Gastrointestinal tract and viral pathogens

Viral gastroenteritis is the most common viral illness that affects the gastro-intestinal(GI)tract,causing inflammation and irritation of the lining of the stomach and intestines.Common signs and symptoms associated with this condition include abdominal pain,diarrhea,and dehydration.The infections commonly involved in viral gastroenteritis are rotavirus,norovirus,and adenovirus,which spread through the fecal-oral and contact routes and cause non-bloody diarrhea.These infections can affect both immunocompetent and immunocompromised individuals.Since the pandemic in 2019,coronavirus gastroenteritis has increased in incidence and prevalence.Morbidity and mortality rates from viral gastroenteritis have declined significantly over the years due to early recognition,treatment with oral rehydration salts,and prompt vaccination.Improved sanitation measures have also played a key role in reducing the transmission of infection.In addition to viral hepatitis causing liver disease,herpes virus,and cytomegalovirus are responsible for ulcerative GI disease.They are associated with bloody diarrhea and commonly occur in im-munocompromised individuals.Hepatitis viruses,Epstein-Barr virus,herpesvirus 8,and human papillomavirus have been involved in benign and malignant diseases.This mini review aims to list different viruses affecting the GI tract.It will cover common symptoms aiding in diagnosis and various important aspects of each viral infection that can aid diagnosis and management.This will help primary care physicians and hospitalists diagnose and treat patients more easily.

The therapeutic effects of recombinant adenovirus RA538 on human gastric carcinoma cells in vitro and in vivo

AIM To evaluate the potential of RA-538 genetherapy for gastric carcinoma.METHODS Human gastric carcinoma cell lineSGC7901 treated with Ad-RA538 or Ad-LacZ wereanalysed by X-gal stain,MTT,DNA ladder,Tunel,flow cytometric analysis,PCR,andWestern Blot in vitro.The tumorigenicity andexperimental therapy in nude mice model wereassessed in vivo.RESULTS Ad-LacZ could efficiently transferthe LacZ gene into SGC7901 cells.X-gal-positivecells at MOI 25,50,100,and 200 were 90%,100%,100%,and 100% respectively.Ad-RA538could strongly inhibit cell growth and inducedapoptosis in SGC7901 cells.The proliferation ofthe Ad-RA538-infected SGC7901 cells wasreduced by 76.3%.The mechanism of killing ofgastric carcinoma cells by Ad-RA538 was foundto be apoptosis by DNA ladder,Tunel and flowcytometric analysis.The tumorigenicity in nudemice using Ad-RA538 showed that all three micefailed to form tumor from 7 to 30 days comparedwith Ad-LacZ and parent SGC7901 cells.Experimental therapy on the nude mice modelbearing subcutaneous tumor of SGC790| cells showed that intratumor instillation of Ad-RA538inhibited the growth of the tumors.Ad-RA538-treated tumors were inhibited by 60.66 %,compared with that of the tumor injected withAd-LacZ and mock.CONCLUSION The expression of Ad-RA538 can inhibit growth and induce apoptosis of gastric cancer cell in vitro and in vivo. Ad-RA538 can be used potentially in gene therapy for gastric carcinoma.

Pathogenic and pathological characteristic of new type gosling viral enteritis first observed in China

AIM To study the purifying method and characteristics of neW gosling viral enteritis virus (NGVEV), the etiological agent of new gosling viral enteritis (NGVE) which was first recognized in China, as well as the pathomorphological davelapment in goslings infected artificially with NGVEV.``of treatment with chloroform and ammonium sulfate precipitation, dialysis to remove the sulfate radical and ammonium ion and separation by gel filtration Sichuan goslings were orally administered with NGVEV and 24hr later 2 birds were randomly selected and killed at 24hr intervals Until death occurred. Specimens(duodenum, ileum,liver, heart, kidney, spleen, lung, proventriculus, pancreas,esophagus, and the intestinal embolus) were taken until all birds in this group died and were sectioned and stained with hemotoxylin and ensin and studied by light microscope.``RESULTS NGVEV shared the typical characteristics of Adenovirus and which structural proteins consisted of 15polypsptides. Necrosis and sloughing of the epithelial cells covering the villus tips of the duodanum were first observed in goslings 2 days postinfectien artificially with NGVEV. With the progress of infection, this lesion rapidly occurred in the epithelium at the base of the villus and with infiltration of the inflammatory cells, the jejunum tended to be involved. With the intensification of rnucnsa necrosis and inflammatory exudation of the small intestine, fibrinenecrotic enteritis was further developed and embolus composed of either intestinal contents wrapped by pseudomembrane or of the mixture of fibrous exudate and necrotic intestinal rnucoes were observed in the middle-lower part of the small intestine. This structure occluded the intestinal tract and made the intestine dilated in appearance. The intestinal glandular cells underwent degeneration, necrosis and might be found sloughed into the lumen. Hemorrhage and hyperemia could be observed on the lung and kidney . Epithelial cells of the renal tubular underwent degeneration. In some cases, granular degeneration and fatty degeneration could be found in the liver and in some cases at a later stage of this disease the epithelial ceils of trachea and proventriculus might be found sioughed. In some cases at an early stage of this disease,cardiac hyperemia and hemorrhage could be observed.Esophaagus, pancreas and brain were found normal. Analysesand comparisons between the pathologic lesions of GVE and Gosling Plague (GP) were available in this paper as well.``characteristic could be as the data for NGVE diagnosis.

基因治疗中的腺病毒载体

通过对腺病毒的纤维蛋白、五邻体蛋白和六邻体蛋白的研究,改善了腺病毒载体对肿瘤细胞的靶向性。利用免疫抑制剂抑制、改造腺病毒壳粒蛋白的抗原表位或尽量减少腺病毒DNA中非必需基因的表达,减少了腺病毒载体的免疫反应。腺病毒载体在基因治疗中具有广泛的应用前景。

Adenovirus-mediated and tumor-specific transgene expression of the sodium-iodide symporter from the human telomerase reverse transcriptase promoter enhances killing of lung cancer cell line in vitro

Background The sodium-iodide symporter （NIS） protein can mediate the active radioiodine uptake.The human telomerase reverse transcriptase （hTERT） promoter is known to be selectively reactivated in majority of tumors and hence could be used for tumor targeting.We constructed a recombinant adenovirus containing the human sodium iodide symporter （hNIS） gene directed by the hTERT promoter, characterized the ability of infected cells in uptaking iodide, and explored the therapeutic efficacy of 131I in a lung cancer cell line in vitro.Methods The hTERT promoter was amplified by PCR from DNA isolated from log-phase HepG2 cells, subcloned into lineralized FL＊-hNIS/pcDNA3, and then the hTERT-hNIS sequence was subcloned into the shuttle plasmid pAdTrack.The recombinant adenovirus Ad-hTERT-hNIS was constructed by AdEasy system.A positive control adenovirusAd-CMV-hNIS and a negative control adenovirus Ad-CMV were created similarly.A549 cells were transduced with recombinant adenoviruses.125I uptake studies and sodium perchlorate suppression studies were used to confirm hNIS expression and function.Toxic effects of 131I on tumor cells were studied by in vitro clonogenic assay.Results We first successfully constructed an adenovirus mediated transgene expression system of the hNIS under the control of hTERT promoter.When infected with recombinant adenovirus constructs expressing hNIS directed by hTERTand CMV-promoters （Ad-hTERT-hNIS and Ad-CMV-hNIS, respectively）, the lung cancer cell line A549 had increased ability to uptake radioiodide up to 23- and 30- fold compared to the control parental cells, respectively.The radioiodide uptake ability of both the Ad-CMV-hNIS and Ad-hTERT-hNIS transduced cell lines were repressed 11-fold by sodium perchlorate （NaCIO4）.The subsequent in vitro clonogenic assay of the infected A549 cell line was further repressed to 23% （Ad-CMV-hNIS） and 30% （Ad-hTERT-hNIS） of the control group after receiving radioiodide for 7 hours （P 〈0.001）.Conclusion Our preliminary study indicates that an adenovirus mediated transgene expression system of the hNIS under the control of hTERT promoter has the potential to become an effective wide-spectrum yet highly specific anti-cancer strategy.