Disturbance of cell-size determination by forced overproduction of sulfoquinovosyl diacylglycerol in the cyanobacterium Synechococcus elongatus PCC 7942.

Sulfoquinovosyl diacylglycerol (SQDG) is present in the membranes of cyanobacteria or their descendants, plastids at species-dependent levels. We investigated the physiological significance of the intrinsic SQDG content in the cyanobacterium Synechococcus elongatus PCC 7942, with the use of its mutant, in which the genes for SQDG synthesis, sqdB and sqdX, were overexpressed. The mutant showed a 1.3-fold higher content of SQDG (23.6 mol% relative to total cellular lipids, cf., 17.1 mol% in the control strain) with much less remarkable effects on the other lipid classes. Simultaneously observed were 1.6- to 1.9-fold enhanced mRNA levels for the genes responsible for the synthesis of the lipids other than SQDG, as if to compensate for the SQDG overproduction. Meanwhile, the mutant showed no injury to cell growth, however, cell length was increased (6.1 ± 2.3, cf., 3.8 ± 0.8 µm in the control strain). Accordingly with this, a wide range of genes responsible for cell division were 1.6-2.4-fold more highly expressed in the mutant. These results suggested that a regulatory mechanism for lipid homeostasis functions in the mutant, and that SQDG has to be kept from surpassing the intrinsic content in S. elongatus for repression of the abnormal expression of cell division-related genes and, inevitably, for normal cell division.

Jejunogastric intussusception after pancreaticoduodenectomy: a case report.

BACKGROUND: Jejunogastric intussusception (JGI) is a rare, but potentially fatal complication that can occur following gastric surgery, and the reported incidence of JGI is as low as 0.1%. Early diagnosis and treatment are critical for JGI to prevent major complications such as bowel necrosis and death. Although emergency surgery is the standard treatment, endoscopic reduction has also been reported to be effective in JGI patients without bowel necrosis. Several early recurrent cases treated with surgical or endoscopic reduction have been reported. We report an extremely rare case of JGI after pancreaticoduodenectomy (PD) using Child's procedure that was successfully treated with surgical reduction and fixation. CASE PRESENTATION: An 81-year-old man who had undergone PD using Child's procedure 3 years ago presented to our hospital with epigastric pain and nausea. His vital signs were stable, and abdominal examination revealed mild tenderness with a palpable mass in the mid-epigastrium. Abdominal computed tomography (CT) and gastroscopy revealed a JGI of the efferent loop, and exploratory laparotomy was immediately performed. During the operation, the efferent loop showed no adhesions and was intussuscepted through the gastrojejunostomy into the gastric lumen. An incision in the anterior wall of the stomach revealed no evidence of ischemia of the intussusceptum. The efferent loop was reduced using Hutchinson's maneuver and fixed to the afferent loop to prevent a recurrence. The postoperative course was uneventful, and there was no sign of recurrence 12 months postoperatively. CONCLUSIONS: JGI after PD is an extremely rare, but has severe complications. Surgery might be the optimal treatment for JGI in terms of preventing recurrence, even in cases without bowel necrosis.

Sedation outcomes for remimazolam, a new benzodiazepine.

Remimazolam is a new ultrashort-acting benzodiazepine with fast onset, quick recovery, and few side effects, such as hypotension and respiratory depression. It is expected to be safe and effective for a wide range of patients undergoing intravenous sedation for dental procedures. The aim of this literature review was to evaluate clinical and sedation outcomes for remimazolam, including method of administration, level of sedation at the dose required, and clinical adverse events. An electronic literature search of databases was conducted, and eight articles were selected for inclusion in this review. Onset time from drug administration to optimal sedation level was faster for remimazolam (around 1.5-6.4 min) than for midazolam. Recovery time was significantly shorter for remimazolam than for midazolam and propofol. A study comparing various doses of remimazolam with midazolam found no significant difference in safety. Comparison of a remimazolam group with a propofol group showed that incidences of hypotension (13.0% vs 42.9%, respectively) and respiratory depression (1.1% vs 6.9%, respectively) were significantly lower for remimazolam. Remimazolam appears to be an ideal sedative.

Laparoscopic surgery for sigmoid colon cancer with complicated communication between the superior and inferior mesenteric arteries.

To perform complete mesocolic excision with central vessel ligation, it is important to recognize the vessel anomaly and the location of the tumor. For left-sided colon cancer, the variations in the course of the left colic artery and accessary middle colic artery must be recognized preoperatively. Here, we describe our experience with a 57-year-old man who was diagnosed with sigmoid colon cancer with complicated inter-mesenteric connections between the inferior mesenteric artery (IMA) and superior mesenteric artery (SMA), possibly due to median arcuate ligament syndrome. We performed laparoscopic sigmoidectomy with low ligation of the IMA to preserve the extremely enlarged left colic artery. The total operative time was 155 minutes, and the estimated total blood loss was 10 mL. The patient was discharged on postoperative day 9 without any postoperative complications. For patients with vascular anomalies in the left-sided mesocolon, preoperatively ruling out SMA stenosis by using angiography and 3-D CT might be important.

Aspiration of periodontopathic bacteria due to poor oral hygiene potentially contributes to the aggravation of COVID-19.

Coronavirus infectious disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was declared a pandemic in March 2020 by the World Health Organization. Periodontitis, one of the most prevalent diseases worldwide, leads to alveolar bone destruction and subsequent tooth loss, and develops due to pro-inflammatory cytokine production induced by periodontopathic bacteria. Periodontopathic bacteria are involved in respiratory diseases, including aspiration pneumonia and chronic obstructive pulmonary disease (COPD), and other systemic diseases, such as diabetes and cardiovascular disease. Patients with these diseases have an increased COVID-19 aggravation rate and mortality. Because aspiration of periodontopathic bacteria induces the expression of angiotensin-converting enzyme 2, a receptor for SARS-CoV-2, and production of inflammatory cytokines in the lower respiratory tract, poor oral hygiene can lead to COVID-19 aggravation. Conversely, oral care, including periodontal treatment, prevents the onset of pneumonia and influenza and the exacerbation of COPD. The reduced chance of receiving professional oral care owing to long-term hospitalization of patients with COVID-19 may increase the aggravation risk of infection in the lower respiratory tract. It can be hypothesized that periodontopathic bacteria are involved in the COVID-19 aggravation and therefore, the management of good oral hygiene potentially contributes to its prevention.

Saliva-based PCR tests for SARS-CoV-2 detection.

The outbreak of novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide. Nasopharyngeal swabs are widely used in polymerase chain reaction (PCR) test to detect SARS-CoV-2. However, the collection of nasopharyngeal swabs has a series of drawbacks concerning exposure of healthcare staff, difficulty in collection, and discomfort of patients. Therefore, an alternative noninvasive sample for diagnostic of emerging viral diseases is required. The usefulness of saliva screening tests is compared to conventional swab tests in this report. The results suggest that saliva could be a reliable sample for detecting SARS-CoV-2.

Argon plasma coagulation for successful treatment of bile leakage after subtotal cholecystectomy.

BACKGROUND: Subtotal cholecystectomy is an effective surgical method to decrease the risk of complications for gallbladders that are difficult to remove. However, there is a risk for postoperative refractory bile leakage through the gallbladder stump. Here, we report a new management technique involving the use of argon plasma coagulation (APC) to stop bile leakage after a subtotal cholecystectomy. CASE PRESENTATION: A 74-year-old man was referred to our hospital for abdominal pain and fever. Contrast-enhanced computed tomography of the abdomen showed fluid collection, such as an abscess, surrounding the gallbladder and hepatic flexure colon. The patient was diagnosed with colonic perforative peritonitis, and he underwent emergency surgery. On laparotomy, the abscess was observed outside of the hepatic flexure colon and gallbladder necrosis was detected. The neck of the gallbladder and the area close to the hepatoduodenal ligament was severely inflamed prohibiting dissection. The hepatic flexure colon was part of the abscess wall, and resection was needed. A subtotal cholecystectomy and right hemicolectomy confirmed peritonitis caused by cholecystic perforation. The mucous membrane of the gallbladder neck that remained was necrotic or detached. Therefore, the stump of the gallbladder was closed by primary sutures without cauterization of the mucosa. On postoperative day 6, bile leakage from the gallbladder stump was revealed. Percutaneous and endoscopic retrograde cholangiography drainage were performed. However, the liquid, which seemed to be secreted from the mucosa of the remnant gallbladder, was continuously obtained. We used APC to cauterize the gallbladder mucosa through the fistula of the abdominal drainage tube. Bile leakage and mucus discharge were improved after three rounds of APC cauterization. CONCLUSIONS: APC effectively treated refractory bile leakage from a gallbladder stump after subtotal cholecystectomy for severe cholecystitis.

Cranial-first approach of laparoscopic left colectomy for T4 descending colon cancer invading the Gerota's fascia.

BACKGROUND: The safety and feasibility of laparoscopic colectomy for T4 colorectal cancer remain controversial. We believe that setting a "Goal" that will guide the surgeons in returning from the deep layer could be the key to safe en bloc resection of neighboring organs. For descending colon cancer, the cranial-first approach makes it possible to clearly visualize the pancreas and origin of the transverse mesocolon, leading to safe splenic flexure mobilization and complete mesocolic excision, which is the strongest advantage of this approach. CASE PRESENTATION: A 75-year-old woman was diagnosed with T4 descending colon cancer invading the Gerota's fascia. We performed laparoscopic left colectomy using the cranial-first approach to set a "Goal" at the inferior border of the pancreas for safe resection of the Gerota's fascia. The total operative time was 233 min, and the estimated blood loss was 98 ml. She was discharged after surgery without postoperative complications. Pathological findings revealed the invasion into the Gerota's fascia, and the resection margin was negative for cancer. CONCLUSIONS: The cranial-first approach of laparoscopic left colectomy appears to be safe and feasible and could be a promising method for selected patients with T4 descending colon cancer invading the Gerota's fascia.

Complete Resection without Any Ostomies by Laparoscopic Extended Surgery for Locally Advanced T4 Sigmoid Colon Cancer Invading the Urinary Bladder and Ureter.

The feasibility and safety of laparoscopic surgery for locally advanced colorectal cancer remain controversial due to the high rate of incomplete resection and conversion to open surgery. Especially for T4 colorectal cancer, laparoscopic techniques are still demanding mainly because of the difficulty in distinguishing between inflammation and tumor involvement, which often lead surgeons to do overtreatment in surgery. We believe laparoscopic magnified and multidirectional approach might be useful for pathologically complete resection and minimizing an unnecessary extended surgery for these cases. A 49-year-old man was diagnosed with locally advanced T4 sigmoid colon cancer invading the urinary bladder and ureter. We performed laparoscopic anterior resection with en bloc resection of the urinary bladder and the left ureter. Total operative time was 462 min, and the estimated blood loss was 50 ml. This patient was discharged on the 28th day after surgery without any ostomies and urinary functional disorders. The magnified view by laparoscopic techniques from multiple directions would enable surgeons to set surgical landmarks for another approach, which is the key for safe and feasible laparoscopic surgery in patients with locally advanced T4 colorectal cancer.