Caspases-dependent cleavage of mitotic checkpoint proteins in response to microtubule inhibitor

The mitotic checkpoint ensures the fidelity of chromosomal segregation by delaying the onset of anaphase until all chromosomes are aligned on the metaphase plate. After sustained mitotic arrest, however, cells eventually exit mitosis without the mitotic checkpoint being silenced. These cells then undergo apoptosis, an event that is important for prevention of the chromosomal instability observed in human cancers. An interesting question is to establish the biochemical link between the mitotic checkpoint and the subsequent apoptotic cell death. Here, we found that following prolonged spindle damage, the mitotic checkpoint kinases such as Bub1 and BubR1 were cleaved through a mechanism sensitive to caspases inhibitor. Interestingly, the expression of these mutants resistant to caspases-dependent cleavage led to increased apoptosis after sustained mitotic arrest, and a correspondingly more efficient elimination of the polyploid population than that seen in cells expressing wild-type proteins. These findings provide the novel biochemical properties of mitotic checkpoint proteins through its cleavage by caspases-dependent manner.     

Domiciliary oxygen: rationalization of supply in the Hunter region from 1982-1986

In October 1982, a clinic was planned at The Royal Newcastle Hospital to review the usage of domiciliary oxygen that was funded by the Provision of Aids for Disabled Persons scheme in the Hunter Region of New South Wales. Patient review included an assessment of the indications for domiciliary oxygen, education in the use of oxygen, the efficiency of delivery arrangements and the transfer from cylinders to concentrators as indicated. Between January and June 1983, 111 patients who were receiving oxygen at home were reviewed: 84 (76%) of these patients had chronic obstructive pulmonary disease; their two-year survival was 80% (95% confidence interval, 69%-87%) and five-year survival was 36% (95% confidence interval, 25%-46%). In 66 (59%) patients, review led to a reduction in the usage of domiciliary oxygen which was estimated to save $40,000 each year in the Hunter Region. In the year from 1985-1986 the decrease in the usage of oxygen at home represented an actual cost saving of $60,000 for the region ($470 per person) which translated into a saving of $95,000 ($740 per person) when inflation was taken into account. If our experience is projected nation-wide, the potential exists for a considerable cost saving by means of programmes to rationalize the use of domiciliary oxygen.     

LGI1 and CASPR2 neurological autoimmunity in children

The clinical phenotype of leucine‐rich glioma‐inactivated protein 1 (LGI1) and contactin‐associated proteinlike 2 (CASPR2) autoimmunity is well defined in adults. Data for children are limited (<10 cases). Among 13,319 pediatric patients serologically tested for autoimmune neurological disorders (2010–2017), 264 were seropositive for voltage‐gated potassium channel‐complex–IgG (radioimmunoprecipitation). Only 13 (4.9%) were positive by transfected cell‐binding assay for LGI1‐IgG (n = 7), CASPR2‐IgG (n = 3), or both (n = 3). This is significantly less than in adults. Encephalopathy, seizures, and peripheral nerve hyperexcitability were common, as was coexisting autoimmunity. No faciobrachial dystonic seizures or cancers were identified. Functional neurologic disorders were frequently the initial diagnosis, and immunotherapy appeared beneficial. Ann Neurol 2018;84:473–480     

Pain, depression, and fatigue as a symptom cluster in advanced cancer

Context

Pain, depression, and fatigue are common symptoms in cancer populations. They often coexist and have been suggested as a specific symptom cluster. Systemic inflammation (SI) may be a possible common mechanism.

Objective

This study examined whether pain, depression, and fatigue exist as a symptom cluster in advanced cancer patients with cachexia and might be related to the presence of SI.

Methods

Secondary data analysis was undertaken of two clinical trials in patients with cancer cachexia (n = 654). Pain, depression, and fatigue were assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30. Plasma C-reactive protein (CRP) was measured as a marker of SI in a subgroup (n = 436). Multivariate analysis and a series of regression analyses were undertaken relating pain, depression, fatigue, and CRP.

Results

Pain, depression, and fatigue clustered, with between two and four times as many patients having all three symptoms as would be expected if the symptoms only coexist by chance (P < 0.001). CRP was not related to the symptom cluster. There was a strong relationship between the pattern of symptoms and physical functioning (P < 0.001).

Conclusion

Pain, depression, and fatigue is an identifiable symptom cluster in a cohort of cachexic cancer patients and is associated with reduced physical functioning.     

Re-innervation of smooth muscle that is transplanted to provide urethral sphincter augmentation

A number of methods to augment the resistance of the outlet of the urinary bladder and to improve continence have been developed, including the artificial urinary sphincter and the placement of skeletal muscle around the urethra. It has been recently shown in a rabbit model that transplantation of smooth muscle around the proximal urethra reduces incontinence caused by internal sphincter deficiency. In the present work we have investigated the re-innervation of a peri-urethral smooth muscle transplant, and whether re-innervating axons have an appropriate effect when they are stimulated. Detrusor muscle from the dome of the bladder was transplanted to encircle the proximal urethras of rats. Rats tolerated the surgery and transplantation without any signs of compromised health. At 8 weeks the new sphincter was intact and easily recognised. The transplant contracted in response to transmural stimulation (1–5 Hz for up to 5 min) in a similar way to freshly removed detrusor strips. Contractions were graded with stimulus frequency, they peaked at about 10 s and faded to a lower tension that was maintained. The amplitudes of sustained contractions of the transplants were reduced to about 10% by hyoscine and were almost abolished by tetrodotoxin. Histological examination revealed healthy, vascularised smooth muscle in the transplants, similar in appearance to freshly dissected detrusor. Re-innervation was confirmed immunohistochemically for transplanted detrusor muscle and transplants of dartos muscle. We conclude that smooth muscle transplanted to form a new sphincter around the urethra becomes functionally re-innervated and has potential to be used for sphincter augmentation.