Heterozygote effects in dreher mice

The dreher mutation (gene symbol: dr) is an autosomal recessive mutation located on chromosome 1 of the mouse. Homozygous dreher mice (dr/dr) are ataxic, have a white belly spot, a short-tail, inner ear and skeletal malformations, and a variety of CNS abnormalities. Recently in our dreher colony (the drsst-J allele on a B6C3Fe background), we noticed mice with one or more white belly spots typical of drsst-J/drsst-J mice but which were non-ataxic and had a normal tail length; wild-type mice (+/+) of the same genetic background do not have simialr belly spots. Results of three breeding experiments indicate that a new mutation had not occurred, but rather that the spotted, non-ataxic mice are heterozygous dreher mice (drsst-J/+). Histological examination showed that drsst-J/+ mice have abnormalities in the hippocampal formation that are qualitatively similar to those found in drsst-J/drsst-J mice. Most frequently there is an increase in the number of pyramidal cells in CA3 and a marked thickening of the pyramidal cell layer. In contrast to dreher homozygotes the cerebellum appears to have a normal foliation pattern and no discernible laminar abnormalities. Thus, both breeding experiments and histological examination indicate that drsst-J is semidominant. We speculate that drsst-J is a "loss of function" mutation, but, in any event, the presence of phenotypic abnormalities in drsst-J/+ mice may be useful in identifying the primary developmental defect in dreher mice.     

Proffered opinion forum medical decision making, impact on laboratory tests

Raising medical expenditure is a universal problem. The Japanese government started taking measures not to increase medical expenses in the recent years. Laboratory tests are no exception. Therefore we as clinical pathologists have reevaluated laboratory tests from the primary care situations to more advanced stages of clinical medicine. As the first step, we formed a subcommittee to effective by utilize laboratory tests and agreed to establish the "essential lab tests". Essential lab tests are made of qualitative bed side tests (type I) and slightly advanced tests (type II) and these tests are to be done on every patient at their first clinic visit. These tests are also to be performed parallel to physical examination and history-taking. The results revealed 50% and 90% positivities on the type I and type II tests, which indicate rather effective means for making an initial impression.     

Design, synthesis, structure-activity relationships, and biological characterization of novel arylalkoxyphenylalkylamine sigma ligands as potential antipsychotic drugs

sigma Receptor antagonists may be effective antipsychotic drugs that do not induce motor side effects caused by ingestion of classical drugs such as haloperidol. We obtained evidence that 1-(2-dipropylaminoethyl)-4-methoxy-6H-dibenzo[b,d]pyran hydrochloride 2a had selective affinity for sigma receptor over dopamine D2 receptor. This compound was designed to eliminate two bonds of apomorphine 1 to produce structural flexibility for the nitrogen atom and to bridge two benzene rings with a -CH2O- bond to maintain the planar structure. In light of the evidence, N, N-dipropyl-2-(4-methoxy-3-benzyloxylphenyl)ethylamine hydrochloride 10b was designed. Since compound 10b had eliminated a biphenyl bond of 6H-dibenzo[b,d]pyran derivative 2a, it might be more released from the rigid structure of apomorphine 1 than compound 2a. The chemical modification of compound 10b led to the discovery that N, N-dipropyl-2- [4-methoxy-3-(2-phenylethoxyl)phenyl]ethylamine hydrochloride 10g (NE- 100), the best compound among arylalkoxyphenylalkylamine derivatives 3, had a high and selective affinity for sigma receptor and had a potent activity in an animal model when the drug was given orally. We report here the design, synthesis, structure-activity relationships, and biological characterization of novel arylalkoxyphenylalkylamine derivatives 3.     

Automatic detection of rapid eye movements by discrete wavelet transform

In order to detect rapid eye movements (REM) automatically, the Discrete Wavelet Transform was applied to each 8-s segment of electrooculogram (EOG) data for 30 min of 8 h of normal sleep. The Haar function was used as an analysing wavelet because this function is similar to the REM waveform. By shifting the phase of the analysing wavelet by pi/4 of the function, 96% of REM could be detected. The artifacts caused by body movements could be detected simultaneously by this method. Computing time required for the detection of REM was only 11 s for 30 min EOG data.     

Clinical significance of interstitial collagen deposition at the invading edge in oral cancer: Immunohistochemistry for type I collagen

Background Changes in interstitial collagen in human oral cancer have not yet been fully studied. We examined the relationship between the degree of interstitial collagen deposition at the invading edge of the tumor, and the clinical and pathologic findings in oral squamous cell carcinoma. We also investigated the therapeutic implication of the changes in distribution patterns of collagen deposition by comparing biopsy specimens and surgical specimens. Methods Immunohistochemical staining was performed by the streptavidin-biotin method using antibody against human type I collagen for visualizing interstitial collagen in 50 biopsy and 45 surgical specimens. Results Carcinomas with scanty interstitial collagen in biopsy specimens tended to have highly malignant characteristics. Large carcinomas with scanty deposition both in biopsy and surgical specimens were likely to have positive resection margins in spite of radical surgery. Conclusion Immunostaining patterns for type I collagen of oral squamous cell carcinomas can provide information of importance in determining safe resection margins.     

Chronic Pulmonary Disease Caused by Tsukamurella toyonakaense

Unidentified Mycobacterium species are sometimes detected in respiratory specimens. We identified a novel Tsukamurella species (Tsukamurella sp. TY48, RIMD 2001001, CIP 111916^T), Tsukamurella toyonakaense, from a patient given a misdiagnosis of nontuberculous mycobacterial pulmonary disease caused by unidentified mycobacteria. Genomic identification of this Tsukamurella species helped clarify its clinical characteristics and epidemiology.     

Clinical Characteristics Associated with the Development of Diabetic Ketoacidosis in Patients with Type 2 Diabetes

Objective This study analyzed the clinical and laboratory parameters that might influence the clinical outcomes of patients with type 2 diabetes who develop diabetic ketoacidosis (DKA), which has not been well investigated. Methods We reviewed the clinical and laboratory data of 158 patients who were hospitalized due to DKA between January 2006 and June 2019 and compared the data of patients stratified by the type of diabetes. In addition, the patients with type 2 diabetes were subdivided according to age, and their clinical and laboratory findings were evaluated. Results Patients with type 2 diabetes had a longer symptom duration associated with DKA, higher body mass index (BMI), and higher C-peptide levels than those with type 1 diabetes (p＜0.05). Among patients with type 2 diabetes, elderly patients (≥65 years old) had a longer duration of diabetes, higher frequency of DKA onset under diabetes treatment, higher effective osmolarity, lower BMI, and lower urinary C-peptide levels than nonelderly patients (＜65 years old) (p＜0.05). A correlation analysis showed that age was significantly negatively correlated with the index of insulin secretory capacity. Conclusion Patients with DKA and type 2 diabetes had a higher BMI and insulin secretion capacity than those with type 1 diabetes. However, elderly patients with type 2 diabetes, unlike younger patients, were characterized by a lean body, impaired insulin secretion, and more frequent DKA development while undergoing treatment for diabetes.