Detection of anti-HTLV-I Tax antibodies in HTLV-I enzyme-linked immunosorbent assay-negative individuals

The HTLV-I tax gene protein (Tax) is not packaged within the mature viral particle from which the proteins for the commercially available enzyme-linked immunosorbent assay (ELISA) are derived. Screening of 162 individuals within a cohort of white intravenous (IV) drug abusers, previously identified as having an increased incidence of HTLV-I infection, demonstrated that seven of them had antibodies to the HTLV-I Tax protein but tested negative in HTLV-I ELISAs and Western blots prepared from purified virion proteins. Three out of 35 individuals in other behaviorally defined high-risk groups also displayed this limited pattern of reactivity to HTLV-I proteins. The presence of the anti-HTLV- I p40/Tax antibodies was determined by radioimmunoprecipitation assay (RIPA), which also revealed low levels of anti-env reactivity. The specificity of the anti-p40 reactivity was confirmed on specific Tax ELISAs and Western blots prepared from recombinantly produced Tax. In vitro gene amplification by the polymerase chain reaction (PCR) was used to establish the presence of sequences homologous to HTLV-I proviral DNA in four/four of these HTLV-I ELISA negative, Tax ELISA/Tax western blot/RIPA positive individuals. These data suggest that the true incidence of HTLV-I infection within high-risk cohorts is greater than previously reported.     

The provision of a time-critical elective surgical service during the COVID-19 Crisis: a UK experience

IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery.     

Perioperative Net Fluid Balance Predicts Pancreatic Fistula After Pancreaticoduodenectomy

Background

Our goal was to evaluate the relationship between perioperative fluid administration and the development of clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD).

Methods

Retrospectively, we analyzed fluid balance over the first 72 h in 104 consecutive patients who underwent PD between 2013 and 2017. Patients were categorized into tertiles (low, medium, and high) by net fluid balance.

Results

POPF was identified in 17.3% of patients (n?=?18). No significant demographic differences were identified among tertiles. Similarly, there were no differences in ASA, smoking status, hemoglobin A1C, pathologic findings, operative time, blood loss, intraoperative fluid administration, use of pancreatic stents, use of epidurals, or postoperative lactate. Patients with high 72-h net fluid balance had significantly increased rates of POPF compared with those in the medium and low tertiles (31.4% vs. 11.4% vs. 8.8%, p?=?0.02). On multivariate analysis, increasing net fluid balance remained associated with CR-POPF (OR 1.26, CI 1.03–1.55, p?=?0.03).

Conclusion

High net 72-h fluid balance is an independent predictor of POPF after PD. Given ongoing efforts to minimize PD morbidity, net fluid balance may represent a clinical predictor and, possibly, a modifiable target for prevention of POPF.

     

Physiopathologie de la prééclampsie

Preeclampsia is agestational complication that classically appears from the start of the second trimester and which is specific to humans.     

Obesity predisposes to Th17 bias

Obesity is associated with numerous inflammatory conditions including atherosclerosis, autoimmune disease and cancer. Although the precise mechanisms are unknown, obesity‐associated rises in TNF‐α, IL‐6 and TGF‐β are believed to contribute. Here we demonstrate that obesity selectively promotes an expansion of the Th17 T‐cell sublineage, a subset with prominent pro‐inflammatory roles. T‐cells from diet‐induced obese mice expand Th17 cell pools and produce progressively more IL‐17 than lean littermates in an IL‐6‐dependent process. The increased Th17 bias was associated with more pronounced autoimmune disease as confirmed in two disease models, EAE and trinitrobenzene sulfonic acid colitis. In both, diet‐induced obese mice developed more severe early disease and histopathology with increased IL‐17⁺ T‐cell pools in target tissues. The well‐described association of obesity with inflammatory and autoimmune disease is mechanistically linked to a Th17 bias.     

18F‐fluorodeoxyglucose positron emission tomography imaging in brain tumours: The Western Australia positron emission tomography/cyclotron service experience

¹⁸F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) scans in the first 49 patients referred with either possible brain tumour or brain tumour recurrence were reviewed. FDG‐PET imaging was reported with reference to anatomical imaging. Based on the report the FDG study was classified as either positive or negative for the presence of tumour. Thirty‐eight cases were included in the analysis, 21 having pathological data and 17 with diagnostic clinical follow up. Eleven were excluded, as they had inadequate follow‐up data. Of the 21 cases with pathology, 18 were shown to have tumour. In this group there were five false‐negative scans and two false‐positive PET scans. Seventeen cases were assessed by clinical follow up, nine were considered to have been tumour. There were two false negatives with one false positive. The overall sensitivity, specificity and positive and negative predictive values were 74, 73, 87 and 53% respectively. This is similar to figures previously quoted in published work. Despite relatively limited numbers, the utility of FDG PET imaging in our hands is similar to published reports. With a positive predictive value of 87%, a positive FDG study indicates a high likelihood that there is brain tumour present. A negative study does not exclude the presence of tumour.     

Correlation of human spermatozoa heparin binding with the zona-free hamster egg in vitro penetration assay

The purpose of our research was to determine whether heparin-binding characteristics of human spermatozoa are related to fertilizing potential, as determined by the hamster egg in vitro penetration assay. Penetration rates were standardized (hamster egg in vitro penetration assay index) by comparison with semen from fertile controls in each bioassay. Saturation of heparin-binding domains was achieved in 100% of raw ejaculates (prewash), but in only 53% of "swim-up" (postwash) samples. The dissociation constants ranged from 0.31 to 48.75 nmol/10(6) cells, and binding site concentrations from 0.47 to 20.82 x 10(17) binding sites/cell. Heparin-binding affinity was significantly greater in prewash compared with postwash samples (p less than 0.01). In prewash samples the number of binding sites differed significantly between subjects having low and high penetration indices (5.67 +/- 1.05 vs 2.01 +/- 0.34 x 10(17) binding sites/cell, p less than 0.05). In prewash samples, binding affinity for heparin significantly correlated with hamster egg in vitro penetration assay indices (R2 = 0.142, p less than 0.05). In contrast, the number of binding sites in prewash samples was negatively correlated with hamster egg in vitro penetration assay indeces (R2 = 0.201, p less than 0.05). These data indicate that the heparin-binding assay may prove to be a rapid, sensitive, and inexpensive means of assessing fertilizing potential of human spermatozoa.