Vonoprazan-amoxicillin dual therapy for Helicobacter pylori eradication in Chinese population:A prospective,multicenter,randomized,two-stage study

BACKGROUND The efficacy of Vonoprazan-amoxicillin dual therapy(VAT)in the treatment of Helicobacter pylori(H.pylori)is controversial.AIM To evaluate the efficacy of VAT in the Chinese population.METHODS This prospective,multicenter,randomized,open-label,and two-stage study was conducted at 23 centers in Fujian,China(May 2021-April 2022).H.pylori-infected patients were randomized to bismuth quadruple therapy(BQT),BQT-Vonoprazan(BQT-V),seven-day VAT(VAT-7),ten-day VAT(VAT-10),and fourteen-day VAT(VAT-14)groups.The primary endpoint was the H.pylori eradication rate.The secondary endpoint was the frequency of adverse events.This study was registered with the Chinese Clinical Trial Registry,ChiCTR2100045778.RESULTS In the first stage,VAT-7 and BQT-V groups were selected for early termination because less than 23 among 28 cases were eradicated.In the second stage,the eradication rates for BQT,VAT-10,and VA-14 were 80.2%[95%confidence interval(95%CI):71.4%-86.8%],93.2%(86.6%-96.7%),92.2%(85.3%-96.0%)in the intention-to-treat(ITT)analysis,and 80.9%(95%CI:71.7%-87.5%),94.0%(87.5%-97.2%),and 93.9%(87.4%-97.2%)in the per-protocol analysis.The ITT analysis showed a higher eradication rate in the VAT-10 and VAT-14 groups than in the BQT group(P=0.022 and P=0.046,respectively).The incidence of adverse events in the VAT-10 and VAT-14 groups was lower than in the BQT group(25.27%and 13.73%vs 37.62%,respectively;P<0.001).CONCLUSION VAT with a duration of 10 or 14 days achieves a higher eradication rate than the BQT,with a more tolerable safety profile in H.pylori-infected patients in Fujian.Huang XP et al.VAT for H.pylori eradication.

The long-lived partial melting of the Greater Himalayas in southern Tibet, constraints from the Miocene Gyirong anatectic pegmatite and its prospecting potential for rare element minerals

The Cenozoic Himalayan leucogranite-pegmatite belt has been a hotspot for rare metal exploration in recent years.To determine the genesis of the pegmatite in the Himalayan region and its relationship with the Greater Himalayan Crystalline Complex(GHC),the Gyirong pegmatite in southern Tibet was chosen for geochronological and geochemical studies.The dating analyses indicate that the U-Th-Pb ages of zircon,monazite,and xenotime exhibit large variations(38.6‒16.1 Ma),with the weighted average value of the four youngest points is 16.5±0.3 Ma,which indicates that the final stage of crystallization of the melt occurred in the Miocene.The age of the muscovite Ar-Ar inverse isochron is 15.2±0.4 Ma,which is slightly later than the intrusion age,showing that a cooling process associated with rapid denudation occurred at 16‒15 Ma.TheεHf(t)values of the Cenozoic anatectic zircons cluster between−12 and−9 with an average of−11.4.The Gyirong pegmatite shows high contents of Si,Al,and K,a high Al saturation index,and low contents of Na,Ca,Fe,Mn,P,Mg,and Ti.Overall,the Gyirong pegmatite is enriched in Rb,Cs,U,K,Th and Pb and depleted in Nb,Ta,Zr,Ti,Eu,Sr,and Ba.The samples show a high 87Sr/86Sr(16 Ma)ratio of ca.0.762 and a lowεNd(16 Ma)value of−16.0.The calculated average initial values of 208Pb/204Pb(16 Ma),207Pb/204Pb(16 Ma)and 206Pb/204Pb(16 Ma)of the whole rock are 39.72,15.79 and 19.56,respectively.The Sr-Nd-Pb-Hf isotopic characteristics of the Gyirong pegmatite are consistent with those of the GHC.This study concludes that the Gyirong pegmatite represents a typical crustal‒derived anatectic pegmatite with low metallogenic potential for rare metals.The Gyirong pegmatite records the long‒term metamorphism and partial melting process of the GHC,and reflects the crustal thickening caused by thrust compression at 39‒29 Ma and the crustal thinning induced by extensional decompression during 28‒15 Ma.

Geology and mineralization of the Pulang supergiant porphyry copper deposit(5.11 Mt)in Shangri-la,Yunnan Province,China:A review

The porphyry copper belt in the Geza island arc in southwestern China is the only Indosinian porphyry copper metallogenic belt that has been discovered and evaluated so far.The Pulang porphyry copper deposit(also referred to as the Pulang deposit)in this area has proven copper reserves of 5.11×106 t.This deposit has been exploited on a large scale using advanced mining methods,exhibiting substantial economic benefit.Based on many research results of previous researchers and the authors’team,this study proposed the following key insights.(1)The Geza island arc was once regarded as an immature island arc with only andesites and quartz diorite porphyrites occurring.This understanding was overturned in this study.Acidic endmember components such as quartz monzonite porphyries and quartz monzonite porphyries have been identified in the Geza island arc,and the mineralization is mainly related to the magmatism of quartz monzonite porphyries.(2)Complete porphyry orebodies and large vein orebodies have developed in the Pulang deposit.Main orebody KT1 occurs in the transition area between the potassium silicate alteration zone of quartz monzonite porphyries and the sericite-quartz alteration zone.Most of them have developed in the potassium silicate alteration zone.The main orebody occurs as large lenses at the top of the hanging wall of rock bodies,with an engineering-controlled length of 1920 m and thickness of 32.5‒630.29 m(average:187.07 m).It has a copper grade of 0.21%-1.56%(average:0.42%)and proven copper resources of 5.11×10^(6) t,which are associated with 113 t of gold,1459 t of silver,and 170×10^(3) t of molybdenum.(3)Many studies on diagenetic and metallogenic chronology,isotopes,and fluid inclusions have been carried out for the Pulang deposit,including K-Ar/Ar-Ar dating of monominerals(e.g.,potassium feldspars,biotites,and amphiboles),zircon U-Pb dating,and molybdenite Re-Os dating.The results show that the porphyries in the Pulang deposit are composite plutons and can be classified into pre-mineralization quartz diorite porphyrites,quartz monzonite porphyries formed during the mineralization,and post-mineralization granite porphyries,which were formed at 223±3.7 Ma,218±4 Ma,and 207±3.9 Ma,respectively.The metallogenic age of the Pulang deposit is 213‒216 Ma.(4)The petrogeochemical characteristics show that the Pulang deposit has the characteristics of volcanic arc granites.The calculation results of trace element contents in zircons show that quartz monzonite porphyries and granite porphyries have higher oxygen fugacity.The isotopic tracing results show that the diagenetic and metallogenic materials were derived from mixed crust-and mantle-derived magmas.