A mutation in a Rhodobacter capsulatus gene encoding an integration host factor-like protein impairs in vivo hydrogenase expression.

A gene capable of encoding a protein sharing 45% identical amino acids with the alpha subunit of the integration host factor (IHF) of Escherichia coli was isolated from the photosynthetic bacterium Rhodobacter capsulatus strain B10 by complementation of a hydrogenase-deficient (Hup-) mutant, IR4. A DNA fragment of 274 base pairs containing an IHF binding consensus sequence, isolated from the promoter region of the hydrogenase structural genes (hupSL), was shown by gel retardation assays to bind the IHF protein from E. coli. The product of the R. capsulatus gene was shown to bind specifically to the 274-base-pair DNA fragment from the hupSL promoter. By analogy to the E. coli himA gene, which encodes the alpha subunit of IHF, the gene complementing the IR4 mutant was named himA of R. capsulatus. The wild-type himA gene, cloned in plasmid pBO2, was introduced into the IR4 strain and shown to restore, in trans, hydrogenase activity and autotrophic growth in the mutant. In IR4, a C----T transition mutation had replaced Arg-8 by Cys-8. Gel mobility shifts of the 274-base-pair DNA fragment, not observed with the himA gene product of IR4, were restored with extracts from IR4(pBO2) cells, containing the himA gene on the recombinant plasmid pBO2.     

Allogeneic bone marrow transplantation for chronic myeloid leukemia in first chronic phase: a randomized trial of busulfan-cytoxan versus cytoxan-total body irradiation as preparative regimen: a report from the French Society of Bone Marrow Graft (SFGM)

From March 1988 to March 1991, 19 French bone marrow transplant (BMT) centers participated in a prospective randomized trial comparing two conditioning regimens for patients with chronic myeloid leukemia transplanted in first chronic phase with an HLA identical sibling donor. A total of 120 consecutive patients were randomized to receive either 120 mg/kg of cyclophosphamide followed by total body irradiation (CY-TBI; n = 55) or 16 mg/kg of busulfan followed by 120 mg/kg of CY (BU-CY; n = 65). Two different TBI regimens were used. Thirteen patients received a 10-Gy single-dose TBI (SDTBI), and 42 received a fractionated TBI (FTBI). Median time between diagnosis and BMT was 315 days. Overall 5-year actuarial survival was 62.9% (65.8% +/- 12.5% for CY-TBI and 60.6 +/- 11.7% for BU-CY; P = .5), and overall disease-free survival was 55% (51% +/- 14% for CY-TBI and 59.1% +/- 11.8% for BU-CY; P = .75). All patients conditioned with CY-TBI experienced sustained engraftment; in contrast, 4 of 65 patients conditioned with BU-CY rejected the graft (P = .18). There was no significant statistical difference between the two groups regarding transplant-related mortality (29% for CY-TBI and 38% for BU-CY; P = .44). So far, with a median follow up of 42 months, 11 patients have relapsed; 9 relapses occurred after CY-TBI, mostly after FTBI (8 of 9) and 2 after BU-CY (P = .02). The actuarial risk of relapse was 4.4% +/- 6.7% after BU-CY, 11.1% +/- 20.8% after SDTBI, and 31.3% +/- 18.1% after FTBI (P = .039). In addition, independently of the conditioning regimen, the increase of posttransplant immunosuppression in 16 patients with an anti- interleukin-2 receptor monoclonal antibody (MoAb) in addition to a short course of methotrexate and cyclosporine was shown to increase the actuarial risk of relapse (57% +/- 30% with MoAb v 9% +/- 7.3% without MoAb; P = .001). We conclude that BU is an acceptable alternative to TBI for patients with chronic myeloid leukemia in first chronic phase receiving BMT from HLA identical sibling donors. Both BU-CY and CY-TBI regimens gave similar transplant-related mortality, and the antileukemic efficiency of BU-CY regimen was either similar or even higher than that of CY-TBI.     

Finite element model of the impaction of a press-fitted acetabular cup

Press-fit surgical procedures aim at providing primary stability to acetabular cup (AC) implants. Impact analysis constitutes a powerful approach to retrieve the AC implant insertion properties. The aim of this numerical study was to investigate the dynamic interaction occurring between the hammer, the ancillary and bone tissue during the impact and to assess the potential of impact analysis to retrieve AC implant insertion conditions. A dynamic two-dimensional axisymmetric model was developed to simulate the impaction of the AC implant into bone tissue assuming friction at the bone–implant interface and large deformations. Different values of interference fit (from 0.5 to 2 mm) and impact velocities (from 1 to 2 m.s^?1) were considered. For each configuration, the variation of the force applied between the hammer and the ancillary was analyzed and an indicator I was determined based on the impact momentum of the signal. The simulated results are compared to the experiments. The value of the polar gap decreases with the impact velocity and increases with the interference fit. The bone–implant contact area was significantly correlated with the resonance frequency (R ² = 0.94) and the indicator (R ² = 0.95). The results show the potential of impact analyses to retrieve the bone–implant contact properties.     

Tumours of the retrorectal space: management and outcome of a heterogeneous group of diseases

Aim  Retrorectal tumours are a rare and complex entity in adults and children. They present a varied symptomatology and their treatment is very different according to their histology. We aimed to evaluate our experience of tumours of the retrorectal space. Method  Forty patients with retrorectal tumours were divided into two groups according to age. The variables analysed were sex, signs and symptoms, complementary examinations, surgical approaches, adjuvant therapies, pathological analyses, recurrence and survival. Results  Symptoms across the 30 adults varied – back pain (18) was the most common. Surgical intervention was performed on 20 patients; the rest were candidates for other treatments: five metastatic disease, two lymphomas and two Ewing tumour. The most common surgical approach was posterior, with 10 cases (50%). In all, 70% of adult tumours were malignant, with chordoma (30%) and metastases (20%) being the most common lesions. The most frequent benign lesion was hamartoma (10%). The 1‐ and 5‐year mortality rates were 23.8% and 38.1%, respectively. In the paediatric group, three patients were diagnosed in utero. The symptoms among children varied and all were operated upon. The most frequent tumour was teratoma. Overall mortality was 20%. Conclusions  Given their complexity, these tumours should be addressed by experts and all treatment options must be contemplated. They continue to present a challenge, above all in malignant tumours where the tumour cannot be controlled at a locoregional level.     

Serum interleukin-10 in non-Hodgkin's lymphoma: a prognostic factor

Serum interleukin-10 (IL-10) was measured retrospectively in 153 patients with a fully documented history of non-Hodgkin's lymphoma (NHL) using an enzyme-linked immunosorbent assay (ELISA) detecting both human IL-10 and the Epstein-Barr virus (EBV) molecule BCRF1/viral IL- 10. IL-10 was detectable in 47 (46%) of the 101 patients with active NHL, 3 of 52 (6%) patients in first partial or complete response, and none of the 60 healthy blood donors. Serum IL-10 was detectable with a similar frequency in all subtypes of NHL and in all clinical stages, as well as in EBV-seropositive and EBV-negative patients. In patients with intermediate or high-grade NHL, the presence of detectable serum IL-10 at diagnosis was correlated to a significantly shorter overall (P = .025) and progression-free (P = .030) survival. Patients with stage IV disease and detectable serum IL-10 had a particularly poor prognosis (4 years of survival: 0%). Multivariate analysis showed that IL-10 was an independent prognosis factor. These results indicate that IL-10 is detectable in a subgroup of patients with active NHL and correlates to a poor survival in patients with intermediate or high-grade NHL.     

Retrospective Outcome Analysis of 39 Patients Who Underwent Lip Surgery for Cutaneous Carcinoma

Purpose

The treatment of lip carcinomas needs tumor surgical resection with safety margins respect. The aim of this study was to report the oncologic and aesthetic/functional outcomes of a retrospective monocentric case series of 39 patients treated for cutaneous lip cancer.

Methods

This retrospective study assessed 56 patients who were treated for a lip carcinoma between 2008 and 2012 and included 39 patients with cutaneous lip basal cell carcinoma or squamous cell carcinoma. Clinical, surgical and pathological data were reviewed, and patients were interviewed for follow-up data. A comparison was made between the marked surgical margins and the margins observed under microscopy after histologic process.

Results

The most frequent tumor type was basal cell carcinoma in 69.2 %. The measured surgical margins were superior to the histological margins in 24 cases (61.5 %) and were inferior in 13 cases (33.3 %). Overall survival and recurrence-free survival rates at 1 year were 97.5 and 95 % respectively.

Conclusion

Differences between the surgical margins and the final histologic margins were the main finding of this retrospective study. These differences were attributed to surgical practices and modification during the histological process. Nevertheless, we did not observe a higher rate of recurrence or death in our study than in literature.

     

Bioprosthetic Valve Thrombosis and Obstruction Secondary to COVID-19

Patients with COVID-19 may present a hypercoagulable state, with an important impact on morbidity and mortality. Because of this situation pulmonary embolism is a frequent complication during the course of infection. We present the case of a patient recently discharged, after admission with confirmed COVID-19, who developed a pulmonary embolism and thrombosis of a biological mitral valve prosthesis, producing valve obstruction and stenosis. After 15 days of anticoagulant treatment, resolution of the thrombus and normalisation of prosthetic valve function was observed. This case supports current recommendations of administering full-dose anticoagulation therapy to COVID-19 patients with biological heart valve prosthesis, even after the acute phase of infection.     

Improved glucose tolerance in acyl CoA:diacylglycerol acyltransferase 1-null mice is dependent on diet

Background  

Mice that lack acyl CoA:diacylglycerol acyltransferase (Dgat1 ^-/- mice) are reported to have a reduced body fat content and improved glucose tolerance and insulin sensitivity. Studies so far have focussed on male null mice fed a high fat diet and there are few data on heterozygotes. We compared male and female Dgat1 ^-/-, Dgat1 ^+/- and Dgat1 ^+/+ C57Bl/6 mice fed on either standard chow or a high fat diet.     

假细锥香茶菜新二萜成分——假细锥甲素的结构

从假细锥香茶菜(Rabdosia coetsoides C.Y.Wu)叶分离得到新二萜成分,根据紫外光谱、红外光谱、质谱、核磁共振氢谱及碳谱等分析,推定了化学结构,并经X-射线衍射确证,命名为假细锥甲素。