Asymptomatic low-grade appendiceal mucinous neoplasm:A case report

BACKGROUND Low-grade appendiceal neoplasms(LAMN)are characterized by low incidence and atypical clinical presentations,often leading to misdiagnosis as acute or chronic appendicitis before surgery.The primary diagnostic tool for LAMN is abdominal computed tomography(CT)imaging.Surgical resection remains the cornerstone of LAMN management,necessitating en bloc tumor excision to minimize the risk of iatrogenic rupture.Laparoscopy,known for its minimal invasiveness,reduced postoperative discomfort,and expedited recovery,is a safe and reliable approach for LAMN treatment.Despite the possibility of pseudomyxoma peritonei development,appendectomy and partial appendectomy generally result in negative tumor margins and favorable outcomes,which can be attributed to the disease’s slow growth and lower malignancy.CASE SUMMARY A 71-year-old male patient was admitted to our hospital with a pelvic spaceoccupying lesion detected 1 mo prior.Physical examination showed a soft abdomen without tenderness or rebound and no palpable masses.No shifting dullness was noted,and digital rectal examination revealed no palpable mass.Enteroscopy revealed a raised,smooth-surfaced mass measuring 3.0 cm in the cecum.Abdominal contrast-enhanced CT showed a markedly thickened and dilated appendix with visible cystic shadows.Laparoscopic surgery was performed and revealed a significantly dilated appendix,leading to laparoscopic resection of the appendix and part of the cecum.Post-surgical pathologic analysis confirmed LAMN.The patient received symptomatic and supportive post-operative care and was discharged on postoperative day 4 without complications such as abdominal bleeding,intestinal obstruction,or incision infection.No tumor recurrence was observed during a 7-mo follow-up period.CONCLUSION LAMN is a rare disease that lacks specific clinical manifestations.Abdominal CT plays a crucial role in diagnosing LAMN,and laparoscopic surgery is a safe and effective diagnostic and therapeutic approach.

Low-grade myofibrosarcoma of the maxillary sinus:Two case reports

BACKGROUND Low-grade myofibroblastic sarcoma(LGMS)is an extremely rare tumor characterized by the malignant proliferation of myofibroblasts.LGMS most commonly develops in adults,predominantly in males,in the head and neck region,oral cavity,especially on the tongue,mandible,and larynx.This article presents 2 cases of LGMS localized to the maxillary sinus and provides an overview of the available literature.CASE SUMMARY Two patients with LGMS located in the maxillary sinus underwent surgery at the Department of Head and Neck Surgery.Case 1:A 46-year-old patient was admitted to the clinic with suspected LGMS recurrence in the right maxillary sinus(rT4aN0M0),with symptoms of pain in the suborbital area,watering of the right eye,thick discharge from the right nostril,and augmented facial asymmetry.After open biopsy-confirmed LGMS,the patient underwent expanded maxillectomy of the right side with immediate palate reconstruction using a microvascular skin flap harvested surgically from the middle arm.The patient qualified for adjuvant radiotherapy for the postoperative bed,with an additional margin.Currently,the patient is under 1.5 years of observation with no evidence of disease.Case 2:A 45-year-old man was admitted to our clinic with facial asymmetry,strabismus,exophthalmos,and visual impairment in the right eye.Six months earlier,the patient had undergone partial jaw resection at another hospital for fibromatosis.A contrast-enhanced computed tomography scan revealed a tumor mass in the postoperative log after an earlier procedure.An open biopsy confirmed lowgrade fibrosarcoma(rT4aN0M0).The patient qualified for an extended total right maxillectomy with orbital excision and right hemimandibulectomy with immediate microvascular reconstruction using an anterolateral thigh flap.The patient subsequently underwent adjuvant radiotherapy to the postoperative area.After 9 months,recurrence occurred in the right mandibular arch below the irradiated area.The lesion infiltrated the base of the skull,which warranted the withdrawal of radiotherapy and salvage surgery.The patient qualified for palliative chemotherapy with a regimen of doxorubicin+dacarbazine+cyclophosphamide and palliative radiotherapy for bone metastases.The patient died 26 months after surgical treatment.The cases have been assessed and compared with cases in the literature.CONCLUSION No specific diagnostic criteria or treatment strategies have been developed for LGMS.The treatment used for LGMS is the same as that used for sinonasal cancer radical tumor excision;adjuvant radiotherapy or chemoradiotherapy should also be considered.They have low malignant potential but are highly invasive,tend to recur,and metastasize to distant sites.Patients should undergo regular follow-up examinations to detect recurrence or metastasis at an early stage.Patients should be treated and observed at the highest referral centers.

Effect of CO_2 and N_2 on microbial community changes during column bioleaching of low-grade high pyrite-bearing chalcocite ore

Simulated heap bioleaching of low-grade high pyrite-bearing chalcocite ore was conducted at 40 °C with aeration of CO_2 and N_2.Ore samples were collected at day 43,64,85,106 and subjected to microbial community analysis by 16S rRNA gene clone library.Phylogenetic analyses of 16S rDNA fragments revealed that the retrieved sequences are mainly related to genus Acidithiobacillus,Leptospirillum and Sulfobacillus.Aeration of CO_2 and N_2 significantly impacted the microbial community composition.When CO_2 was aerated,the proportion of genus Acidithiobacillus considerably increased,whereas the proportion of genus Leptospirillum and genus Sulfobacillus declined.However,with the aeration of N_2,the proportion of genus Acidithiobacillus and Leptospirillum increased,but genus Sulfobacillus decreased.When there was no aeration,the microbial community was similar to the inocula with the proportion of genus Leptospirillum mounted.These results indicated that the limitation of oxygen could change the bioleaching microbial community and the aeration of CO_2 and N_2 was favourable for the growth of sulfur-oxidizer(At.caldus) and iron-oxidizer(L.ferriphilum) respectively,which could be used for the regulation of microorganisms' role in mineral bioleaching.

Effect of hydrogen peroxide on selective flotation of chalcocite and enargite

Enargite is typically associated with chalcocite.Owing to the similarity in the flotation behaviors of these minerals,both minerals are reported to concentrate in the conventional flotation circuit.However,inorganic arsenic in enargite can decrease the copper concentrate quality and increase the operating cost of processing this concentrate.Separating these minerals is important for cleaner copper production to avoid these effects.In this context,this study investigated the effect of hydrogen peroxide(H_(2)O_(2))treatment on the flotation behavior of chalcocite and enargite.Flotation tests of pure and mixed minerals indicated that H_(2)O_(2)treatment reduced the floatability of chalcocite and enargite by forming sulfate and copper hydroxide on their surfaces.Despite the detrimental effect of the H_(2)O_(2)treatment,there was a narrow window of H_(2)O_(2)concentration for separating both minerals,in which enargite floated and chalcocite was depressed.This selective flotation behavior was caused by the rapid adsorption of potassium amyl xanthate(KAX)and lower surface oxidation of enargite compared with that of chalcocite.

Thermally Chargeable Proton Capacitor Based on Redox-Active Effect for Energy Storage and Low-Grade Heat Conversion

Thermal energy is abundantly available in our daily life and industrial production,and especially,low-grade heat is often regarded as a byproduct.Collecting and utilizing this ignored energy by low-cost and simple technologies may become a smart countermeasure to relieve the energy crisis.Here,a unique device has been demonstrated to achieve high value-added conversion of low-grade heat by introducing redox-active organic alizarin(AZ)onto N-doped hollow carbon nanofibers(N–HCNF)surface.As-prepared N–HCNF/AZ can deliver a high specific capacitance of 514.3 F g^(-1)(at 1 A g^(-1))and an outstanding rate capability of 60.3%even at 50 A g^(-1).Meanwhile,the assembled symmetric proton capacitor can deliver a high energy density of 28.0 Wh kg^(-1) at 350.0 W kg^(-1) and a maximum power density of 35.0 kW kg^(-1) at 17.0 Wh kg^(-1).Significantly,the thermally chargeable proton capacitors can attain a surprisingly high Seebeck coefficient of 15.3 mV K^(-1) and a power factor of 6.02µW g^(-1).Taking advantage of such high performance,a satisfying open-circuit voltage of 481.0 mV with a temperature difference of 54 K is achieved.This research provides new insights into construction of high value-added energy systems requiring high electrochemical performances.

Anlotinib in combination with pembrolizumab for low-grade myofibroblastic sarcoma of the pancreas: A case report

BACKGROUND Low-grade myofibroblastic sarcoma(LGMS)is a rare spindle cell sarcoma espe-cially in the pancreas,with myofibroblastic differentiation.Hitherto,only a few cases have been reported.CASE SUMMARY Herein,we report a case involving the discovery of a pancreatic mass detected during a routine physical examination.Subsequent imaging and pathological tests of the patient led to the diagnosis of LGMS of the pancreas.Following surgical intervention,the patient experienced recurrence and metastasis.Conventional treatment is not effective for postoperative recurrent pancreatic LGMS with multiple metastases.After communicating with the patients and their families,informed consent was obtained for the treatment of anlotinib combined with pembrolizumab.Evaluation of imaging and clinical symptoms post-treatment revealed a relatively favorable response to the combination of anlotinib and pembrolizumab.CONCLUSION Based on the comprehensive literature review,our report aimed to provide evidence for a better understanding of the disease characteristics,diagnostic criteria,imaging findings,and identification of LGMS.And explore novel treatment strategies for this disease.

Mechanism study on flotation separation of molybdenite from chalcocite using thioglycollic acid as depressant

Effects of collectors(butyl xanthate(BX), O-isopropyl-N-sulfur ethyl carbamate(Z-200) and emulsified kerosene), dereagent(sodium sulfide) and depressant thioglycollic acid(TGA) on the flotation of chalcocite and molybdenite were investigated through flotation. The first principle theory was adopted to understand the difference of their surfaces and reaction between minerals and reagents. Results of flotation tests revealed that selectivity of emulsified kerosene is the best of three collectors in separation of chalcocite and molybdenite, though the others also display excellent collecting properties. Sodium sulfide can effectively remove collectors adsorbed on chalcocite surface, and TGA is an effective depressant of chalcocite at pH 8-9. Through first principle study, molybdenite displays relatively stronger covalence property while bonding interaction between copper atoms in chalcocite enhanced its ionicity. Bonding interaction is weaker in reaction of TGA and molybdenite, so it shows higher hydrophobicity and better flotability. Therefore, TGA is an effective inhibitor in the separation.

Linking leach chemistry and microbiology of low-grade copper ore bioleaching at different temperatures

The effects of temperature on chalcocite/pyrite oxidation and the microbial population in the bioleaching columns of a low-grade chalcocite ore were investigated in this study. Raffinate from the industrial bioleaching heap was used as an irrigation solution for columns operated at 20, 30, 45, and 60℃. The dissolution of copper and iron were investigated during the bioleaching processes, and the microbial community was revealed by using a high-throughput sequencing method. The genera of Ferroplasma, Acidithiobacillus, Leptospirillum, Acidiplasma, and Sulfobacillus dominated the microbial community, and the column at a higher temperature favored the growth of moderate thermophiles. Even though microbial abundance and activity were highest at 30℃, the column at a higher temperature achieved a much higher Cu leaching efficiency and recovery, which suggested that the promotion of chemical oxidation by elevated temperature dominated the dissolution of Cu. The highest pyrite oxidation percentage was detected at 45℃. Higher temperature resulted in precipitation of jarosite in columns, especially at 60℃. The results gave implications to the optimization of heap bioleaching of secondary copper sulfide in both enhanced chalcocite leaching and acid/iron balance, from the perspective of leaching temperature and affected microbial community and activity.

Hepatic steatosis,low-grade chronic inflammation and hormone/growth factor/adipokine imbalance

Non-alcoholic fatty liver disease (NAFLD), a further expression of metabolic syndrome, strictly linked to obesity and diabetes mellitus, is characterized by insulin resistance (IR), elevated serum levels of free fatty acids and fatty infi ltration of the liver, which is known as hepatic steatosis. Hepatocyte apoptosis is a key feature of this disease and correlates with its severity. Free-fatty-acidinduced toxicity represents one of mechanisms for the pathogenesis of NAFLD and hormones, growth factors and adipokines influence also play a key role. This review highlights the various pathways that contribute to the development of hepatic steatosis. Circulating concentrations of inflammatory cytokines are reckoned to be the most important factor in causing and maintaining IR. Low-grade chronic inflammation is fundamental in the progression of NAFLD toward higher risk cirrhotic states.

Low-grade myofibroblastic sarcoma of the palate

Low-grade myofibroblastic sarcoma （LGMS） is a rare, malignant tumor with myofibroblastic differentiation. Despite it being classified as a distinct entity by the World Health Organization, a few cases were reported in the oral and maxillofacial region. Here, a LGMS developed on the palate of a 73-year-old man who presented with a 1-cm tumor on the posterior border of the palate. Based on the histological and immunohistochemical features, a diagnosis of LGMS was established. The tumor was resected, and no recurrence was observed over 2 years. Although the tongue is the most preferred site for LGMS, it may occur in any region of the oral cavity.

Optimal management of biopsy-proven low-grade gastric dysplasia

Gastric adenocarcinoma generally culminates via the inflammation-metaplasia-dysplasia-carcinoma sequence progression. The prevalence of gastric adenomas shows marked geographic variation. Recently, the rate of diagnosis of low-grade dysplasia(LGD) has increased due to increased use of upper endoscopy. Many investigators have reported that gastric highgrade dysplasia has high potential for malignancy and should be removed; however, the treatment for gastric LGD remains controversial. Although the risk of LGD progression to invasive carcinoma has been reported to be inconsistent, progression has been observed during follow-up. Additionally, the rate of upgraded diagnosis in biopsy-proven LGD is high. Therefore, endoscopic resection(ER) may be useful in the treatment and diagnosis of LGD, especially if lesions are found to have risk factors for upgraded histology after ER, such as large size, surface erythema or depressed morphology. Fatal complications in endoscopic submucosal dissection(ESD) are extremely low and its therapeutic and diagnostic outcomes are excellent. Therefore, ESD should be applied preferentially instead of endoscopic mucosal resection.

Even low-grade inflammation impacts on small intestinal function

Independent of the cause and location,inflammation-even when minimal-has clear effects on gastrointestinal morphology and function.These result in altered digestion,absorption and barrier function.There is evidence of reduced villus height and crypt depth,increased permeability,as well as altered sugar and peptide absorption in the small intestine after induction of inflammation in experimental models,which is supported by some clinical data.Identification of inflammatory factors which may promote the process of gastrointestinal dysfunction as well as clinical research to verify experimental observations of inflammatory modulation of gastrointestinal function are required.Moreover,nutritional strategies to support functional restitution are needed.

Hydrometallurgical leaching and kinetic modeling of low-grade manganese ore with banana peel in sulfuric acid

Manganese was leached from a low-grade manganese ore(LGMO)using banana peel as the reductant in a dilute sulfuric acid medium.The effects of banana peel amount,H2SO4 concentration,reaction temperature,and time on Mn leaching from the complex LGMO were studied.A leaching efficiency of~98%was achieved at a leaching time of 2 h,banana peel amount of 4 g,leaching temperature of 120°C,manganese ore amount of 5 g,and sulfuric acid concentration of 15vol%.The phase,microstructural,and chemical analyses of LGMO samples before and after the leaching process confirmed the successful leaching of manganese.Furthermore,the leaching process followed the shrinking core model and the leaching rate was controlled by a surface chemical reaction(1−(1−x)^1/3=kt)mechanism with an apparent activation energy of 40.19 kJ·mol^−1.

Recovery of zinc from low-grade zinc oxide ores by solvent extraction

The recovery of zinc from low-grade zinc oxide ores with solvent extraction-electrowinning technique was investigated by using D2EHPA as extractant and 260 # kerosene as diluent. The results show that it is possible to selectively leach zinc from the ores by heap leaching. The zinc concentration of leach solution in the first leaching cycle is 32.57 g/L, and in the sixteenth cycle the zinc concentration is 8.27g/L after solvent extraction. The leaching solution is subjected to solvent extraction, scrubbing and selective stripping for enrichment of zinc and removal of impurities. The pregnant zinc sulfate solution produced from the stripping cycle is suitable for zinc electrowinning. Extra-pure zinc metal was obtained in the electrowinning test under conventional conditions.

Suspension calcination and alkali leaching of low-grade high-sulfur bauxite:Desulfurization, mineralogical evolution and desilication

To enable the utilization of low-grade and high-sulfur bauxite, the suspension calcination was used to remove the sulfur and the activate silica minerals, and the calcinated bauxite was subjected to a desilication process in Na OH solution under atmospheric pressure. The desulfurization and desilication properties and mineralogical evolution were studied by X-ray diffraction, thermogravimetry–differential thermal analysis, scanning electron microscopy, and FactSage methods. The results demonstrate that the suspension calcination method is efficient for sulfur removal: 84.21% of S was removed after calcination at 1000°C for 2 min. During the calcination process, diaspore and pyrite were transferred to α-Al2O3, magnetite, and hematite. The phase transformation of pyrite follows the order FeS2 → Fe3O4 → Fe2O3, and the iron oxides and silica were converted into iron silicate. In the alkali-soluble desilication process, the optimum condition was an alkali solution concentration of 110 g/L, a reaction time of 20 min, and a reaction temperature of 95°C. The corresponding desilication ratio and alumina loss ratio were 44.9% and 2.4%, respectively, and the alumina-to-silica mass ratio of the concentrate was 7.9. The Al2O3·2SiO2, SiO2, and Al2O3 formed during the calcination process could react with Na OH solution, and their activity decreased in the order of Al2O3·2 SiO2, SiO2, and Al2O3.

Research on new beneficiation process of low-grade magnesite using vertical roller mill

We investigated whether the vertical roller mill can be efficiently used in the beneficiation of low-grade magnesite and whether it can improve upon the separation indices achieved by the ball mill.We conducted experiments involving the reverse flotation and positive flotation of low-grade magnesite to determine the optimum process parameters,and then performed closed-circuit beneficiation experiments using the vertical roller mill and ball mill.The results show that the optimum process parameters for the vertical roller mill are as follows:a grinding fineness of 81.6wt%of particles less than 0.074 mm,a dodecyl amine(DDA)dosage in magnesite reverse flotation of 100 g·t?1,and dosages of Na2CO3,(NaPO3)6,and NaOL in the positive flotation section of 1000,100,and 1000 g·t?1,respectively.Compared with the ball mill,the use of the vertical roller mill in the beneficiation of low-grade magnesite resulted in a 1.28%increase in the concentrate grade of MgO and a 5.88%increase in the recovery of MgO.The results of our causation mechanism analysis show that a higher specific surface area and greater surface roughness are the main reasons for the better flotation performance of particles ground by the vertical roller mill in the beneficiation of lowgrade magnesite.

Very Low-Grade Metamorphism of Clastic Rocks from the Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang in Northeastern Hunan Province and Its Geological Implications

This study uses illite crystallinity,chlorite crystallinity,illite polytypes,the b0 cell-dimension of K-white mica,clay mineral assemblages and mineral geothermo-geobarometers to investigate the overprint of diagenesis and metamorphism on the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang in northeastern Hunan Province,China.Illite crystallinity Kbler index（KI） of the 〈2μm fractions ranges from 0.225 to 0.485°Δ2θ while chlorite crystallinity Arkai index（AI） ranges from 0.244 to 1.500°Δ2θ.This indicates that the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang were overprinted with diagenesis and anchi- to epimetamorphism.Peak metamorphic temperature is estimated with the IV site chlorite geothermometer roughly at 360℃.The b0 cell dimension values of illites（K-mica） range from 0.9002 to 0.9054 nm and,on average,at 0.9030 nm for the Meso-Neoproterozoic.Based on cumulative frequency curves of illite（K-mica） b0 cell dimension,the peak metamorphic pressure of the MesoNeoproterozoic along the profile Yueyang-Linxiang is derived of an intermediate pressure type.Most illites occur in the 2M1 polytype and some of them in a mixture of 2M1＋1M types especially those in the Paleozoic.This result partly agrees with the conclusion of the lower greenschist and greenschist facies of the Lengjiaxi and Banxi Groups.However,it is not agreed with the sedimentary cover from the Sinian to the Lower Paleozoic or from the Banxi Group to the Lower Paleozoic.Crustal thickening due to ＂collision＂ between the Yangtze and Cathaysia blocks led to an increase in the thickness of the Meso-Neoproterozoic to ca.14 km and resulted in a temperature increase in those rocks due to burial.The very low grade to low grade metamorphism overprinting the Meso-Neoproterozoic implies that the so called ＂Chiangnania or Jiangnan orogen＂ was no relative with the ＂Grenvillian orogeney;instead,it might be a continuous amalgamation product between the Yangtze and Cathaysia blocks.

Chalcocite(bio)hydrometallurgy-current state,mechanism,and future directions:A review

There has been a strong interest in technologies suited for mining and processing of low-grade ores because of the rapid depletion of mineral resources in the world.In most cases,the extraction of copper from such raw materials is achieved by applying the leaching procedures.However,its low extraction efficiency and the long extraction period limit its large-scale commercial applications in copper recovery,even though bioleaching has been widely employed commercially for heap and dump bioleaching of secondary copper sulfide ores.Overcoming the technical challenges requires a better understanding of leaching kinetics and on-site microbial activities.Herein,this paper reviews the current status of main commercial biomining operations around the world,identifies factors that affect chalcocite dissolution both in chemical leaching and bioleaching,summarizes the related kinetic research,and concludes with a discussion of two on-site chalcocite heap leaching practices.Further,the challenges and innovations for the future development of chalcocite hydrometallurgy are presented in the end.

Acid equilibrium during bioleaching of alkaline low-grade sulfide copper ore

This article reports the study on acid equilibrium during bioleaching of alkaline low-grade copper sulfide ore. Adding auxiliary agents 1# （sulfur） and 2# （pyrite） makes bacterial leaching of copper and acid production carried out simultaneously because the auxiliary agents can be oxidized by bacteria and the oxidation products involve acid. The acid required for dissolving alkaline gangue during bacterial leaching is produced, and acid equilibrium is reached during the ore bio-leaching. The recovery of copper reaches more than 95%.