Reactivation of heat-inactivated Ku proteins by heat shock cognate protein HSC73

Purpose: Mouse double-stranded DNA-dependent protein kinase (DNA-PK) activity is heat sensitive. Recovery of heat-inactivated DNA repair activity is a problem after combination therapy with radiation and heat. We investigated the mechanism of recovery of heat-inactivated DNA-PK activity.

Methods: Hybrid cells containing a fragment of human chromosome 8 in scid cells (RD13B2) were used. DNA-PK activity was measured by an in vitro assay. Immunoprecipitation of the nuclear extract was performed with an anti-Ku80 antibody. Proteins co-precipitated with Ku80 were separated by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and detected by Western blotting using anti-heat shock protein (HSP)72 and anti-heat shock cognate protein (HSC)73 antibodies. HSC73 was overexpressed with the pcDNA3.1 vector. Short hairpin (sh)RNA was used to downregulate HSC73 and HSP72.

Results: The activity of heat-inactivated DNA-PK recovered to about 50% of control during an additional incubation at 37?°C after heat treatment at 44?°C for 15?min in the presence of cycloheximide (which inhibits de novo protein synthesis). Maximal recovery was observed within 3?h of incubation at 37?°C after heat treatment. Constitutively expressed HSC73, which folds newly synthesized proteins, reached maximal levels 3?h after heat treatment using a co-immunoprecipitation assay with the Ku80 protein. Inhibiting HSC73, but not HSP72, expression with shRNA decreased the recovery of DNA-PK activity after heat treatment.

Conclusions: These results suggest that de novo protein synthesis is unnecessary for recovery of some heat-inactivated DNA-PK. Rather, it might be reactivated by the molecular chaperone activity of HSC73, but not HSP72.     

An updated review on pathophysiology and management of burning mouth syndrome with endocrinological,psychological and neuropathic perspectives

Burning mouth syndrome (BMS) is a chronic oro‐facial pain disorder of unknown cause. It is more common in peri‐ and post‐menopausal women, and sex hormone dysregulation is believed to be an important causative factor. Psychosocial events often trigger or exacerbate symptoms, and persons with BMS appear to be predisposed towards anxiety and depression. Atrophy of small nerve fibres in the tongue epithelium has been reported, and potential neuropathic mechanisms for BMS are now widely investigated. Historically, BMS was thought to comprise endocrinological, psychosocial and neuropathic components. Neuroprotective steroids and glial cell line–derived neurotrophic factor family ligands may have pivotal roles in the peripheral mechanisms associated with atrophy of small nerve fibres. Denervation of chorda tympani nerve fibres that innervate fungiform buds leads to alternative trigeminal innervation, which results in dysgeusia and burning pain when eating hot foods. With regard to the central mechanism of BMS, depletion of neuroprotective steroids alters the brain network–related mood and pain modulation. Peripheral mechanistic studies support the use of topical clonazepam and capsaicin for the management of BMS, and some evidence supports the use of cognitive behavioural therapy. Hormone replacement therapy may address the causes of BMS, although adverse effects prevent its use as a first‐line treatment. Selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs) may have important benefits, and well‐designed controlled studies are expected. Other treatment options to be investigated include brain stimulation and TSPO (translocator protein 18 kDa) ligands.     

beta2- and beta3-Adrenoceptor polymorphisms relate to subsequent weight gain and blood pressure elevation in obese normotensive individuals.

High blood pressure (BP) is a major determinant of cardiovascular events in obesity. The beta2- and beta3-adrenoceptor polymorphisms are associated with obesity and hypertension. In the present study, we examine the relationships of beta2- and beta3-adrenoceptor polymorphisms with further weight gain-induced BP elevation in obese subjects. Changes in BP, body weight, total body fat-mass, waist-to-hip ratio, plasma norepinephrine (NE) and leptin levels, and beta2(Arg16Gly)- and beta3(Trp64Arg)-adrenoceptor polymorphisms were measured periodically over a 5-year period in 55 entry obese (body mass index [BMI]> or =25.0 kg/m(2)) normotensive (BP<140/90 mmHg) men. BP elevation and weight gain were defined as > or =10% increases from entry levels over 5 years in mean BP or BMI. Obese subjects with weight gain, BP elevation or weight gain-induced BP elevation had higher frequencies of the Gly16 allele of Arg16GIy and Arg64 allele of Trp64Arg. Subjects carrying the Gly16 or Arg64 alleles had significantly greater total fat-mass and waist-to-hip ratio at entry and over a 5-year period compared to the subjects who did not carry these polymorphisms. Subjects carrying the Gly16 allele had similar levels of plasma NE, higher levels of plasma leptin and a lower slope of the regression lines between plasma leptin and NE levels. Those carrying the Arg64 allele had higher plasma NE levels at entry and over a 5-year period compared to the subjects without the Arg64 allele, but plasma leptin levels and slopes were similar. The findings demonstrate that the Arg64 allele of the beta3-adrenoceptor polymorphisms relates to weight gain-induced BP elevation accompanying high plasma NE (heightened sympathetic activity) in obese men. The Gly16 allele of the beta2-adrenoceptor polymorphisms links to weight gain-induced BP elevation associated with leptin resistance. beta2- and beta3-adrenoceptor polymorphisms could predict the future BP elevation and further weight gain-induced BP elevation in originally obese subjects.     

Application of cytopathology in a sensitivity test for anti-tumor agents. I. An experimental study

Although the human tumor clonogenic assay (HTCA) is extremely reliable in determining clinical correlations, it is a complicated process requiring considerable time in order to obtain results. Thus, an experimental study on cytopathologic observation (cytologic assay) and comparative evaluation between it and HTCA were performed in order to establish a more rapid and accurate drug sensitivity test. Materials included Colon 26, a cell line established in our department, malignant effusion and surgical specimens. In carrying out HTCA according to the Hamburger-Salmon method, the cell suspension samples following exposure to anti-tumor agents (MMC, L-PAM, ADM, CDDP) were cultivated in test tubes for 3-8 hours and stained by the Papanicolaou and Giemsa methods. According to Tokita's criteria, when cellular changes showed as nuclear pyknosis and nuclear destruction were found to have increased significantly in comparison with a control group, the cells were judged to be sensitive. Very similar and parallel results were obtained between HTCA and cytologic assay in this study, with a significant correlation. Cytologic assay was proved to be an easy, rapid and accurate method for testing drug sensitivity and its clinical application can be expected in the future.     

Kindling of the visual cortex in cats: comparison with amygdaloid kindling

Kindling of the primary visual cortex (VC) was compared with that of the amygdala in cats. VC kindling was basically similar to kindling of the amygdala in that daily electrical stimulation can lead to the development of a generalized convulsion in most subjects, a growth of afterdischarges in their configuration and duration, and a reduction of the afterdischarge threshold. The kindling response of the VC differed from that of the amygdala in a number of respects, i.e., a high afterdischarge threshold, a different pattern of behavioral seizure development, an abrupt growth of electroclinical seizures coincident with the onset of a generalized convulsion, an intersubject variability in seizure susceptibility, and a marked seizure instability. In VC kindling the afterdischarge propagation into the amygdala was not observed until the generalized convulsion developed, and the early involvement of afterdischarge was seen in the pulvinar, lateral geniculate body, and superior colliculus. These data suggest that a neural mechanism different from amygdaloid kindling may participate in VC kindling, and that the subcortical structures of the visual system are involved in the preferential pathway for a seizure generalization from the VC.     

Successful treatment of a patient with penetrating injury of the esophagus and brachiocephalic artery due to migration of Kirschner wires.

Pins and wires offer the simplest and most effective tools for managing bone fractures and dislocations. Migration of these devices within the chest is rare, but can cause serious problems. The spontaneous migration of Kirschner wires from the right clavicle to the mediastinum resulted in penetrating injury of the esophagus and pseudo-aneurysm of the brachiocephalic artery in an 84-year-old patient. Two Kirschner wires were removed via a vertical incision on the right shoulder without thoracotomy and the brachiocephalic artery was replaced with a Dacron graft.     

Early onset of ganciclovir-resistant cytomegalovirus infection in a lung-transplant recipient.

Ganciclovir resistance in cytomegalovirus (CMV) is an increasing problem in lung-transplant recipients with adverse clinical outcomes. We experienced the successful treatment of ganciclovir-resistant CMV infection in a lung-transplant recipient still receiving CMV prophylaxis. A 24-year-old woman with lymphangioleiomyomatosis underwent a living-donor lobar lung transplantation. She was a primary CMV mismatch (D+/R-) patient. She recovered from her postoperative complications, and was about to be discharged. However, she suffered ganciclovir-resistant CMV infection during prophylactic therapy. She was successfully treated with foscarnet, and is now alive without recurrence 18 months after surgery.     

Clinical study of estramustine phosphate disodium (Estracyt) on prostatic cancer--results of long-term therapy for 38 patients with prostatic cancer

Estramustine phosphate disodium (Estracyt) was used in the treatment of 38 patients with prostatic carcinoma for at least 1 year. Of these patients 37 patients were treated with Estracyt as primary treatment and 1 patient had been treated with another antiandrogenic therapy before the Estracyt treatment. Estracyt was given orally in a dose of 560 mg/day in divided oral doses. The clinical evaluation was done for the change of PAP, the relapse rate, the survival rate and the side effect. Among 22 cases which had shown abnormally high PAP values before the treatment started, the values decreased or normalized in 21 cases (95.5%) in the first year of administration of Estracyt. In 6 cases, however, the values increased again in the second year or later. Relapse was observed in 10 (26.3%) out of 38 cases. Relapse rate was 2.6%, 51.7%, and 51.7%, at the first, third, and fifth year, respectively. Survival rate was 97.4% at the first year, 88.5% at the third year, and 68.8% at the fifth year for the follow-up study. Side effects were observed in 14 (36.8%) out of 38 cases. The main side effect was gynecomastia. Gastro-intestinal disturbance and edema were also observed. However, there were only 2 cases (5.2%) in which administration of Estracyt had to be discontinued.