Resuscitation-promoting factors are important determinants of the pathophysiology in Mycobacterium tuberculosis infection

Resuscitation promoting factors (Rpf) are peptidoglycan-hydrolyzing enzymes that are pivotal in the resuscitation of quiescent actinobacteria including Mycobacterium tuberculosis. From the published data, it is clear that Rpf are required for the resuscitation of non-replicating bacilli and pathogenesis in murine infection model of tuberculosis, although their direct influence on human Mycobacterium tuberculosis infection is ill-defined. In this review, we describe the progress in the understanding of the roles that Rpf play in human tuberculosis pathogenesis and importance of bacilli dependent upon Rpf for growth for the outcome of human tuberculosis. We outline how this research is opening up important opportunities for the diagnosis, treatment and prevention of human disease, progress in which is essential to attain the ultimate goal of tuberculosis eradication.     

Psychological and physical determinants of premenstrual symptoms before and after hysterectomy

The aim was to study women before and after hysterectomy (with conservation of the ovaries), in order to discover how far premenstrual symptoms are caused physically and how far psychologically. In such women both physical and psychological factors can influence premenstrual symptoms before hysterectomy; after the operation, in the absence of menstruation, only physical factors can do so. The subjects were 56 women awaiting hysterectomy for menorrhagia of benign origin. During three pre-operative months these women made daily self-ratings on a check-list in which typical premenstrual symptoms were interspersed with atypical symptoms; in this way their awareness of the premenstrual focus was minimized. Starting six months after hysterectomy, the women again kept daily check-lists for three months; over the same period their serum progesterone levels were measured to identify the premenstruum. After hysterectomy, levels of premenstrual symptoms fell significantly in the whole group, indicating that psychological factors were important determinants of such symptoms before hysterectomy.     

IglG and IglI of the Francisella pathogenicity island are important virulence determinants of Francisella tularensis LVS

The Gram-negative bacterium Francisella tularensis is the causative agent of tularemia, a disease intimately associated with the multiplication of the bacterium within host macrophages. This in turn requires the expression of Francisella pathogenicity island (FPI) genes, believed to encode a type VI secretion system. While the exact functions of many of the components have yet to be revealed, some have been found to contribute to the ability of Francisella to cause systemic infection in mice as well as to prevent phagolysosomal fusion and facilitate escape into the host cytosol. Upon reaching this compartment, the bacterium rapidly multiplies, inhibits activation of the inflammasome, and ultimately causes apoptosis of the host cell. In this study, we analyzed the contribution of the FPI-encoded proteins IglG, IglI, and PdpE to the aforementioned processes in F. tularensis LVS. The ΔpdpE mutant behaved similarly to the parental strain in all investigated assays. In contrast, ΔiglG and ΔiglI mutants, although they were efficiently replicating in J774A.1 cells, both exhibited delayed phagosomal escape, conferred a delayed activation of the inflammasome, and exhibited reduced cytopathogenicity as well as marked attenuation in the mouse model. Thus, IglG and IglI play key roles for modulation of the intracellular host response and also for the virulence of F. tularensis.     

Gene variants as determinants of longevity: focus on the inflammatory factors

Human longevity is an extremely complex trait with various genetic, epigenetic and environmental factors acting upon the longevity phenotype. It is now becoming evident that whilst the genetic differences contribute only modestly to life expectancy before the age of 60 years, their impact on survival becomes more prominent at the extreme ages. Several longevity gene candidates have emerged during the past decade; the majority of them are related either to inflammatory functions, stress response or to lipid and glucose metabolism. The variants of inflammatory and immune response genes are of special interest since advancing ages is accompanied by a decline in several immune functions—a phenomenon called immunosenescence. Paradoxically, ageing is also characterised by chronic low-grade inflammation termed “inflammaging”, which manifests as a two- to fourfold increase in the production of proinflammatory cytokines and acute phase proteins. These contrasting phenomena provide a functional rationale of how the genetic differences in inflammatory mediators may modify the life span of the elderly. Besides describing the pre-existing inflammatory and immune-related longevity gene variants, in this review, we also explain some of the theoretical and practical challenges that genetic longevity studies often encounter.     

How important are the dermatophytes? A clinical and laboratory investigation.

Dermatophyte infections were established in 6.9% of 640 unselected dermatology outpatients attending two district general hospitals in Cumbria over a six-month period. A clinical diagnosis of ringworm was confirmed in the laboratory in 43.1% of hospital and in 21.8% of a smaller series of general practice patients. No result of similar surveys have been published before., Even in a major stock-rearing area such as this, domestic pets appear to be a more important source of infection than the farm animal.     

Baropodometric analyses of patients before and after bariatric surgery

OBJECTIVE:The aim of this study was to evaluate the vertical component of the ground reaction force, plantar pressure, contact area of the feet and double-support time using static and dynamic (gait) baropodometry before and after bariatric surgery.METHODS:Sixteen individuals with a body mass index of between 35 and 55 were evaluated before and after bariatric surgery. Thirteen patients (81.3%) were female and three (18.8%) male and their average age was 46±10 (21-60) years. An FSCAN system (version 3848) was used for baropodometric analyses (1 km/h and 3 km/h). The peak plantar pressure and ground reaction force were measured for the rear foot and forefoot. The double-support time and foot contact area were measured during gait.RESULTS:There were reductions in the ground reaction force in the forefoot and rear foot and in the foot contact area in all evaluations and of the double-support time at 3 km/h, as well as a significant reduction in the body mass index at six months post-surgery. The peak pressure did not vary at 1 km/h and at 3 km/h, reductions in peak pressure were observed in the left and right rear feet and left forefoot.CONCLUSIONS:Weight loss after bariatric surgery resulted in decreases in the ground reaction force and contact area of the foot. Plantar pressure was decreased at 3 km/h, especially in the forefoot. There was an increase in rhythm because of a reduction in the double-support time at 3 km/h.     

肺部手术后动静脉栓塞危险因素和临床转归研究进展

据2019年数据统计,全国手术量达到了6 930万人次,其中肺部手术作为外科手术中的重要组成部分,且手术量逐年递增。但伴随手术量增加,围手术期的并发症也逐渐增多,而血栓作为围术期并发症之一,给患者的预后带来了不良影响。因此,了解肺部围手术期血栓形成的病因、危险因素、机制等,同时在肺部围手术期采取有效预防措施,可以减少因肺部手术而导致的血栓所带来的不良影响。本文将对肺部术后血栓的发病率、危险因素、临床表现、治疗和预后等展开论述,期望为相关临床研究提供新的认识。     

Beat-to-beat QT interval variability before and after cardiac surgery

Non-uniform recovery of excitability may be essential in triggering malignant ventricular tachycardia after cardiac surgery. Thirty-five channels ECG was recorded for 6 min in 27 patients before and after heart surgery and in 20 control subjects. Off-line analysis was performed. RR interval duration, RR SD, QT SD and power spectra of RR variability were computed from 256 s stable RR and QT interval series. When compared to controls, patients had decreased RR SD and increased QT SD before surgery (p<0.002 and p<0.0005, respectively); RR SD further decreased and QT SD increased after the surgery (p<0.0001 and p<0.0002, respectively). Increase of QT variability and decrease of RR variability after cardiac surgery may reflect disrupted electrophysiological stability of the myocardium and thus electrophysiological substrate for triggering malignant arrhythmia.     

Muscarinic acetylcholine receptors in the heart of rats before and after birth

Atropine-displaceable binding of (³H)quinuclidinyl benzilate (QNB) to homogenates was used to identify the muscarinic binding sites in rat heart atria and ventricles and to investigate developmental changes in their concentration and binding properties between the 15th day of prenatal life and 3 months after birth. On the 15th day of prenatal life, muscarinic binding sites were already present in the heart. Their concentration increased steeply between the 15th and 19th days of prenatal development; in the atria, it remained high until the 1st day after birth and thereafter it diminished throughout the postnatal life, while in the ventricles the decrease started before the first postnatal day. The concentration of the binding sites was 1.8–3.0 times higher in the atria than in the ventricles at all time points investigated. Their affinity for QNB (the antagonist) was the same in the atria and ventricles and did not change during postnatal development (K _D of 17.8 pmol/l at an infinitely low concentration of the binding sites). The binding of carbamoylcholine (the agonist) to muscarinic bindig sites was analysed in experiments with the displacement of (³H)QNB binding, assuming the presence of high- and low-affinity binding sites for agonists. The proportion between the concentrations of the two classes of agonist binding sites is close to 1:1 both in the atria and the ventricles and does not change with age. No statistical significant differences were discovered between the affinities of the high- and low-affinity binding sites for carbamoylcholine between the atria and the ventricles and between new-born and adult rats. It is suggested that the steep increase in the number of muscarinic binding sites between the 15th and 19th days of prenatal development is triggered by the arrival of nerve cells and fibres into the heart (occuring on the 14th–16th day) and that it is one of the factors responsible for the onset of effective neuro-effector transmission in the heart (21st day of prenatal development). The commencement of tonic cardioinhibitory vagal control (18th day after birth) appears unrelated to developmental changes of cardiac muscarinic binding sites.     

The retroperitoneal resection margin and vessel involvement are important factors determining survival after pancreaticoduodenectomy for ductal adenocarcinoma of the head of the pancreas

 The prognosis of ductal adenocarcinoma of the pancreas is still poor. We analysed the factors that have a major influence on the survival of patients. Surgical specimens from 51 patients with ductal adenocarcinoma of the head of the pancreas were examined for tumour size, histological type, grade and local extension. In 7 patients the retroperitoneal resection margin was involved either macroscopically or histologically. Their mean survival was 10.6 months (1–17 months), compared with 22.7 months for the 44 patients with curative R0 resection. In 10 patients large vessels (portal and/or mesenteric vein) had to be resected; they survived for only 2-11 months, with a mean of 5 months (P<0.05). Non-R0-resected patients and patients in whom tumour-invaded vessels had to be resected constitute a high-risk group with a significantly shorter mean survival of 8.8 months, compared with 24.3 months for R0 resected patients without vessel invasion (P<0.05). Lymph node metastases were seen in 35 of 51 patients. Survival analysis based on nodal status revealed a mean survival of 33 months for patients staged as N0, 21.4 for N1a patients and 14 month for N1b patients. The differences were not statistically significant, however. Our data suggest that tumour invasion of the retroperitoneal resection margin and large vessel involvement are the major factors determining survival in patients with pancreatic cancer. Received: 15 December 1998 / Accepted: 26 April 1998     

Histologic and endoscopic studies before and after gastric bypass surgery

The purposes of this study were to establish a standardized multiparameter analysis system for histologic grading of gastritis and to compare histologic changes with endoscopic findings in the proximal and distal bypassed stomach in obese patients undergoing gastric bypass surgery. Three groups, comprising a total of 91 patients, were studied: a preoperative group (34 patients), a postoperative group at one year (33 patients), and a postoperative group at two years (24 patients). the biopsy specimens from the proximal and distal bypassed stomach were compared in all groups. Seventeen histologic variables were evaluated by three observers to classify the severity of gastritis. Forty percent of the patients in the postoperative group demonstrated histologic evidence of nonerosive, superficial gastritis, slightly more in the proximal stomach. Endoscopy showed significantly more bile reflux and inflammation in the distal stomach than the proximal stomach in nearly all patients. Our study demonstrates a significant discrepancy between bile reflux observed endoscopically and the histologic findings after gastric bypass surgery. No metaplastic or dysplastic changes were found up to two years postoperatively, but further studies are needed to determine the long-term endoscopic and histologic endoscopic and histologic sequelae of gastric bypass surgery.     

Alloantibodies and Australia antigen after open heart surgery

The development of irregular serum antibodies (alloantibodies) following massive transfusion was studied in 144 patients who had undergone cardiac valve replacement. An overall incidence of alloimmunization of 8.3% was found. Of the 15 antibodies detected nine were Rhesus anti-E and four anti-Kell. The incidence of anti-E formation in Rhesus E-negative patients was 11.4%; the corresponding figure for anti-Kell was 3.2%. The results suggest that the risk of allo-immunization is directly related to the volume of blood transfused, and Rhesus E-negative persons appear to be at particular risk.Australia (Au) antigen investigations were also carried out in 102 of these cases. Three patients were Au antigen positive, one of them developing acute hepatitis. In each case no Au antigen could be detected in the donor blood that was used.It is suggested that tests for alloantibodies and for the Australia antigen should become part of the routine follow-up of any patient receiving massive transfusion.