Modelling the black death. A historical case study and implications for the epidemiology of bubonic plague

We analysed a plague outbreak in the mining town of Freiberg in Saxony which started in May 1613 and ended in February 1614. This epidemic was selected for study because of the high quality of contemporary sources. It was possible to identify 1400 individual victims meaning that more than 10% of the population of the city perished. The outbreak was modelled by 9 differential equations describing flea, rat, and human populations. This resulted in a close fit to the historical records of this outbreak. An interesting implication of the model is that the introduction of even a small number of immune rats into an otherwise unchanged setting results in an abortive outbreak with very few human victims. Hence, the percentage of immune rats directly influences the magnitude of a human epidemic by diverting search activities of the fleas. Thus, we conclude that the spread of Rattus norvegicus, which might acquire partial herd immunity by exposure to soil- or water-borne Yersinia species due to its preference for wet habitats, contributed to the disappearance of Black Death epidemics from Europe in the 18th century. In order to prove whether or not the parameter values obtained by fitting a given outbreak are also applicable to other cases, we modelled the plague outbreak in Bombay 1905/06 using the same parameter values except for the number of humans as well as of immune and susceptible rats.     

Antihypertensive effects of captopril and saralasin in essential and renal hypertension

The antihypertensive effect of captopril and its mechanism of action were studied in patients with essential and renal hypertension. In mild essential hypertension (n = 12), during monotherapy with captopril (50 to 450 mg, 4 to 12 weeks) blood pressure was normalized in seven, improved in two and remained unchanged in three patients, plasma levels of active and acid-activatable inactive renin significantly increased and angiotensin II decreased, whereas no consistent changes in urinary kallikrein excretion occurred. In severe renal (n = 14) and essential (n = 9) hypertension, blood pressure was normalized in eight (seven with renal hypertension), improved in seven and unchanged in eight patients, when captopril (50 to 450 mg, 3 to 15 months) was added to the antihypertensive medication. In one patient with stenosis in a transplanted renal artery reversible renal failure occurred during captopril therapy possibly because of a steep initial decrease in blood pressure, although a toxic effect of the drug cannot be excluded. In another series of 12 renal and 8 essential hypertensive patients, a significant correlation between the acute effect of captopril (within 90 minutes) and saralasin on blood pressure was demonstrated (r = 0.71, p < 0.001). The change in blood pressure after either drug was significantly related to the initial plasma renin concentration.In conclusion, captopril sems to be an effective antihypertensive agent in essential and renal hypertension. Renal function should be monitored during captopril therapy. Our studies suggest that captopril decreases blood pressure by inhibiting the vasopressor action of the renin-angiotensin system.     

Die dorsoposteriore extraperitoneale Pelviskopie (DEP)

Background: Local resection of low-risk T1 carcinoma of the rectum is an accepted standard of treatment. In high-risk T1 tumors a standard resection should be considered due to the possibility of lymph node metastasis. The dorso-posterior extraperitoneal pelviscopy (DEP) is a method to explore and dissect the mesorectum as a staging procedure. Patients and Methods: We describe the results of ten patients with high-risk T1 rectal cancer in whom, following transanal R0 resection and conventional staging (CT scan, transanal endosonography and abdominal sonography) DEP was performed. The operation was carried out in general anesthesia, the patient in prone jack-knife position. The retrorectal space was dilated with a balloon through a dorso-posterior approach. The extraperitoneal pelvic structures were dissected with a three-port technique and CO₂ insufflation. Results: The procedures were performed without technical difficulty. With this method we could extract between four and 20 lymph nodes. In one patient micrometastases where detected. In the only one-stage procedure the patient developed an insufficiency of the transanal suture and a rectovaginal fistula. In a second patient we found an inertia recti 6 weeks postoperatively. Conclusion: A positive lymph node stage can only be diagnosed histologically. DEP is a method that aspires to achieve histological lymph node staging following local resection of high-risk T1 tumors, so that rectum-sparing treatment can be supported. Indications for rectum-sparing surgery could possibly also be extended to high-risk T1 tumors with this method.     

Cachexia in chronic heart failure: Prognostic implications and novel therapeutic approaches

Cachexia in patients with chronic heart failure (CHF) has been recognized for a long time; however, it has not received much attention until recently. Cardiac cachexia, a common and serious complication of CHF, is associated with very poor prognosis. Several studies have demonstrated that increased neurohormonal and immune abnormalities may play a crucial role in the pathophysiology of cardiac cachexia. Hormonal and catabolic/anabolic imbalances of the body are likely to be responsible for the development of cachexia in CHF. Recently, ghrelin, a novel growth hormone-releasing peptide, has been widely noticed to have potential in the treatment of severe CHF and cardiac cachexia. However, further research will be necessary to identify the exact pathways involved and to find the best therapeutic strategies of using ghrelin to fight the wasting process.     

Human exonuclease 1 and BLM helicase interact to resect DNA and initiate DNA repair

The error-free repair of double-stranded DNA breaks by homologous recombination requires processing of broken ends. These processed ends are substrates for assembly of DNA strand exchange proteins that mediate DNA strand invasion. Here, we establish that human BLM helicase, a member of the RecQ family, stimulates the nucleolytic activity of human exonuclease 1 (hExo1), a 5′→3′ double-stranded DNA exonuclease. The stimulation is specific because other RecQ homologs fail to stimulate hExo1. Stimulation of DNA resection by hExo1 is independent of BLM helicase activity and is, instead, mediated by an interaction between the 2 proteins. Finally, we show that DNA ends resected by hExo1 and BLM are used by human Rad51, but not its yeast or bacterial counterparts, to promote homologous DNA pairing. This in vitro system recapitulates initial steps of homologous recombination and provides biochemical evidence for a role of BLM and Exo1 in the initiation of recombinational DNA repair.     

Relevance of underlying disease and bacterial vacA and cagA status on the efficacy of Helicobacter pylori eradication

AIM: To study the effects of Helicobacter pylori associated diseases and the bacterial vacA and cagA statuses on the efficacy of H. pylori eradication. METHODS: A prospective study in a consecutive series of outpatients of a gastroenterological institution and of a primary practice. A series of 146 H. pylori positive patients with peptic ulcer disease (PUD; n = 40) or nonulcer dyspepsia (NUD; n = 106) were evaluated. H. pylori vacA genotpyes and cagA status were determined directly in gastric biopsy specimens by polymerase chain reaction. The patients were treated with triple-therapy regimens consisting of a proton pump inhibitor and two antibiotics twice daily for 7 days. Reevaluation of H. pylori was determined 4-5 weeks later by endoscopy or 13C urea breath test. RESULTS: 123 patients completed the study. In 8 patients, colonization with two or more H. pylori strains was found. The overall cure rate was 84.6% (104/123). The eradication rates were significantly higher in patients with PUD (94.4%, 34/36) than in those with NUD (81.6%, 71/87; p < 0.05). In patients with cagA-positive H. pylori strains, the eradication rate was 89.0% (73/82) as compared with 78.8% (26/33) in those with cagA-negative strains (p = 0.15). The vacA genotype had no effect on the efficacy of H. pylori eradication. CONCLUSION: Using 1-week triple-therapy regimens, treatment of H. pylori infection is more effective in patients with PUD than in those with NUD.     

Endoscopic vacuum-assisted closure of upper intestinal anastomotic leaks

BACKGROUND: Management of intrathoracic anastomotic leaks remains an interdisciplinary challenge. Established treatment options include percutaneous drainage, endoscopic closure, or even surgical revision. All these procedures are associated with high morbidity and mortality rates. OBJECTIVE: We report a new, effective endoscopic treatment option for intrathoracic esophageal anastomotic leaks by using an endoscopic vacuum-assisted closure system. PATIENTS: Two patients with intrathoracic anastomotic leaks after esophagectomy and gastrectomy were included. METHODS: Surgical reinterventions failed to seal the leaks in 1 patient, whereas in the other patient the anastomotic leakage persisted after endoscopic placement of 2 covered self-expanding metal stents. We endoscopically placed transnasal draining tubes that were armed with a size-adjusted sponge at their distal tip in the necrotic anastomotic cavities. Continuous suction was applied. Sponge and drain were changed twice a week. RESULTS: No complications were noted during the course of treatment. After a median of 15 days, closure of the wound cavities was achieved in all cases. A median of 5 endoscopic interventions was necessary. Both patients returned gradually to a solid diet without recurrence of the leaks. CONCLUSION: Endoscopic vacuum-assisted closure might be an effective alternative in the treatment of upper intestinal anastomotic leaks.     

Too little aspirin for secondary prevention after acute myocardial infarction in patients at high risk for cardiovascular events: Results from the MITRA study

Background

A meta-analysis of randomized trials has shown a significant reduction of mortality rate in patients receiving aspirin for secondary prevention after acute myocardial infarction (AMI). However, a significant number of patients do not receive aspirin after AMI. Little is known about why aspirin is withheld or the long-term outcome of these patients today.

Methods

The Maximal Individual Therapy in Acute Myocardial Infarction (MITRA) registry is a multicenter registry of patients with AMI in Germany.

Results

Of 4902 patients, 509 (10%) did not receive aspirin at the time of discharge from the hospital. The mean follow-up period for these patients was 17 months. Relative contraindications to aspirin were significantly associated with the withholding of aspirin (in-hospital bleeding: odds ratio [OR], 3.56; 95% CI, 1.86-6.80; history of peptic ulcer: OR, 2.49; 95% CI, 1.62-3.83). Absolute contraindications to aspirin were rare (2.2%). Other medications of proven benefit were also given less often in these patients (β-blockers: 49.0% vs 61.9%, P <.001; angiotensin-converting enzyme inhibitors: 65.6% vs 70.2%, P = .06; statins: 12.2% vs 15.1%, P = .10). Patients who were not given aspirin were at high risk for vascular events. They were more likely to have a history of prior AMI (OR, 1.34; 95% CI, 1.02-1.79), were in critical clinical condition at admission more often (cardiogenic shock: OR, 1.98; 95% CI, 1.09-3.56; overt heart failure: OR, 1.6; 95% CI, 1.05-2.3), and received acute revascularization less often (OR, 1.32; 95% CI, 1.05-1.67). The 1-year mortality was 2-times higher in patients who did not receive aspirin than in patients who did receive aspirin (16.5% vs 8.3%, P <.001). A significant association of withheld aspirin at discharge with a higher long-term mortality rate was confirmed with multivariate analysis (OR, 1.62; 95% CI, 1.15-2.29).

Conclusions

Ten percent of patients who sustained an AMI did not receive aspirin at the time of hospital discharge. Most of these patients were at high risk for cardiovascular events. Withheld aspirin was significantly associated with higher mortality rate during follow up.     

Non-Compaction-Kardiomyopathie

Isolated non-compaction of the ventricular myocardium (INVM), also known as left ventricular hypertrabeculation or spongy myocardium, belongs to the "unclassified" cardiomyopathies according to the World Health Organization. The main characteristic of this entity is a prominent trabeculation of the left ventricle with deep intertrabecular recesses communicating with the ventricular cavity. The pathomechanism of INVM is thought to be an arrest in cardiac myogenesis with persistence of embryonic myocardial morphology. The most frequent clinical manifestations include congestive heart failure, ventricular arrhythmias and systemic thromboembolic events. The therapy of INVM comprises standard medical therapy for heart failure.