Effectiveness of direct needle puncture for complete hepaticojejunostomy anastomotic stricture after pancreaticoduodenectomy (with video).

A 79-year-old Japanese woman, who had undergone pancreaticoduodenectomy 6 months prior to presentation owing to pancreatic cancer, complained of jaundice with high fever. Computed tomography revealed proximal bile duct dilatation with complete hepaticojejunostomy anastomotic stricture (HJAS). We performed a single-balloon endoscopy for biliary drainage. The presence of a scar-like feature surrounding the anastomosis was identified as the HJAS. White-light imaging during single-balloon endoscopy revealed that the HJAS contained a milky whitish area (MWA), suggesting that a membranous and fibrosis layer affected continuous inflammation around the center of the anastomosis (within a scar-like feature). Endoscopic dilatation was performed using an endoscopic injection needle, with the MWA used as an indicator. A 23-gauge endoscopic injection needle was used to penetrate the center of the blind lumen within the MWA, and a pinhole was created in the stricture. After confirming the position of the proximal bile duct using a contrast medium with the needle, an endoscopic guidewire with a cannula was inserted into the pinhole. A through-the-scope sequential balloon dilator was used to dilate the stricture, and a plastic stent was inserted into the proximal bile duct. This endoscopic intervention led to positive outcomes. In cases of complete HJAS occlusion, an endoscopic approach to the bile duct is difficult because the anastomotic opening of the HJAS is not visible. Thus, puncturing within the MWA, which can be used as a scar-like landmark within a complete membranous HJAS, is considered a useful endoscopic strategy.

Unilateral drainage and chemotherapy prolong the patency of a plastic stent placed above the sphincter of Oddi in patients with malignant hilar biliary obstruction.

Objectives: To evaluate the results of inside stent therapy for unresectable malignant hilar biliary obstruction and identify factors related to stent patency duration. Methods: Of 44 patients who underwent initial inside-stent placement above the sphincter of Oddi from April 2017 to December 2022, 42 with the resolution of jaundice (clinical success rate, 95.5%) were retrospectively analyzed. Univariate and multivariate logistic regression analysis identified factors associated with stent patency duration. Results: Univariate analysis revealed significant differences in the drainage method (406 days for unilateral drainage vs. 305 days for bilateral drainage of the right and left liver lobes, p = 0.022) with or without chemotherapy (406 days with vs. 154 days without, p = 0.038). Multivariate analysis (Cox proportional hazards analysis) revealed similar results, with unilateral drainage (p = 0.031) and chemotherapy (p = 0.048) identified as independent factors associated with prolonged stent patency. Early adverse events were observed in two patients (4.8%; one cholangitis, one pancreatitis). Conclusions: Inside-stent therapy was safely performed in patients with malignant hilar biliary obstruction. Simple unilateral drainage and chemotherapy may prolong stent patency.

Environmental implications of dental restorative materials on the zebrafish Danio rerio: Are dental chair drainage systems an emerging environmental threat?

This study aimed to evaluate the environmental impact of dental materials: commercial composite Tetric EvoCeram®, glass ionomer Equia Forte® HT Fil, laboratory-prepared composite, alkasite Cention® Forte, amalgam Amalcap® Plus, and samples from dental chair drainage systems (DCDS). Methacrylate monomers were detected in the eluates of experimental and commercials composites, and alkasite. In DCDS samples solely mercury was found at concentrations of 0.08-1.86 µg/L. The experimental composite (48 h incubation) exhibited the highest toxicity on zebrafish Danio rerio (LC50=0.70 g/L), followed by amalgam (LC50=8.27 g/L) < Tetric EvoCeram® (LC50=10.94 g/L) < Equia Forte® HT Fil (LC50=24.84 g/L) < Cention® Forte (LC50=32.22 g/L). Exposure of zebrafish to DCDS samples resulted in decreased larval body length and increased occurrences of edema and blood accumulation. The results obtained highlight the need for additional monitoring and further research on the release of unreacted monomers and mercury from dental materials and their environmental impact.

Safety of one 8.5-Fr pigtail catheter for postoperative continuous open gravity drainage after uniportal video-assisted thoracoscopic surgery pneumonectomy.

OBJECTIVES: Uniportal video-assisted thoracoscopic surgery pneumonectomy (U-VATS-P) is feasible and safe from a perioperative standpoint. How to choose the proper chest tube and drainage method is important in enhanced recovery after surgery (ERAS) protocols. In this study, we aimed to assess the safety of one 8.5-Fr (1Fr = 0.333 mm) pigtail catheter for postoperative continuous open gravity drainage after U-VATS-P. METHODS: We retrospectively reviewed a single surgeon's experience with U-VATS-P for lung cancer from May 2016 to September 2022. Patients were managed with one 8.5-Fr pigtail catheter for postoperative continuous open gravity drainage after U-VATS-P. The clinical characteristics and perioperative outcomes of the patients were retrospectively analyzed. RESULTS: In total, 77 patients had one 8.5-Fr pigtail catheter placed for postoperative continuous open gravity drainage after U-VATS-P for lung cancer. The mean age was 60.9±7.39 (40-76) years; The mean FEV1 was 2.1±0.6 (l/s), and the mean FEV1% was 71.2±22.7. The median operative time was 191.38±59.32 min; the mean operative hemorrhage was 109.46±96.56 ml; the mean duration of postoperative chest tube drainage was 6.80±2.33 days; the mean drainage volumes in the first three days after operation were 186.31±50.97, 321.97±52.03, and 216.44±35.67 ml, respectively; and the mean postoperative hospital stay was 7.90±2.58 days. No patient experienced complications resulting from chest tube malfunction. Ten patients experienced minor complications. One patient with nonlife-threatening empyema and bronchopleural fistula required short rehospitalization for anti-inflammatory therapy and reintubation. Three patients with chylothorax were treated with intravenous nutrition. Four patients had atrial fibrillation that was controlled by antiarrhythmic therapy. Two patients had more thoracic hemorrhagic exudation after the operation, which was found in time and was cured effectively, so they were discharged from the hospital uneventfully after early hemostatic therapy and nutritional support. CONCLUSIONS: All patients in this study received early postoperative rehabilitation, and the rate of relevant complications was low. We therefore recommend a single 8.5-Fr pigtail catheter for postoperative continuous open gravity drainage as an effective, safe and reliable drainage method for the management of U-VATS-P.

Chemical characterization of green liquor dregs from 16 Swedish pulp and paper mills between 2017 and 2019.

Green liquor dregs (GLD) is an alkaline by-product from the pulp and paper industry with a pH between 10 and 14. Today most of the produced GLD in Sweden is landfilled. As a fine-grained alkaline material, it might be possible to use it for acid-generating mining waste remediation. To increase the utilization, quality characteristics and environmental performance need to be determined. In this study samples were collected 5 times from 16 mills during a period of 2.5 years, and were characterized by analyzing dry matter content, loss on ignition (LOI) 550 °C and LOI 950 °C, elemental analysis, pH, electrical conductivity, and calorific value. The results were then evaluated using multivariate statistics (PCA) as well as being compared to other studies and Swedish till. The results show that even if GLD is heterogenous (both within a mill and between different mills) trends can be seen for samples from most mills. When samples do stand out, it is predominately related to the same four mills. Most of the studied parameters showed characteristics favorable for use as a remediant; however, TOC, sulfur, and some of the elements require further study. In general, this study concludes that GLD can be a viable option for the remediation of small orphaned sulfidic mining sites and thus worthy of further studies on the interaction between GLD and acidic mining waste.Overall, GLD can be a good alternative for cost-effective remediation of smaller orphaned mining sites. It is readily available in large quantities, has the qualities needed for remediation of many orphaned acidic mining sites, and can often be locally sourced near the mining site. The use of GLD for mining site remediation is likely also a more sustainable method compared to traditional remediation methods.

Indigenous metal-tolerant mine water bacterial populations under varying metal stresses.

The present study investigated the indigenous metal-tolerant bacterial populations in the mine-water microbiome. Our intention was to assess the effects of the metal concentrations in mine water on the bacterial community of mine waters. The bacterial communities in Vanadium and Gold mine-water samples were exposed to different heavy-metal Arsenic, Cadmium, Chromium, Nickel, Mercury and Vanadium at two different concentrations (5 and 25 mM). The 16S rRNA amplicon from mine waters were sequenced using the Illumina's NGS MiSeq platform. Data analysis revealed a high diversity in the bacterial populations associated with the different heavy metals at different concentrations. The taxonomic profiles obtained after the exposure were different in different salts, but mostly dominated by Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Firmicutes at variable relative abundance. Principal Component Analysis (PCoA) predicts the clear community shift after exposure with heavy metals salts and emergence of tolerant community depending upon the specific community present in the original mine water.

Retropharyngeal abscess with mediastinal extension - A mausoleum of mumps: A case report.

Introduction: Retropharyngeal abscess is a fatal infection that is uncommon, yet serious, especially in young children below 5 years. Oropharyngeal infections, in particular, can cause it as a complication of upper respiratory infections. They can also lead to respiratory depression and acute upper airway blockage and other complications. Case presentation: The unusual case of large retropharyngeal abscess in a 2-year-old child, secondary to mumps infection who presented to us with impending airway compromise is reported. Discussion: Retropharyngeal abscess secondary to mumps is a rare occurrence.The child initially had a bilateral parotid enlargement with fever and upper respiratory tract infection, which was diagnosed clinically as mumps by primary care physician and later confirmed by IgM antibody testing. The child was initially treated conservatively as the symptoms were mild at the beginning, however, the child worsened progressively and presented o our institute with acute retropharyngeal abscess in stridor. Emergency tracheostomy and intraoral abscess drainage were done under general anesthesia followed by appropriate intravenous antibiotics therapy. Conclusion: A dramatic recovery was observed following the treatment approach. Although it is rare to see such a large RPA in this antibiotic era, it is imperative to maintain a high index of suspicion.

Combination of manual lymphatic drainage and Kinesio taping for treating pigmented villonodular synovitis: A case report.

BACKGROUND: Pigmented villonodular synovitis (PVNS) is a benign proliferative disorder that affects the synovial joints, bursae, and tendon sheaths. To date, few studies have reported on the treatment of postoperative pain and edema in patients with PVNS. Herein, we present the case of a woman who developed pain and edema in the left lower limb 1 wk after synovectomy and arthroscopic partial meniscectomy and was unable to walk due to limited flexion and extension of the left knee. CASE SUMMARY: A 32-year-old woman underwent synovectomy and arthroscopic partial meniscectomy successively and was treated with a combination of manual lymphatic drainage (MLD) and kinesio taping (KT) in our hospital to alleviate postoperative pain and edema. The following parameters were assessed at 2 wk post-treatment and 1 wk post-discharge follow up: suprapatellar circumference, infrapatellar circumference, visual analog scale score, knee range of motion, pittsburgh sleep quality index score, hamilton anxiety rating scale (HAMA) score, and hamilton depression rating scale (HAMD) score. After treatment, the postoperative pain and edema in the patient's left knee were effectively relieved, resulting in improved sleep quality and remarkably attenuated HAMA and HAMD scores. CONCLUSION: Combined MLD and KT may be an effective approach for relieving postoperative pain and edema in patients with PVNS.

Efficacy and safety analysis of continued nursing of complications in discharged patients after percutaneous transhepatic biliary drainage.

BACKGROUND: Percutaneous hepatobiliary drainage (PTCD) is an effective method for the treatment of biliary obstruction and other diseases, but postoperative complications are still one of the important problems faced by patients. Continuous nursing is a comprehensive nursing model that plays an important role in postoperative recovery. The purpose of this study was to investigate the effect of continuous nursing on the incidence of complications in patients after PTCD surgery through meta-analysis and to evaluate its efficacy and safety. AIM: To evaluate the effect of extended nursing on the incidence of complications in discharged patients after percutaneous transhepatic biliary drainage (PTBD). METHODS: Randomized controlled studies on PTBD postdischarge extended care were identified in the CNKI, Wanfang, VIP, CBM, PubMed, Cochrane Library, Embase, Web of Science, and other databases. The quality of the included studies was evaluated using the Joanna Briggs Institute of Australia literature quality evaluation tool, and a meta-analysis of the included studies was performed with RevMan 5.4 software. RESULTS: Finally, 9 studies were included, with a total sample size of 854 patients (425 patients in the control group and 429 patients in the intervention group). Meta-analysis revealed that extended care effectively reduced biliary tract infection (RR: 0.42, 95%CI: 0.30-0.57), puncture wound infection (RR: 0.19, 95%CI: 0.06-0.65), catheter protrusion or displacement in discharged patients after PTBD (RR: 0.31, 95%CI: 0.18-0.54), catheter blockage (RR: 0.23, 95%CI: 0.13-0.42), skin infection around the drainage tube (RR: 0.30, 95%CI: 0.12-0.77), and catheter-related readmissions (RR: 0.34, 95%CI: 0.18-0.65) (P < 0.05). CONCLUSION: Compared with conventional discharge care, extended care can effectively reduce the occurrence of complications such as biliary tract infection, puncture wound infection, catheter prolapse or displacement, catheter blockage, skin infection around the drainage tube, and catheter-related readmission in discharged patients after PTBD.

Retrograde Transvenous Thoracic Duct Embolization for Tubercular Chylothorax.

This case study documents the clinical profile of a 27-year-old male patient who visited the medical facility two months ago with complaints of dry cough, fatigue, weight loss, and occasional fever. He had been treated for ascites and pleural effusion in the hospital before presentation and returned with an intercostal drain in place. A detailed examination revealed symptoms of respiratory disorders, including fluid in both lungs, fever, and dyspnea. His fluid levels showed multiple deviations from the normal range, according to the report's findings and lab test results. It was determined that the patient had chylothorax, which resulted from hemophagocytic lymphohistiocytosis (HLH) and abdominal tubercular lymphadenopathy. His anti-tubercular treatment (AKT4) was initiated, along with octreotide for his management. Initial management included non-invasive ventilator (NIV) support, intravenous antibiotics, nebulization, and an intercostal chest drain (ICD). Later, the patient underwent retrograde transvenous thoracic duct embolization (TDE) using N-butyl cyanoacrylate (NBCA) glue. The removal of the drainage tube and the patient's stable discharge were made possible through regular monitoring and collaboration between specialists.

Case report: Inferior valved for non-valved glaucoma drainage device exchange for glaucoma control and cosmesis.

Introduction: While the exchange of a superior valved glaucoma drainage device (GDD) for a non-valved GDD has been reported for achieving glaucoma control, inferior GDD exchange for improving the cosmetic appearance of the eyes due to poor appearance caused by encapsulated GDDs has not been previously documented. Here, we report on two patients with inferior valved GDDs who underwent an exchange for non-valved devices for glaucoma control and cosmetic improvement. Case description: We report on the case of a 23-year-old gentleman and that of an 8-year-old girl, both of whom had inferior valved GDDs with uncontrolled intraocular pressure and unsightly appearance due to encapsulated GDD plates within the palpebral aperture. Both patients were unhappy about the appearance of their eyes. In each case, improvements in both glaucoma control and cosmesis were achieved by exchanging the valved GDDs for non-valved ones. Conclusion: Exchanging a valved for a non-valved GDD might help improve the cosmetic appearance of the eyes, in addition to providing glaucoma control.

Effect of Biliary Drainage on the Prognosis of Patients with Hepatocellular Carcinoma and Bile Duct Invasion.

Background/Aims: Bile duct invasion (BDI) is rarely observed in patients with advanced hepatocellular carcinoma (HCC), leading to hyperbilirubinemia. However, the efficacy of pretreatment biliary drainage for HCC patients with BDI and obstructive jaundice is currently unclear. Thus, the aim of this study was to assess the effect of biliary drainage on the prognosis of these patients. Methods: We retrospectively enrolled a total of 200 HCC patients with BDI from multicenter cohorts. Patients without obstructive jaundice (n=99) and those who did not undergo HCC treatment (n=37) were excluded from further analysis. Finally, 64 patients with obstructive jaundice (43 subjected to drainage and 21 not subjected to drainage) were included. Propensity score matching was then conducted. Results: The biliary drainage group showed longer overall survival (median 10.13 months vs 4.43 months, p=0.004) and progression-free survival durations (median 7.00 months vs 1.97 months, p<0.001) than the non-drainage group. Multivariate analysis showed that biliary drainage was a significantly favorable prognostic factor for overall survival (hazard ratio, 0.42; p=0.006) and progression-free survival (hazard ratio, 0.30; p<0.001). Furthermore, in the evaluation of first response after HCC treatment, biliary drainage was beneficial (p=0.005). Remarkably, the durations of overall survival (p=0.032) and progression-free survival (p=0.004) were similar after propensity score matching. Conclusions: Biliary drainage is an independent favorable prognostic factor for HCC patients with BDI and obstructive jaundice. Therefore, biliary drainage should be contemplated in the treatment of advanced HCC with BDI to improve survival outcomes.

Multicenter study comparing EUS-guided hepaticogastrostomy and ERCP for malignant biliary obstruction in patients with accessible papillae.

BACKGROUND: One advantage of endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is that it is difficult for reflux cholangitis, caused by duodenal pressure increasing due to duodenal obstruction, to occur. In addition, since stent deployment is performed away from the malignant stricture site, longer stent patency than with endoscopic retrograde cholangiopancreatography (ERCP) may be obtained. However, no study has previously compared EUS-HGS and ERCP for patients without duodenal obstruction or surgically altered anatomy. The aim of the present study was to compare clinical outcomes between EUS-HGS and ERCP in normal anatomy patients without duodenal obstruction. METHOD: In the ERCP group, patients who initially underwent biliary drainage were included. In the EUS-HGS group, patients who underwent EUS-HGS due to failed biliary cannulation were included. Patients with an inaccessible papilla, such as with surgically altered anatomy or duodenal obstruction, were excluded. RESULTS: A total of 314 patients who underwent ERCP and EUS-HGS were enrolled in this study. Of the 314 patients, 289 underwent biliary stenting under ERCP guidance, and 25 patients underwent biliary stenting under EUS-HGS. After propensity score-matching analysis, the adverse event rate tended to be lower in the EUS-HGS group than in the ERCP group. Although overall survival was not significantly different between the EUS-HGS and ERCP groups (p = .228), stent patency was significantly longer in the EUS-HGS group (median 366.0 days) than in the ERCP group (median 76.5 days). CONCLUSIONS: EUS-HGS had a lower adverse event rate, shorter procedure time, and longer stent patency than ERCP in cases of normal anatomy without duodenal obstruction.

Multi-decadal geochemical evolution of drainage from underground coal mines in the Appalachian basin, USA.

Coal mine drainage (CMD) in Appalachia is a widespread source of dissolved metals, SO4, and acidity that can degrade aquatic habitats and water supplies for decades following mine closure and flooding. In the bituminous coalfield of Pennsylvania, the Irwin Coal Basin (ICB) contains a series of partly to completely flooded, abandoned underground mines separated by leaky barriers within the Pittsburgh coal seam. CMD originated throughout the basin from minepool aquifers that formed after mine closures dating from 1910 to 1957. Historical and recent water quality data for eight CMD sites across the ICB, plus mineralogy and cation-exchange capacity of overburden lithologies, were analyzed to quantify important reactants and evaluate spatial and temporal water-quality trends. As overburden thickness and residence time increase along a ~ 50-km flowpath northeast to southwest in the basin, CMD becomes more alkaline, and Na concentrations increase. Since the 1970s, all eight ICB discharges have become less acidic, with exponential decreases in acidity, SO4, and Fe concentrations; only two CMD remain net-acidic (acidic pH at equilibrium). Exponential decay models that include a steady-state asymptote consistent with background groundwater chemistry and siderite equilibrium describe the early-stage, rapid contaminant concentration decay immediately after the "first flush" (initial flooding) and the progressive evolution toward late-stage background conditions. A geochemical evolution PHREEQC model indicates that spatial and temporal trends in pH, net-acidity, SO4, Fe, and major cations could be explained by the continuous dilution of first flush water by ambient groundwater combined with sustained water-mineral reactions involving pyrite and carbonates (calcite, dolomite, siderite) plus cation-exchange by clays (illite, chlorite, mixed-layer illite/smectite). These data and model results indicate that 1) cation-exchange reactions enhance calcite dissolution and alkalinity production, resulting in the evolution of CMD to Na-SO4-HCO3 type waters, and 2) siderite equilibrium could maintain dissolved Fe >16 mg/L over the next 40 years.

Patent conversion of a novel closed chest drainage device.

Closed chest drainage is typically necessary following Lobar and Sublobar resections to evacuate gases and fluids from the thoracic cavity, eliminate residual pleural space for lung expansion, and maintain negative pressure. Currently, three conventional closed chest drainage systems are commonly employed: single-chamber, double-chamber, and triple-chamber systems; each system has its own advantages and disadvantages. Despite the emergence of digital drainage systems in recent years, their high cost hinders their widespread adoption. Based on this premise, our research team has achieved a patent for a micro air pump-integrated chest closed drainage bottle, which has been further developed into a novel device integrating a three-chamber system with negative pressure control and power supply capabilities. This device enables patients undergoing perioperative lung procedures to ambulate freely while simultaneously receiving chest suction therapy-a concept that theoretically promotes rapid postoperative recovery. Moreover, this device offers economic benefits and holds potential for clinical implementation (particularly in economically underdeveloped regions). In this article, we modified the thoracic closed drainage device based on our patent and presented this novel thoracic closed drainage device after 3D printing and assembly.

Modified ventriculoperitoneal shunt applied to temporary external ventricular drainage.

External ventricular drainage (EVD) is a common procedure in neurosurgical practice. Presently, the three methods used most often include direct EVD (dEVD), long-tunneled external ventricular drains (LTEVDs), and EVD via the Ommaya reservoir (EVDvOR). But they possess drawbacks such as limited duration of retention, vulnerability to iatrogenic secondary infections, and challenges in regulating drainage flow. This study aimed to explore the use of a modified ventriculoperitoneal shunt (mVPS)-the abdominal end of the VPS device was placed externally-as a means of temporary EVD to address the aforementioned limitations. This retrospective cohort study, included 120 cases requiring EVD. dEVD was performed for 31 cases, EVDvOR for 54 cases (including 8 cases with previously performed dEVD), and mVPS for 35 cases (including 6 cases with previously performed EVDvOR). The one-time success rate (no need for further other EVD intervention) for dEVD, EVDvOR, and mVPS were 70.97%, 88.89%, and 91.42%, dEVD vs EVDvOR (P < 0.05), dEVD vs mVPS (P < 0.05), EVDvOR vs mVPS (P > 0.05). Puncture needle displacement or detachment was observed in nearly all cases of EVDvOR, while no such complications have been observed with mVPS. Apart from this complication, the incidence of postoperative complications was 35.48%, 14.81%, and 8.5%, dEVD vs EVDvOR (P < 0.05), dEVD vs mVPS (P < 0.05), EVDvOR vs mVPS (P > 0.05). Mean postoperative retention for EVD was 14.68 ± 9.50 days, 25.96 ± 15.14 days, and 82.43 ± 64.45 days, respectively (P < 0.001). In conclusion, mVPS significantly extends the duration of EVD, which is particularly beneficial for patients requiring long-term EVD.

Microbial community structure in an uranium-rich acid mine drainage site: implication for the biogeochemical release of uranium.

The generation of acid mine drainage (AMD) characterized by high acidity and elevated levels of toxic metals primarily results from the oxidation and dissolution of sulfide minerals facilitated by microbial catalysis. Although there has been significant research on microbial diversity and community composition in AMD, as well as the relationship between microbes and heavy metals, there remains a gap in understanding the microbial community structure in uranium-enriched AMD sites. In this paper, water samples with varying levels of uranium pollution were collected from an abandoned stone coal mine in Jiangxi Province, China during summer and winter, respectively. Geochemical and high-throughput sequencing analyses were conducted to characterize spatiotemporal variations in bacterial diversity and community composition along pollution groups. The results indicated that uranium was predominantly concentrated in the AMD of new pits with strong acid production capacity, reaching a peak concentration of 9,370 µg/L. This was accompanied by elevated acidity and concentrations of iron and total phosphorus, which were identified as significant drivers shaping the composition of bacterial communities, rather than fluctuations in seasonal conditions. In an extremely polluted environment (pH < 3), bacterial diversity was lowest, with a predominant presence of acidophilic iron-oxidizing bacteria (such as Ferrovum), and a portion of acidophilic heterotrophic bacteria synergistically coexisting. As pollution levels decreased, the microbial community gradually evolved to cohabitation of various pH-neutral heterotrophic species, ultimately reverting back to background level. The pH was the dominant factor determining biogeochemical release of uranium in AMD. Acidophilic and uranium-tolerant bacteria, including Ferrovum, Leptospirillum, Acidiphilium, and Metallibacterium, were identified as playing key roles in this process through mechanisms such as enhancing acid production rate and facilitating organic matter biodegradation.