Sleeve urethroplasty: New technique

A single-stage urethroplasty for penile urethral stricture is described. This method obviated some of the common complications, such as fistula formation. This operation was performed on 11 patients with encouraging results. Further study is needed to assess its ultimate value.     

Methods for siting emergency stomas in the absence of a stoma therapist

Introduction

Stomas often have to be sited in emergencies by trainees who may have had little training in this. Emergency stomas and stomas where the site has not been marked preoperatively by a stoma therapist are more prone to complications. These complications may severely affect a patient’s quality of life. Advice in the literature on how to best site stomas is conflicting. We compared two easy anatomical methods of siting stomas to sites chosen by a stoma therapist and looked at how this site was affected by the patients’ body mass index (BMI).

Methods

Patients undergoing elective colorectal surgery were seen either pre or postoperatively. Each patient’s BMI was recorded and the positions of three different potential stoma positions (site G: the gold standard, marked by a stoma therapist; site S: marked using a pair of scissors against the umbilicus; site H: halfway between the umbilicus and anterior superior iliac spine) were compared.

Results

The two fixed anatomical methods described (method S and method H) both gave poor results. The most common reason for poor siting was the proximity of a skin crease. There was a statistically significant correlation between the patient’s BMI and the laterality of the gold standard site.

Conclusions

The two simple anatomical methods described here do not provide a shortcut to effective siting. A more effective method may be calculating the laterality of the site using the patient’s BMI, and then moving up/down to avoid a skin crease and improve the patient’s view for changing the bag. This deserves further study.     

VEGFA From Early Osteoblast Lineage Cells (Osterix+) Is Required in Mice for Fracture Healing

Bone formation via intramembranous and endochondral ossification is necessary for successful healing after a wide range of bone injuries. The pleiotropic cytokine, vascular endothelial growth factor A (VEGFA) has been shown, via nonspecific pharmacologic inhibition, to be indispensable for angiogenesis and ossification following bone fracture and cortical defect repair. However, the importance of VEGFA expression by different cell types during bone healing is not well understood. We sought to determine the role of VEGFA from different osteoblast cell subsets following clinically relevant models of bone fracture and cortical defect. Ubiquitin C (UBC), Osterix (Osx), or Dentin matrix protein 1 (Dmp1) Cre-ERT2 mice (male and female) containing floxed VEGFA alleles (VEGFA^fl/fl) were either given a femur full fracture, ulna stress fracture, or tibia cortical defect at 12 weeks of age. All mice received tamoxifen continuously starting 2 weeks before bone injury and throughout healing. UBC Cre-ERT2 VEGFA^fl/fl (UBC cKO) mice, which were used to mimic nonspecific inhibition, had minimal bone formation and impaired angiogenesis across all bone injury models. UBC cKO mice also exhibited impaired periosteal cell proliferation during full fracture, but not stress fracture repair. Osx Cre-ERT2 VEGFA^fl/fl (Osx cKO) mice, but not Dmp1 Cre-ERT2 VEGFA^fl/fl (Dmp1 cKO) mice, showed impaired periosteal bone formation and angiogenesis in models of full fracture and stress fracture. Neither Osx cKO nor Dmp1 cKO mice demonstrated significant impairments in intramedullary bone formation and angiogenesis following cortical defect. These data suggest that VEGFA from early osteolineage cells (Osx+), but not mature osteoblasts/osteocytes (Dmp1+), is critical at the time of bone injury for rapid periosteal angiogenesis and woven bone formation during fracture repair. Whereas VEGFA from another cell source, not from the osteoblast cell lineage, is necessary at the time of injury for maximum cortical defect intramedullary angiogenesis and osteogenesis. © 2019 American Society for Bone and Mineral Research.     

Immunologic heterogeneity of diffuse large cell lymphoma

The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs.     

Computer graphics for digitally formatted images

The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.     

Assessment of Genetic Fidelity Using Random Amplified Polymorphic DNA and Inter Simple Sequence Repeats Markers of <Emphasis Type="Italic">Lawsonia inermis</Emphasis> L. Plants Regenerated by Axillary Shoot Proliferation

An efficient, reliable and reproducible plant regeneration protocol was developed for Lawsonia inermis L. using mature nodal explants. Shoot proliferation (81.6 %) with 7.8 shoots/explant was achieved on Murashige and Skoog’s (MS) medium supplemented with 1.0 mg l^?1 6-benzyladenine. Shoot numbers were up-scaled by inducing multiple shoots from axenic nodal segments derived from the primary shoots on the shoot regeneration medium. Thus the authors could achieve ca. 129–134 shoots from single nodal explant. Ninety-three percent rooting of in vitro regenerated shoots was achieved on growth regulator free half-strength MS medium. Regenerated plantlets were successfully transferred to soil with 85 % survival rate. Genetic stability analyses of the in vitro regenerated plants using random amplified polymorphic DNA and inter simple sequence repeat markers revealed a homogeneous amplification profile for all micropropagated plants. This is the first report that evaluates the use of molecular markers to establish genetic fidelity of micropropagated L. inermis for the rapid clonal multiplication and true-to-type production of plant for attaining the ever increasing demand in pharmaceutical industries.     

Conjugation to Ascorbic Acid Enhances Brain Availability of Losartan Carboxylic Acid and Protects Against Parkinsonism in Rats

Identification of renin-angiotensin system in the interplay of hypertension and neurodegeneration has paved the way for the repurposing of antihypertensive drugs against Parkinsonism. Losartan carboxylic acid (LCA), the potent AT1 blocker metabolite of losartan, suffers from poor bioavailability and brain access. Since ascorbate transporters have earlier shown enough flexibility as carriers, we have conjugated losartan carboxylic acid to ascorbic acid with the aim of achieving higher oral/brain availability. Ester of LCA and ascorbic acid (FED) was developed keeping in view the substrate specificity of ascorbate transporters. Oral/brain bioavailability was assessed using in vivo pharmacokinetic model. Effect on central nervous system (CNS) and protection against Parkinsonism was evaluated using in vivo models. FED enhanced bioavailability of LCA. The higher brain availability of LCA enabled CNS protection as evident from the increase in locomotor activity, improved motor coordination, and protection against drug-induced catatonia. In conclusion, FED offers an approach to repurpose LCA against Parkinsonism. This can encourage further investigation to simultaneously address hypertension and neurodegeneration.     

The constrictor knot is the best ligature

Introduction

An ideal ligature should tighten readily and remain tight. Ligature failure can be a critical complication of invasive procedures in human and veterinary surgical practice. Previous studies have tested various knots but not the constrictor knot.

Methods

A new test bench was employed to compare six ligatures using four suture materials. As tension in a ligature is not readily measured, the study employed a surrogate measurement: the force required to slide a ligature along a rod. Benchmark values tested each suture material wrapped around the rod to establish the ratio between this force and the ligature tension for each material. Each ligature was tested first during tightening and then again afterwards. The benchmark ratios were employed to calculate the tensions to evaluate which ligature and which suture material retained tension best.

Results

The model provided consistent linear relationships between the tension in the suture and the force required to pull the ligature along the rod. The constrictor knot retained tension in the ligature best (55–107% better than the next best ligature). Among the suture materials, polydioxanone had the greatest ability to retain the tension in a ligature and polyglactin the least.

Conclusions

The constrictor knot showed superior characteristics for use as a ligature, and should be introduced into teaching and clinical practice for human and veterinary surgery. The new test bench is recommended for future testing of ligatures as well as objective comparison of suture materials.