increase the rate of recombination between two IS3 elements on F' lac-pro (F'128) in a reaction that requires the product of recA. The stimulation of this recombination by ferB also requires an active ferA gene, which implies that the ferA gene stimulates this reaction as well as precise excision. A ferA mutation was mapped at 84.2 kilobases on the F factor, and a ferB mutation was mapped at 82.5 kilobases. The fer mutants were obtained by an approach that permits the isolation of mutants affecting precise excision.