温度对粘质沙雷菌蛋白质表达谱的影响

目的:研究粘质沙雷菌在不同温度下蛋白表达谱的差异,为探讨温度对生理特性和代谢产物的影响奠定基础.方法:采用双向电泳技术对25℃/37℃培养的粘质沙雷菌蛋白表达谱进行了比较和分析,差异蛋白点经过胶内酶切后进行MALDI-TOF质谱鉴定,所得到的肽指纹图谱用Mascot进行检索.结果与结论:共鉴定到31个差异点对应于23种蛋白.其中,S-腺苷甲硫氨酸合成酶的表达在37℃下调,给出了有关灵菌红素生物合成的新证据;此外,研究还发现,鲱精胺酶在37℃表达上调,提示粘质沙雷菌精氨酸代谢可能会随温度发生改变.     

Knee pain of rare etiology

A case of chronic knee pain of rare etiology is reported. Conventional radiographs excluded any articular pathology but ultrasound images showed features typical of a transsonic type tumor. Pathologic examination was necessary to establish the diagnosis, the tumor being an Antoni type A schwannoma.     

Hanging-delayed death (a rare phenomenon)

Hanging is one of the most common methods of suicide in India in which death of the individual occurs instantaneously. However, a few cases have been reported in literature in which death has occurred after a certain period of time or the patient has survived after prolonged resuscitative measures. A case of a 20-year-old female is described who survived for nine days after hanging, remaining unconscious throughout in the hospital. She died due to cerebral damage caused by cerebral anoxia.     

Molecular identification of the biowarfare simulant Serratia marcescens from a 50-year-old munition buried at Fort Detrick, Maryland

Serratia marcescens are Gram-negative bacteria that were often used by the U.S. military and others to track movement of bacteria in the environment. As part of ongoing construction at Fort Detrick, Maryland, what appeared to be a small bomblet was found buried in the ground at the site of an old test grid. A sample of a clear, straw-colored liquid was aseptically removed from the plastic reservoir; the results of routine cultures on standard bacteriological media were negative. DNA was extracted from the sample and found to be 99% identical to S. marcescens. These results demonstrate the ability to identify the contents of a biological munition that had been buried for approximately 50 years.     

MR imaging of large and rare pelvic masses from non-gynecological etiology

The diagnosis and characterization of pelvic masses may be problematic, especially when they are larger than 5 cm in diameter. The majority of large pelvic masses in women originate from gynecological structures. However, they may also originate from the GI tract, urinary tract, retroperitoneum, pelvic soft tissue structures, peritoneum and bones. MRI is the imaging modality of choice because it provides excellent contrast resolution and allows direct multiplanar imaging capabilities. Diagnosis is usually suggested after careful evaluation of the tumor location, anatomical relationships, morphology and signal characteristics. In this article, we will discuss the MR imaging features of large rare pelvic masses of non-gynecological origin, along with associated clinical and histological findings.     

A rare case of metastatic pancreatic adenocarcinoma presenting as a pulmonary embolism from nonbacterial thrombotic endocarditis

Nonbacterial thrombotic endocarditis (NBTE) also called, "Marantic endocarditis" occurs due to an underlying hypercoagulable state causing tissue damage and upregulation of the coagulation cascade, with noninfective vegetation formation on heart valves. Mitral and aortic valves are most commonly involved. NBTE is rare, with an incidence of 1.6%, with 65 cases identified during a 10-year autopsy analysis. The most common malignancies associated with NBTE include gynecological cancers, lung cancer, gastric cancer, and pancreatic cancers with adenocarcinoma histology being the greatest risk. Herein, we present a rare case of a 55-year-old male who presented with acute hypoxic respiratory failure secondary to pulmonary embolism due to nonbacterial thrombotic endocarditis. He was found to have advanced pancreatic adenocarcinoma on further investigation of the 2.2 cm hypodense cystic mass in the distal pancreatic body and tail, and complex liver masses which were incidentally found on computed tomography angiography (CTA) of the chest. This is a rare phenomenon and clinicians have to consider the hypercoagulable state associated with cancers, particularly pancreatic adenocarcinoma, and the risk of NBTE.     

Fatal methemoglobinemia complicating alkaptonuria (ochronosis): a rare presentation

A 61-year-old female died in hospital with multiple organ failure 4 weeks following presentation with acute kidney injury, hemolytic anemia and methemoglobinemia. At autopsy, brown to black discoloration of cartilages was observed. Histology revealed brown pigmentation of the hyaline cartilage, with focal full-thickness erosion of the articular hyaline cartilage, characteristic of alkaptonuria (ochronosis). Although alkaptonuria is rarely fatal, this case illustrates a rare acute fatal complication. Accumulation of circulating homgentisic acid secondary to acute derangement of renal function is believed to have overwhelmed the endogenous antioxidant processes, resulting in hemolysis and methemoglobinemia, which were refractory to treatment. Small numbers of cases have previously been reported in the literature in patients known to suffer with the disease, all of which were preceded by acute kidney injury. Whilst the clinical diagnosis of alkaptonuria may be challenging, the autopsy findings of this rare condition are striking and this case illustrates the utility of the autopsy, albeit retrospectively, in arriving at a diagnosis. To our knowledge this is the first reported case where previously undiagnosed alkaptonuria has presented with methemoglobinemia.