[Anatomical classification of and laparoscopic surgery for left-sided colorectal cancer with persistent descending mesocolon].

Objective: To investigate anatomical morphology and classification of persistent descending mesocolon (PDM) in patients with left-sided colorectal cancer, as well as the safety of laparoscopic radical surgery for these patients. Methods: This is a descriptive study of case series. Relevant clinical data of 995 patients with left colon and rectal cancer who had undergone radical surgery in Fujian Medical University Union Hospital from July 2021 to September 2022 were extracted from the colorectal surgery database of our institution and retrospectively analyzed. Twenty-four (2.4%) were identified as PDM and their imaging data and intra-operative videos were reviewed. We determined the distribution and morphology of the descending colon and mesocolon, and evaluated the feasibility and complications of laparoscopic surgery. We classified PDM according to its anatomical characteristics as follows: Type 0: PDM combined with malrotation of the midgut or persistent ascending mesocolon; Type 1: unfixed mesocolon at the junction between transverse and descending colon; Type 2: PDM with descending colon shifted medially (Type 2A) or to the right side (Type 2B) of the abdominal aorta at the level of the origin of the inferior mesentery artery (IMA); and Type 3: the mesocolon of the descending-sigmoid junction unfixed and the descending colon shifted medially and caudally to the origin of IMA. Results: The diagnosis of PDM was determined based on preoperative imaging findings in 9 of the 24 patients (37.5%) with left-sided colorectal cancer, while the remaining diagnoses were made during intraoperative assessment. Among 24 patients, 22 were male and 2 were female. The mean age was (63±9) years. We classified PDM as follows: Type 0 accounted for 4.2% (1/24); Type 1 for 8.3% (2/24); Types 2A and 2B for 37.5% (9/24) and 25.0% (6/24), respectively; and Type 3 accounted for 25.0% (6/24). All patients with PDM had adhesions of the mesocolon that required adhesiolysis. Additionally, 20 (83.3%) of them had adhesions between the mesentery of the ileum and colon. Twelve patients (50.0%) required mobilization of the splenic flexure. The inferior mesenteric artery branches had a common trunk in 14 patients (58.3%). Twenty-four patients underwent D3 surgery without conversion to laparotomy; the origin of the IMA being preserved in 22 (91.7%) of them. Proximal colon ischemia occurred intraoperatively in two patients (8.3%) who had undergone high ligation at the origin of the IMA. One of these patients had a juxta-anal low rectal cancer and underwent intersphincteric abdominoperineal resection because of poor preoperative anal function. Laparoscopic subtotal colectomy was considered necessary for the other patient. The duration of surgery was (260±100) minutes and the median estimated blood loss was 50 (20-200) mL. The median number of No. 253 lymph nodes harvested was 3 (0-20), and one patient (4.2%) had No.253 nodal metastases. The median postoperative hospital stay was 8 (4-23) days, and the incidence of complications 16.7% (4/24). There were no instances of postoperative colon ischemia or necrosis observed. One patient (4.2%) with stage IIA rectal cancer developed Grade B (Clavien-Dindo III) anastomotic leak and underwent elective ileostomy. The other complications were Grade I-II. Conclusions: PDM is frequently associated with mesenteric adhesions. Our proposed classification can assist surgeons in identifying the descending colon and mesocolon during adhesion lysis in laparoscopic surgery. It is crucial to protect the colorectal blood supply at the resection margin to minimize the need for unplanned extended colectomy, the Hartmann procedure, or permanent stomas.

[Lung transplantation in patients with paraquat poisoning: a case report and literature review].

Objective: To analyze 8 cases of paraquat lung transplantation in the world, and to explore the timing of lung transplantation and the factors affecting prognosis. Methods: An analysis of the clinical data of a paraquat poisoning lung transplant patient completed by The 12th People's Hospital of Guangzhou Medical University and The First People's Hospital affiliated to Guangzhou Medical University in August 2017 and literature review. Results: A 26 years old female patient was admitted to the hospital ingested 20% paraquat solution 20ml. On the 58th day of poisoning, she underwent double lung transplantation under general anesthesia. The operation was successful. Excised lungs show extensive lung fibrosis in both lungs, which was consistent with paraquat poisoning. Used tacrolimus and corticosteroids and mycophenolate antirejection, the patient discharged 46 days after surgery. 7 articles were retrieved through the search tool, and a total of 8 articles included this case were reported. Five patients who underwent lung transplantation within 1 month after poisoning all died, And 3 patients conducted lung transplantation for more than 1 month after poisoning survived; Pathogenic bacteria were isolated from the sputum in 3 of the 8 cases, all containing Pseudomonas, 2 of which died, and our case survived. Conclusion: Appropriate transplantation time window is very important for the prognosis of paraquat poisoning after lung transplantation. Active treatment of the sputum pathogens, improving the donor receptor matching, and exhausting the various means to remove the paraquat from the storage pool which may improve success rate of lung transplantation.

Second-harmonic imaging microscopy for identifying colorectal intraepithelial neoplasia.

In this study, second-harmonic imaging microscopy was used to monitor precancerous colorectal lesions at different stages. It was found that the morphology of glands and lamina propria in mucosa changes with the progression of colorectal diseases from normal to low-grade intraepithelial neoplasia to high-grade intraepithelial neoplasia and this microscopy has the ability of direct visualization of these warning symptoms. Furthermore, two morphologic variables were quantified to determine the changes of glands and collagen in lamina propria during the development of colorectal intraepithelial neoplasia. These results suggest that second-harmonic imaging microscopy has the potential in label-freely and effectively distinguishing between normal and precancerous colorectal tissues, and will be helpful for early diagnosis and treatment of colorectal diseases.

[Prognostic factors of postoperative incisional surgical site infections for colorectal cancer].

Objective: To explore the prognostic factors of postoperative incisional surgical site infections (I-SSI) for colorectal cancer. Methods: Clinical data of 2 385 colorectal cancer patients undergoing resection by the same surgical team in Department of Colon and Rectum Surgery, Fujian Medical University Union Hospital from January 2000 to February 2014 was analyzed retrospectively. There were 1 421 male and 964 female patients, with a mean age of (59±13) years. Univariate analysis and multivariate Logistic regression analysis were performed for independent prognostic factors of I-SSI. Results: The I-SSI occurred in 77 patients (3.23%). The results of univariate analysis showed that there were statistical differences in body mass index (t=-3.356), operation time (t=-3.609), length of incision (t=-5.492), radical operation (χ2=8.963), laparoscopic surgery (χ2=25.884), combined evisceration (χ2=6.349) and intraoperative blood infusion (χ2=4.176) between two groups (all P<0.05) . The results of multivariate Logistic regression analysis showed that independent prognostic factors of I-SSI were identified to be body mass index (OR=1.087, 95%CI: 1.023 to 1.155, P=0.007), operation time (OR=1.007, 95%CI: 1.002 to 1.012, P=0.006), preoperative chemoradiotherapy (OR=2.434, 95%CI: 1.099 to 5.393, P=0.028) and combined evisceration (OR=2.596, 95%CI: 1.060 to 6.357, P=0.037). The independent protective prognostic factor of I-SSI was identified to be the laparoscopic surgery (OR=0.386, 95%CI: 0.170 to 0.877, P=0.023). Conclusions: Body mass index, operation time, preoperative chemoradiotherapy and combined evisceration are identified to be independent prognostic factors for I-SSI. High-risk patients should receive individualized perioperative intervention. Nevertheless, the laparoscopic surgery can decrease the incidence of I-SSI.

Engineering and functional evaluation of a single-chain antibody against HIV-1 external glycoprotein gp120.

The HIV-1 envelope glycoprotein surface subunit gp120 is an attractive target for molecular intervention. This is because anti-HIV-1 gp120 neutralizing antibodies display the potential ability to inhibit HIV-1 infection. The present investigation describes the construction of a genetically engineered single chain antibody (scFv102) against HIV-1 gp120, its expression and functional evaluation. The parental hybridoma cell line (102) produces an immunoglobulin directed against the conserved CD4-binding region of gp120. cDNAs encoding the variable regions of the heavy (V(H)) and light (V(L)) chains were prepared by reverse transcription PCR and linked together with an oligonucleotide encoding a linker peptide (Gly(4)Ser)(3) to produce a single chain antibody gene. The resulting DNA construct was cloned into a prokaryotic expression vector (pET28) and recombinant scFv102 was expressed in Eserichia coli as an insoluble protein. The denatured scFv102 was refolded and purified by immobilized metal ion affinity chromatography. Purified scFv102 had the same specificity as the intact IgG in immuno-blotting assays and immuno-fluorescence (IF) detection, but ELISA analyses demonstrated the affinity of scFv102 to be 5-fold lower than that of the parental monoclonal antibody. In neutralization assays, scFv102 at concentrations lower than 40 microg/ml exhibited efficient interference with viral replication and inhibition of viral infection (90%) across a range of primary isolates of subtype B HIV-1. These results suggest that the constructed anti-HIV-1 gp120 scFv102 has good biological activity and can potentially be used for in vitro diagnostic and in vivo therapeutic applications.

Cloning and expression of the external-glycoprotein gene mutant from HIV-2 in the methylotrophic yeast Pichia pastoris and identification of the glycoprotein.

To achieve high-level expression of HIV-2(ROD) external glycoprotein gp105 in Pichia pastoris, the gp105 gene mutant tP1, with the 5' non-functional region of the gp105 gene removed, was obtained by PCR amplification and was cloned into secreted expression vector pHILS1. The His(+)Mut(s) recombinant P. pastoris strain was screened by PCR and induced by methanol. SDS/PAGE and Western-blot analyses showed that mutation of the low-usage codon AGG into synonymous codon CGA and the introduction of the optimal codon TTC made P. pastoris overexpress tP1, an 85 kDa heterologous glycoprotein that was secreted into the medium and recognized specifically by HIV-2 polyclonal antibody. The recombinant strain GS115/tP1 had excellent genetic stability in terms of the properties of growth and expression of gp105, and seven out of 58 recombinant stains with a yield of 29% were selected to be used for further purification of gp105.

The epidemiology of lung cancer in Xuan Wei, China: current progress, issues, and research strategies.

In Xuan Wei, a rural Chinese county of about one million people, females' annual lung cancer mortality is China's highest, and males' is among China's highest. Xuan Wei's very high indoor air pollution levels (sometimes exceeding 20 mg/m3), residentially stable population, relatively uncomplicated lifestyle, and wide geographic variation in lung cancer mortality render it highly amenable to quantitative, interdisciplinary investigation of chemical carcinogens due to indoor air pollution. To date, epidemiologic findings reveal a closer association of lung cancer with the indoor burning of "smoky" coal (as opposed to "smokeless" coal or wood) than with tobacco use or occupation. Current aerometric, chemical, and toxicologic findings tend to confirm this association, though the specific carcinogenic constituents of Xuan Wei indoor air pollution have not yet been determined. Chinese and American investigators are conducting interdisciplinary field and laboratory investigations to quantify the lung cancer risk attendant on indoor air pollution relative to other factors, to measure and compare the characteristics of pollution from different Xuan Wei fuels, to determine the relative etiologic importance of pollution composition and concentration, and to develop quantitative relationships between air pollution dose and lung cancer risk.

Lung cancer and indoor air pollution in Xuan Wei, China.

In Xuan Wei County, Yunnan Province, lung cancer mortality is among China's highest and, especially in females, is more closely associated with indoor burning of "smoky" coal, as opposed to wood or "smokeless" coal, than with tobacco smoking. Indoor air samples were collected during the burning of all three fuels. In contrast to wood and smokeless coal emissions, smoky coal emission has high concentrations of submicron particles containing mutagenic organics, especially in aromatic and polar fractions. These studies suggested an etiologic link between domestic smoky coal burning and lung cancer in Xuan Wei.