Automatic detection of small bowel lesions with different bleeding risks based on deep learning models

BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some unresolved challenges.AIM To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups.METHODS The proposed model represents a two-stage method that combined image classification with object detection.First,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid images.Then,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was marked.We constructed training and testing sets and compared model-assisted reading with physician reading.RESULTS The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single module.The sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’diagnoses.The image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.

Short-term efficacy and influencing factors of conventional chemotherapy combined with irinotecan in patients with advanced gastric cancer

BACKGROUND Gastric cancer is one of the most common cancers worldwide, with a 5-year survival rate of only 20%. The age of onset of gastric cancer is in line with the general rule of cancer. Most of them occur after middle age, mostly between 40and 60 years old, with an average age of about 50 years old, and only 5% of patients are under 30 years old. The incidence of male is higher than that of female.AIM To investigate the short-term efficacy and influencing factors of chemotherapy combined with irinotecan in patients with advanced gastric cancer.METHODS Eighty patients with advanced gastric cancer who were treated in our hospital from January 2019 to January 2022 were selected. The patients were divided into an observation group(n = 40) and control group(n = 40) by the envelope method.The control group was given preoperative routine chemotherapy. The observation group was treated with irinotecan in addition to the chemotherapy given to the control group. The short-term efficacy of treatment in the two groups, as well as tumor marker levels and quality of life before and after treatment were evaluated.RESULTS The short-term treatment effect in the observation group was better than that in the control group(P < 0.05), and the total effective rate was 57.50%. The age and proportion of tumor node metastasis(TNM) stage IV patients with ineffective chemotherapy in the observation group were(65.12 ± 5.71) years and 52.94%,respectively, which were notably higher than those of patients with effective chemotherapy(P < 0.05), while the Karnofsky Performance Scale score was(67.70± 3.83) points, which was apparently lower than that of patients with effective chemotherapy(P <0.05). After 3 mo of treatment, the SF-36 scale scores of physiological function, energy, emotional function, and mental health in the observation group were 65.12 ± 8.14, 54.76 ± 6.70, 47.58 ± 7.22,and 66.16 ± 8.11 points, respectively, which were considerably higher than those in the control group(P < 0.05). The incidence rates of grade Ⅲ-Ⅳ diarrhea and grade Ⅲ-Ⅳ thrombocytopenia in the observation group were 32.50% and 25.00%, respectively, which were markedly higher than those in the control group(P < 0.05).CONCLUSION Chemotherapy combined with irinotecan in patients with advanced gastric cancer has a good short-term efficacy and can significantly reduce serum tumor markers and improve the quality of life of patients. The efficacy may be affected by the age and TNM stage of the patients, and its long-term efficacy needs further study.

中性粒细胞与淋巴细胞比值对急性胰腺炎并发急性呼吸窘迫综合征的预测价值

目的探讨中性粒细胞与淋巴细胞比值(NLR)在急性胰腺炎(AP)并发急性呼吸窘迫综合征(ARDS)中的预测价值。方法回顾性分析2015 年10 月—2018 年2 月山西省人民医院收治符合入组标准的93 例确诊为急性胰腺炎(AP)患者的临床资料。根据2012 年ARDS 柏林标准,按是否发生ARDS 分为ARDS阳性组和ARDS 阴性组,观察两组患者临床指标、生化指标及NLR。采用受试者操作特征(ROC)曲线和Logistic 回归分析评估NLR、白细胞计数(WBC)对AP 并发ARDS 的预测价值。结果 93 例符合标准的患者,其中ARDS 阳性组18 例,ARDS 阴性组75 例。两组患者WBC、中性粒细胞计数(ANC)、淋巴细胞计数(ALC)、NLR、淋巴细胞与单核细胞比值(LMR)及心率的比较,差异有统计学意义(P <0.05)。ROC 曲线下最佳临界值为:NLR 15.43、WBC 17.05×10^9/L,ROC 曲线下面积分别为NLR 0.948、WBC 0.869,联合检测为0.955。NLR 和WBC 串联检测时预测AP 发生ARDS 的特异性最高,为100%;NLR 和WBC 并联检测时预测AP 发生ARDS 的敏感性最高为是88.9%(误诊率11.1%)。结论 NLR、WBC 与AP 并发ARDS 密切相关,且两者联合检测对早期预测AP 并发ARDS 的特异性和敏感性最高。

Faecal and mucosal microbiota in patients with functional gastrointestinal disorders: Correlation with toll-like receptor 2/toll-like receptor 4 expression

AIM To investigate the intestinal luminal microbiota(LM)and mucosa-associated microbiota(MAM)in Chinese patients with functional gastrointestinal disorders(FGIDs)and examine the association between these communities and the expression of toll-like receptor(TLR)2 and TLR4. METHODS Thirty-two Chinese subjects who suffered from symptoms of FGIDs,as confirmed by gastroenterologists,were enrolled in this study.Fresh faecal samples and descending colonic mucosal biopsies were collected from the subjects before(faecal)and during(mucosal) flexible colonoscopy.For analysis of the samples,we performed high-throughput sequencing of the V3-V4region of the 16S rR NA gene and reverse transcription(RT)-PCR to detect the expression of colonic TLR2 and TLR4.Differences in the stool and mucosal microbiota were examined and a correlation network analysis was performed. RESULTS The microbiota of faecal samples was significantly more diverse and richer than that of the mucosal samples,and the LM and MAM populations differed significantly.TLR2 expression showed a significant positive correlation with TLR4 expression.In the MAM samples,the genera Faecalibacterium and Ruminococcus,which belong to the family Ruminococcaceae,were inversely correlated with TLR4 expression(r=-0.45817,P=0.0083 and r=-0.5306,P=0.0018,respectively).Granulicatella,which belongs to Carnobacteriaceae,and Streptococcus,which belongs to Streptococcaceae,were inversely correlated with TLR2 expression(r=-0.5573,P=0.0010 and r=-0.5435,P=0.0013,respectively).In the LM samples,examination at phylum,class,or order level revealed no correlation with TLR4 expression.Faecalibacterium,which belongs to Ruminococcaceae,and Streptococcus,which belongs to Streptococcaceae,were inversely correlated with TLR2 expression(r=-0.5743,P=0.0058 and r=-0.3905,P=0.0271,respectively). CONCLUSION Microbial compositions of LM and MAM in Chinese patients with FGIDs are different.Expression of TLRs may be affected by the type of bacteria that are present in the gut.

Analysis of circulating regulatory T cells （CD4 ＋CD25 ＋CD 127-）after cryosurgery in prostate cancer

This study was performed to assess the response of regulatory T cells （Tregs） following cryosurgery in prostate cancer （PCa） patients by measuring their frequency and immune function. Blood was collected prior to and at 4 and 8 weeks after treatment in 30 patients with high-risk PCa who underwent cryosurgery and from 15 healthy volunteers. Circulating CD4＋CD25＋CD127- Tregs were isolated. Their frequency was detected by flow cytometry, and immune suppressive function was evaluated by measuring the proliferation of CD4＋CD25- T cells cocultured with Tregs. The results showed that the percentage of circulating CD4＋CD25＋CD127- Tregs was increased in PCa patients compared to healthy volunteers （7.6%±0.73% vs. 5.8%±0.54%, P〈0.001）. The frequency of circulating CD4＋CD25＋CD127- Tregs was reduced 4 weeks after cryosurgery compared to before surgery （6.3%__.0.58% vs. 7.6%±0.73%, P〈0.001）, and the decrease persisted for 8 weeks. However, the suppressive function of Tregs was increased in eight of 12 patients, which might contribute to cancer recurrence. Then the response of circulating Tregs is complicated after cryosurgery for PCa, and further studies are warranted.

Ubiquitin-conjugating enzyme E2T knockdown suppresses hepatocellular tumorigenesis via inducing cell cycle arrest and apoptosis

BACKGROUND Hepatocellular carcinoma(HCC)is now the most common primary liver malignancy worldwide,and multiple risk factors attribute to the occurrence and development of HCC.Recently,increasing studies suggest that ubiquitinconjugating enzyme E2T(UBE2T)serves as a promising prognostic factor in human cancers,although the molecular mechanism of UBE2T in HCC remains unclear.AIM To investigate the clinical relevance and role of UBE2T in HCC development.METHODS UBE2T expression in HCC tissues from the TCGA database and its association with patient survival were analyzed.A lentivirus-mediated strategy was used to knock down UBE2T in HCC cells.qRT-PCR and Western blot assays were performed to check the effect of UBE2T silencing in HCC cells.Cell growth in vitro and in vivo was analyzed by multiparametric high-content screening and the xenograft tumorigenicity assay,respectively.Cell cycle distribution and apoptosis were determined by flow cytometry.The genes regulated by UBE2T were profiled by microarray assay.RESULTS UBE2T was overexpressed in HCC tissues compared with paired and non-paired normal tissues.High expression of UBE2T predicted a poor overall survival in HCC patients.In vitro,lentivirus-mediated UBE2T knockdown significantly reduced the viability of both SMMC-7721 and BEL-7404 cells.In vivo,the xenograft tumorigenesis of SMMC-7721 cells was largely attenuated by UBE2T silencing.The cell cycle was arrested at G1/S phase in SMMC-7721 and BEL-7404 cells with UBE2T knockdown.Furthermore,apoptosis was increased by UBE2T knockdown.At the molecular level,numerous genes were dysregulated after UBE2T silencing,including IL-1B,FOSL1,PTGS2,and BMP6.CONCLUSION UBE2T plays an important role in cell cycle progression,apoptosis,and HCC development.

Phosphorus removal by adsorbent based on poly-aluminum chloride sludge

Phosphorus adsorption tests were carried out using poly-aluminum chloride sludge(PACS),which was collected from a water treatment plant in Nanjing.The amount of phosphorus adsorbed by PACS increased quickly within the first hour and reached equilibrium after about 48 h.The adsorption behavior of PACS for phosphorus is consistent with the Langmuir adsorption isotherm equation(R2>0.99)and parallel first-order kinetic equation(R2>0.98).With the increase of the PACS concentration,the adsorption capacity of PACS for phosphorus decreased,and the removal rate increased.The results of batch tests showed that the adsorption capacities of PACS for phosphorus ranged from 1.64 to 1.13 mg/g when the pH value varied from 4 to 10.However,the adsorption capacity of PACS was not evidently influenced by temperature.In comparison with the ion exchange resin,the adsorption capacity of PACS was barely inhibited by competitive ions,such as SO2
4,NO
3,and Cl
.The PACS surface after adsorption became smooth,and the vibration peaks of AleO and AleOH shifted.Both HCl and NaOH have a strong desorption effect on PACS after adsorption saturation,and with higher concentrations of HCl and NaOH,the desorption effect was stronger.Results of column adsorption experiments showed that with lower phosphorus and hydraulic loads,the adsorption column took longer to reach saturation.This indicated that PACS could be used as an efficient material for removal of phosphorus from water.This study provides a new treatment method with PACS.

远志汤有效成分对APP/PS1小鼠氧化损伤的保护作用机制研究

目的通过观察远志汤有效成分即β-细辛醚+远志皂苷(TEN)对APP/PS1双转基因小鼠磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)/糖原合成激酶3β(GSK-3β)信号通路的调控,探讨远志汤防治阿尔茨海默病(AD)的作用机制。方法将3月龄APP/PS1双转基因小鼠分为模型组、盐酸多奈哌齐组(0.33 mg/kg·d)、β-细辛醚+TEN低、中和高剂量组[18.5、37.0和74.0 mg/(kg·d)],选同月龄C57BL/6小鼠为空白对照组,采用Morris水迷宫法和新物体识别实验检测小鼠的学习记忆能力,采用分光光度法检测超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)活性,以及丙二醛(MDA)含量。采用Western blot检测GSK-3β、Akt,以及两者磷酸化蛋白表达。结果β-细辛醚协同TEN可增强APP/PS1双转基因小鼠的学习记忆功能,同时还能升高SOD、CAT和GSH-PX的活性,降低MDA含量,诱导Akt的蛋白表达,抑制GSK-3β的表达。结论远志汤有效成分即β-细辛醚+TEN可通过调控PI3K/Akt/GSK-3β信号通路,对APP/PS1双转基因小鼠氧化应激损伤发挥保护作用。

MiR-32-5p aggravates intestinal epithelial cell injury in pediatric enteritis induced by Helicobacter pylori

BACKGROUND Pediatric enteritis is one of the infectious diseases in the digestive system that causes a variety of digestive problems,including diarrhea,vomiting,and bellyache in children.Clinically,Helicobacter pylori(H.pylori)infection is one of the common factors to cause pediatric enteritis.It has been demonstrated that aberrant expression of microRNAs(miRNAs)is found in gastrointestinal diseases caused by H.pylori,and we discovered a significant increase of miR-32-5p in H.pylori-related pediatric enteritis.However,the exact role of miR-32-5p in it is still unknown.AIM To investigate the role of aberrant miR-32-5p in pediatric enteritis induced by H.pylori.METHODS MiR-32-5p expression was detected by quantitative real time-polymerase chain reaction.The biological role of miR-32-5p in H.pylori-treated intestinal epithelial cells was evaluated by Cell Counting Kit-8 assay and flow cytometry.The potential target of miR-32-5p was predicted with TargetScanHuman and verified by luciferase assay.The downstream mechanism of miR-32-5p was explored by using molecular biology methods.RESULTS We found that miR-32-5p was overexpressed in serum of H.pylori-induced pediatric enteritis.Further investigation revealed that H.pylori infection promoted the death of intestinal epithelial cells,and increased miR-32-5p expression.Moreover,miR-32-5p mimic further facilitated apoptosis and inflammatory cytokine secretion of intestinal epithelial cells.Further exploration revealed that SMAD family member 6(SMAD6)was the direct target of miR-32-5p,and SMAD6 overexpression partially rescued cell damage induced by H.pylori.The following experiments showed that miR-32-5p/SMAD6 participated in the apoptosis of intestinal epithelial cells induced by transforming growth factor-β-activated kinase 1(TAK1)-p38 activation under H.pylori infection.CONCLUSION Our work uncovered the crucial role of aberrant expression of miR-32-5p in H.pylori–related pediatric enteritis,and suggested that the TAK1-p38 pathway is involved in it.

Clinical nursing path after endoscopic submucosal dissection reduces the risk of postoperative complications

Objective： To investigate the effect of the nursing path on postoperative complications after endoscopic submucosal dissection （ESD）. Method： Patients＇ nursing paths for ESD were established based on a systematic analysis of relevant literature, previous clinical procedures and consultation with chief physicians from a gastroenterology department. Forty patients were divided into the observation or control group and were assigned to follow the nursing path or the conventional path after an ESD, respectively. Next, the incidence of postoperative complications of these two groups was measured, primarily assessing the occurrences of bleeding, perforation, infection, and anxiety. Results： The incidence of complications after ESD in the observation group was remarkably lower than that of the control group （P 〈 0.05）. Conclusion： The nursing path for ESD has a positive role in reducing certain frequent complications that occur after ESD, particularly infection and anxiety; in addition, the nursing path optimizes nursing care in patients with gastrointestinal stromal tumor.

Low thermal expansion and broad band photoluminescence of Zr0.1Al1.9Mo2.9V0.1O12

A new material of Zr0.1Al1.9Mo2.9V0.1O12 is synthesized by the traditional solid state synthesis method.The phase transition,coefficient of thermal expansion,and luminescence properties of Zr0.1Al1.9Mo2.9V0.1O12 are explored with Raman spectrometer,dilatometer,and x-ray diffraction(XRD)diffractometer.The results show that the Zr0.1Al1.9Mo2.9V0.1O12 possesses the strong broad-band luminescence characteristics almost in the whole visible region.The sample is crystallized in a monoclinic structure group of P21/a(No.14)crystallized at room temperature(RT).The crystal is changed from monoclinic to orthorhombic structure when the temperature increases to 463 K.The material has very low thermal expansion performance in a wide temperature range.Its excellent low thermal expansion and strong pale green light properties in a wide temperature range suggest its potential applications in light-emitting diode(LED)and other optoelectronic devices.

Phase transition and near-zero thermal expansion of Zr_(0.5)Hf_(0.5)VPO_7

The Zr（0.5）Hf（0.5）VPO7 is successfully synthesized by the solid-state method with near-zero thermal expansion. Powder x-ray diffraction（XRD）, Raman spectroscopy, thermal dilatometry, and scanning electron microscopy（SEM） are used to investigate the structure, the phase transition, and the coefficient of thermal expansion（CTE） of Zr（0.5）Hf（0.5）VPO7. The investigation results show that the samples are of the single cubic type with a space group of Pa3ˉ at room temperature（RT）.It can be inferred that the superstructure is transformed from the 3 × 3 × 3 superstructure to the 1 × 1 × 1 ideal crystal in a temperature range between 310 K and 323 K. The CTE is measured by a dilatometer to be 0.59 × 10^（-6） K^（-1）（310 K–673 K）. The values of intrinsic（XRD） and extrinsic（dilatometric） thermal expansion are both near zero. The results show that Zr（0.5）Hf（0.5）VPO7 has near-zero thermal expansion behavior over a wide temperature range.

Tricistronic hepatitis C virus subgenomic replicon expressing double transgenes

AIM: To construct a tricistronic hepatitis C virus (HCV) replicon with double internal ribosome entry sites (IRESes) of only 22 nucleotides for each, substituting the encephalomyocarditis virus (EMCV) IRESes, which are most often used as the translation initiation element to form HCV replicons.

Effects of Al component content on optoelectronic properties of Al_xGa_(1-x)N

Using density functional theory, the electronic structures, lattice constants, formation energies, and optical properties of AlxGa1-xN are determined with Al component content x in a range from 0 to 1. As x increases, the lattice constants decrease in e-exponential form, and the band gap increases with a band bending parameter b=0.3954. The N–Al interaction force in the（0001） direction is greater than the N–Ga interaction force, while the N–Al interaction force is less than the N–Ga interaction force in the（10ī0） direction. The formation energies under different Al component content are negative and increase with Al component content increasing. The static dielectric function decreases, the absorption edge has a blue shift, and the energy loss spectrum moves to high energy with the Al component content increasing.

Role of intestinal microbiota and metabolites in inflammatory bowel disease

Objective:The metabolites produced by the gut microbiota are of interest to scientists.The objective of this review was to provide an updated summary of progress regarding the microbiota and their metabolites and influences on the pathogenesis of inflammatory bowel disease(IBD).Data sources:The author retrieved information from the PubMed database up to January 2018,using various combinations of search terms,including IBD,microbiota,and metabolite.Study selection:Both clinical studies and animal studies of intestinal microbiota and metabolites in IBD were selected.The information explaining the possible pathogenesis of microbiota in IBD was organized.Results:In IBD patients,the biodiversity of feces/mucosa-associated microbiota is decreased,and the probiotic microbiota is also decreased,whereas the pathogenic microbiota are increased.The gut microbiota may be a target for diagnosis and treatment of IBD.Substantial amounts of data support the view that the microbiota and their metabolites play pivotal roles in IBD by affecting intestinal permeability and the immune response.Conclusions:This review highlights the advances in recent gut microbiota research and clarifies the importance of the gut microbiota in IBD pathogenesis.Future research is needed to study the function of altered bacterial community compositions and the roles of metabolites.

Stress Responsive Zinc-finger Protein Gene of Populus euphratica in Tobacco Enhances Salt Tolerance

The Populus euphratica stress responsive zinc-finger protein gene PSTZ, which encodes a protein including typical Cys2/His2 zinc finger structure, was isolated by reverse transcription-polymerase chain reaction from P. euphratica. Northern hybridization revealed that its expression was induced under drought and salt stress conditions. To examine its function, cDNA of the PSTZ gene, driven by the cauliflower mosaic virus 35S promoter, was cloned into a plant expression vector pBin438 and introduced into tobacco plants. Transgenic tobacco showed an enhanced salt tolerance, suggesting that PSTZ may play a role in plant responsiveness to salt stress.

Study of Simplified Coma Scales： Acute Stroke Patients with Tracheal Intubation

Background： Whether the Glasgow Coma Scale （GCS） can assess intubated patients is still a topic of controversy. We compared the test performance of the GCS motor component （GCS-M）/Simplified Motor Score （SMS） to the total of the GCS in predicting the outcomes of intubated acute severe cerebral vascular disease patients. Methods： A retrospective analysis of prospectively collected observational data was performed. Between January 2012 and October 2015, 106 consecutive acute severe cerebral vascular disease patients with intubation were included in the study. GCS, GCS-M, GCS eye-opening component, and SMS were documented on admission and at 24, 48, and 72 h after admission to Neurointensive Care Unit （NCU）. Outcomes were death and unfavorable prognosis （modified Rankin Scale： 5-6） at NCU discharge. The receiver operating characteristic （ROC） curve was obtained to determine the prognostic performance and best cutoff value for each scoring system. Comparison of the area under the ROC curves （AUCs） was performed using the Z-test.Results： Of 106 patients included in the study, 41 （38.7%） patients died, and 69 （65.1%） patients had poor prognosis when discharged from NCU. The four time points within 72 h of admission to the NCU were equivalent for each scale＇s predictive power, except that 0 h was the best for each scale in predicting outcomes of patients with right-hemisphere lesions. Nonsignificant difference was found between GCS-M AUCs and GCS AUCs in predicting death at 0 h （0.721 vs. 0.717, Z = 0.135, P = 0.893） and 72 h （0.730 vs. 0.765, Z = 1.887, P = 0.060）, in predicting poor prognosis at 0 h （0.827 vs. 0.819, Z = 0.395, P = 0.693）, 24 h （0.771 vs. 0.760, Z = 0.944, P = 0.345）, 48 h （0.732 vs. 0.741, Z= 0.593, P= 0.590）, and 72 h （0.775 vs. 0.780, Z= 0.302, P= 0.763）. AUCs in predicting death for patients with left-hemisphere lesions ranged from 0.700 to 0.804 for GCS-M and from 0.700 to 0.824 for GCS, in predicting poor prognosis ranged from 0.841 to 0.969 for GCS-M and from 0.875 to 0.969 for GCS, with no significant difference between GCS-M AUCs and GCS AUCs within 72 h （P 〉 0.05）. No significant difference between GCS-M AUCs and GCS AUCs was found in predicting death （0.964 vs. 0.964, P = 1.000） and poor prognosis （ 1.000 vs. 1.000, P = 1.000） for patients with right-hemisphere lesions at 0 h. AUCs in predicting death for patients with brainstem or cerebella were poor for GCS-M （〈0.700）, in predicting poor prognosis ranged from 0.727 to 0.801 for GCS-M and from 0.704 to 0.820 for GCS, with no significant difference between GCS-M AUCs and GCS AUCs within 72 h （P 〉 0.05）. The SMS AUCs （〈0.700） in predicting outcomes were poor. Conclusions： The GCS-M approaches the same test performance as the GCS in assessing the prognosis ofintubatcd acute severe cerebral vascular disease patients. The GCS-M could be accurately and reliably applied in patients with hemisphere lesions, but caution must be taken for patients with brainstem or cerebella lesions.

Psychological reactions of healthcare workers deployed to Wuhan from Shanxi province and how they cope during coronavirus disease 2019(COVID-19)outbreak

To the Editor:Since the outbreak of coronavirus disease 2019(COVID-19),a large number of healthcare workers(HCWs)volunteered to leave their familiar working and living environments to travel to Hubei province to undertake emergency response work.For most medical workers who traveled to Hubei province,this was their first time participating in such a crisis situation.Previous studies have reported that HCWs face a double blow of high-intensity work and high psychological pressure,making them particularly prone to mental health difficulties.