Progress in research of liver injury induced by acute biliary pancreatitis

Acute biliary pancreatitis (ABP) not only causes acute inflammation of the pancreas, but also leads to obstruction or infection of the biliary system. Liver injury is one of the most common complications of ABP. The pathological mechanisms mainly include infection and endotoxin, cholestasis, pancreatic enzyme damage, microcirculatory disorders, and oxidative stress, and the research conclusions are mostly derived from animal experiments. On the basis of routine medical treatment of ABP, active anti-infective treatment and rapid relief of biliary obstruction can promote the recovery of ABP-related liver injury.

[Initiation, development, and achievements of burn rehabilitation therapy in China]

Burn rehabilitation in China started from compression therapy in the mid-1970s, which showed the dual effects of prevention and treatment of hypertrophic scars. It not only promoted functional rehabilitation but also strengthened the confidence of patients in rehabilitation treatment. Thereafter, more therapies were brought into practice, such as intra-scar injection of triamcinolone acetonide, application of plastic splints, hydrotherapy, exercises with equipment, skin care, local therapeutic massage, active and passive exercises, as well as external use of drugs for inhibiting scars and pigments. Since the beginning of the 21st century, rehabilitation therapies have been gradually increasing. Psychological rehabilitation, occupational therapy, external use of silicone gel, wax therapy and sound, light, electricity, and radiation therapy have been carried out. Many hospitals have established foundations and held summer camps for children. As far as the whole country is concerned, compared with the huge demand, we still face a number of problems such as shortage of working staff, limited working space, capital chain rupture, lack of multi-disciplinary cooperation, untimely treatment, and incomplete rehabilitation. Nowadays, with increasing knowledge of burn rehabilitation and number of practitioners, improvement of equipment and economic situation, the pace of rehabilitation has accelerated, and the overall implementation of burn rehabilitation therapy has shown great vitality. Patients with burn injury involving over 80% total burn surface area (TBSA) of total burn area or full-thickness burn over 60% TBSA were cured and recovered in different levels of hospitals nationwide, which not only reflects the superb level of burn treatment in China but also reflects the overall improvement of rehabilitation level of the country.

Treatment of irritable bowel syndrome with neurotransmitter mediators

Irritable bowel syndrome (IBS), characterized by chronically recurring abdominal pain or discomfort and altered bowel habits and/or stool characters, is a chronic functional gastrointestinal disorder. Patients with IBS are more likely to suffer from coexistent mood disorder, depression, anxiety, and neuroticism. The mechanism of IBS may be related to such factors as abnormal intestinal motility, visceral hypersensitivity, disorder of brain-gut interactions, psychological disturbance and so on. General measures, such as antispasmodics, prokinetic agents, antidiarrheal agents, cathartic agent, and antidepressants are essential for effective IBS management. Anticholinergic agents and monoamine neurotransmitters, including their receptor agonists and antagonists, are all effective treatments for IBS; low-dose therapy can not only mitigate gastrointestinal motility, spasmolysis, and analgesia but also reduce psychological symptoms including anxiety and depression and improve the quality of life. Further larger-scale, long-term, randomized controlled clinical trials are warranted to confirm therapeutic effect and safety of neurotransmitter mediators for treatment of IBS.

Effects of vacuum sealing drainage on the treatment of cranial bone-exposed wounds in rabbits

This study was designed to assess the efficacy of vacuum sealing drainage (VSD) on skull exposure wounds in rabbits and to investigate the underlying mechanism of the process. Full-thickness excisional circular wounds 2×2 cm with or without periosteum involvement were created in 88 New Zealand white rabbits (mean body weight: 3.0±0.65 kg). Animals were randomly divided into 4 groups: periosteum-intact wounds treated with traditional dressing (p+control), periosteum-intact wounds treated with VSD (p+VSD), periosteum-lacking wounds treated with traditional dressing (p–control) and periosteum-lacking wounds treated with VSD (p–VSD). The wounds treated with traditional dressing were covered with Vaseline gauze, while VSD treatment was accompanied with continuous –120 mmHg pressure. Finally, wound tissues were harvested for analysis of hydroxyproline content and histologic detection. VSD hastened the wound healing process significantly (P<0.05) compared to the corresponding control groups. VSD alleviated the inflammation reaction, accelerated re-epithelialization and facilitated the organization of collagen fibers into neat rows. During the wound healing process, the hydroxyproline content increased overtime [i.e., postoperative days (POD) 7, POD 10 and POD 15] in all four groups, and it peaked in the p+VSD group. VSD also promoted angiogenesis via increasing number and quality of collagen. We concluded that VSD can promote healing in bone-exposed wounds via increasing hydroxyproline content and vessel density, reducing inflammatory responses and generating ordered collagen arrangement.

Bone marrow-derived mesenchymal stem cell transplantation ameliorates oxidative stress and restores intestinal mucosal permeability in chemically induced colitis in mice

BACKGROUND

Ulcerative colitis (UC) can be viewed as an autoimmune disease. Bone marrow-derived mesenchymal stem cells (MSCs) with its regenerative, cellular multi-lineage and immunomodulatory abilities can influence the repair of damaged tissues in UC. This study investigated the effects of MSCs transplantation on the mice intestinal barrier in response to oxidative stress injury.

METHODS

Colitis was induced by daily consecutive administration of 5% dextran sulfate sodium (DSS) solution for 7 days. Male murine MSCs were isolated and transplanted into female mice via injection in the tail vein. Serum and colon specimens were collected at 12 h, 24 h, 3 d, 7 d and 14 d after injection. Serum levels of D-lactate (D-LAC), diamine oxidase (DAO), colonic levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were quantified. The SRY protein of the male sex determinant gene expression and E-cadherin were also ascertained intracellularly.

RESULTS

Three days after receiving male MSCs transplantation, SRY protein expression was detected. The quantity increased on successive days. Serum levels of D-LAC and DAO, colonic MDA and SOD normalized in a shorter time period compared to controls (p<0.05). Not surprisingly, histological regeneration of tissue and E-cadherin expression in the colon of MSCs transplanted mice also occurred in a shorter time period than controls.

CONCLUSIONS

Transplanted MSCs restored mucosal permeability, and minimized oxidative stress related injury.

Production and characterization of monoclonal antibodies to porcine brain pyridoxal kinase

Six monoclonal antibodies that recognize porcine brain pyridoxal kinase have been selected and designated as PK67, PK86, PK91, PK144, PK252 and PK275. A total of six monoclonal antibodies recognizing different epitopes of the enzyme were obtained, of which four inhibited the enzyme activity. When total proteins of porcine brain homogenate separated by SDS-PAGE were subjected to monoclonal antibodies, a single reactive protein band of molecular weight 39 kDa which comigrated with purified porcine pyridoxal kinase was detected. Using the anti-pyridoxal kinase antibodies as probes, the cross reactivities of brain pyridoxal kinase from human and other mammalian tissues and from avian sources were also investigated. Among human and all animal tissues tested, immunoreactive bands on Western blots appeared to have the same molecular mass of 39 kDa. These results indicate that mammalian brains contain only one major type of immunologically similar pyridoxal kinase, although some properties of the enzymes reported previously differed from one another.

Antigenic difference between viral strains causing classical and mild types of epidemic hemorrhagic fever with renal syndrome in China

The antigenic relationship between viral isolates from Apodemus and Rattus that appear to cause the classical and mild types of epidemic hemorrhagic fever (EHF) in China was studied by cross-immunofluorescence, cross-neutralization, immunofluorescence blocking tests, and cross-enzyme-linked immunosorbent assay (ELISA). Obvious antigenic diversity between the isolates was demonstrated by cross-neutralization, immunofluorescence blocking tests, and cross-ELISA. Antisera from patients with classical EHF neutralized viruses of both types to a similar degree, but antisera from patients with mild EHF showed little neutralization of apodemus virus. Similarly, antisera from classical EHF blocked immunofluorescence by monoclonal antibody (25-1 McAb) derived from apodemus virus to both viral antigens, but antisera from mild EHF gave only low-grade blocking against apodemus viral antigen. Direct antigenic titrations of both viral strains by cross-ELISA yielded similar results. That distinct antigenic differences exist between viral strains causing these two types of EHF might be of great importance to the serological differentiation of the viruses and the study of EHF vaccine.

Etiologic studies of epidemic hemorrhagic fever (hemorrhagic fever with renal syndrome)

Two strains of epidemic hemorrhagic fever (EHF) virus were isolated from the lung tissues of Apodemus agrarius mice that were captured in an area where EHF is endemic. The strains were isolated by passages in A. agrarius mice from a nonendemic area. Identification of the isolates by usual procedures was confirmed by repeated blind tests with coded sera. Contamination with certain known viruses such as reovirus, adenovirus (types 3 and 7), and other pathogens, such as murine typhus rickettsiae and Leptospira, which may be naturally present in wild rodents, appeared to have been ruled out. The antigen slides made from these isolates are in use in the specific diagnosis and seroepidemiologic studies of EHF. The first successful application is the serodiagnosis of a mild type of hemorrhagic fever that occurs with characteristic epidemiologic features in certain provinces of China.