[Characteristics of bedridden elderly people living at home and in a hospital]

We compared bedridden elderly people living at home to others who were hospital inpatients. Questionnaires regarding medical status and care were returned by 85 of 116 people caring for a bedridden elderly person at home in Obu city, Aichi prefecture and by 62 of 64 nurses and family members caring for bedridden inpatients at Chubu National hospital. All subjects were at least 65 years old. The median age in both groups was 81 years, neither age distribution nor female sex predominance differed between both groups. The percentage of subjects with only one underlying disease was 62.5% among those living at home and 64.4% among inpatients. In both groups the most common disease was cerebrovascular disease (42.5% among those at home and 39.0% among inpatients), followed by dementia (31.3%), infirmity of old age (17.5%) and bone fracture (13.8%) among those at home, and by bone fracture (27.1%), dementia (20.3%) and infirmity of old age (16.9%) among inpatients. The median durations of bedridden status were 2 years and 3 months among those at home and 3 months among inpatients. The proportion of subjects bedridden for less than 6 months was greater among inpatients (p < 0.0001). The percentage who needed medical treatment was 60.0% among those at home and 67.7% among inpatients. The most common conditions for which drugs were taken were hypertension, dementia, chronic cerebrovascular dysfunction, and osteoporosis. Among inpatients, 54.8% were ambulatory before admission, 24.2% were almost completely bedridden, and 17.7% were completely bedridden. The most common cause rending the patients bedridden was infection (usually pneumonia). The degree of disability did not differ between groups. Decubitus ulcers were present in 25.9% of those at home and 17.7% of inpatients.

Morphological and morphometric features of the deformed cervical and caudal vertebrae in a new mutant knotty-tail (knt/knt) mouse

Morphological and morphometric examinations were conducted on skeletons of knotty-tail (knt/knt) mouse, a new autosomal recessive mutant. The knt/knt mice have short and knotty tails. The number of caudal vertebrae is reduced and their deformed caudal vertebrae show no parallelism between the epiphyseal planes and no osseous fusions. Morphological changes, except for the caudal vertebrae, are confined to the neural arches of the axis in knt/knt mice. As for the tail anomaly, the knt gene seems to have the same action as the tk gene, but knt/knt mice differ from other strains with respect to cervical morphology. The morphometry of the caudal vertebrae revealed that knt/knt mice have a discontinuous and lower ratio of width to length after their 6th caudal vertebra. The morphometry also revealed that knt/knt mice have 1) broadened cervical vertebrae in the transverse direction, 2) thickened ventral lamina of the 6th cervical vertebra and 3) shortened and broadened ventral tuberculum of the atlas. From these results, the knt/knt mouse was considered to be a new pleomorphic mutant.

[Study of bacterial flora in the oral cavity and stomach of elderly patients receiving nasogastric tube feeding]

To investigate the significance of oropharyngeal flora and gastric flora in elderly patients receiving nasogastric tube feeding, throat secretions and gastric aspirates were cultured and the pH of the latter was measured. Of 116 bacterial isolates from throat secretions of 27 elderly patients, 30 were beta-streptococci and 28 were Pseudomonas aeruginosa. Bacteria isolated from gastric aspirates numbered 86 and 24 (27.9%) of them were the same species as those found in the throat secretions. Patients with gastric pH were below 3.5 had significantly lower concentrations of gram-negative bacili in gastric aspirates. We also studied oropharyngeal flora in 33 elderly patients who were admitted to Nagoyashi Koseiin Geriatric Hospital. The major bacterial isolates from throat swabs of bedridden patients were gram-negative bacilli and beta-streptococci, especially group B streptococci (GBS). We measured the level of antibody to GBS in these patients. Those from whom GBS were isolated had high titers. These results suggest that in elderly patients receiving enteral nasogastric) tube feeding, large numbers of bacteria colonize the oral cavity and stomach. The measurement of type-specific antibody to GBS may be useful in managing such patients.

The E6-Ap ubiquitin-protein ligase (UBE3A) gene is localized within a narrowed Angelman syndrome critical region

Angelman syndrome (AS) and Prader-Willi syndrome (PWS) are distinct clinical phenotypes resulting from maternal and paternal deficiencies, respectively, in human chromosome 15qll-q13. Although several imprinted, paternally expressed transcripts have been identified within the PWS candidate region, no maternally expressed gene has yet been identified within the AS candidate region. We have developed an integrated physical map spanning the PWS and AS candidate regions and localized two breakpoints, including a cryptic t(14;15) translocation associated with AS and a non-AS 15q deletion, which substantially narrow the AS candidate region to approximately 250 kb. Mapping data indicate that the entire transcriptional unit of the E6-AP ubiquitin-protein ligase (UBE3A) gene lies within the AS region. The UBE3A locus expresses a transcript of approximately 5 kb at low to moderate levels in all tissues tested. The mouse homolog of UBE3A was cloned and sequenced revealing a high degree of conservation at nucleotide and protein levels. Northern and RT-PCR analysis of Ube3a expression in mouse tissues from animals with segmental, paternal uniparental disomy failed to detect substantially reduced or absent expression compared to control animals, failing to provide any evidence for maternal-specific expression from this locus. Recent identification of de novo truncating mutations in UBE3A taken with these observations indicates that mutations in UBE3A can lead to AS and suggests that this locus may encode both imprinted and biallelically expressed products.

Familial lethal inheritance of a mutated paternal gene in females causing X-linked ornithine transcarbamylase (OTC) deficiency

A Leu148Phe substitution of the ornithine transcarbamylase (OTC) gene was identified in a 2-year-old girl with OTC deficiency (14% of control). Her two elder sisters died in childhood of hyperammonemia, and the patient also died of OTC deficiency. Enzyme activity in Cos1 cells transfected by the mutant cDNA was undetectable, thereby indicating a definite pathogenic mutation. Familial gene analysis showed that the mother had wild-type OTC alleles on both X-chromosomes and the father was a mosaic for the mutant allele in his lymphocytes and spermatozoa. This clinical case shows that a somatic and germline mosaicism for a single-gene disorder led to an unusual pattern of X-linked inheritance in the family, and all three daughters in the family died of OTC deficiency. The possibility that inherited factors will lead to skewed X-inactivation needs to be considered.

Lecithin:retinol acyltransferase and retinyl ester hydrolase activities are differentially regulated by retinoids and have distinct distributions between hepatocyte and nonparenchymal cell fractions of rat liver

The cellular distribution of enzymes that esterify retinol and hydrolyze retinyl esters (RE) was studied in liver of vitamin A-sufficient, -deficient, and deficient rats treated with retinoic acid or N-(4-hydroxyphenyl)-retinamide. Livers were perfused and cell fractions enriched in hepatocytes, and nonparenchymal cells were obtained for assays of RE and enzyme activity. The specific activity of lecithin:retinol acyltransferase (LRAT) was approximately 10-fold greater in the nonparenchymal cell than the hepatocyte fraction from both vitamin A-sufficient and retinoid-treated rats. Total RE mass, newly synthesized [3H]RE and LRAT activity were positively correlated in liver and isolated cells of both normal (P < 0.0001) and retinoid-treated rats (P < 0.0002). In nonparenchymal cells, these three constituents were nearly equally enriched as evaluated by their relative specific activity values (RSA, defined as the percentage of recovered activity divided by the percentage of recovered protein), which were each significantly greater than 1.0, with values of 4.3 for total RE mass (P < 0.05), 3.6 for newly synthesized [3H]RE (P < 0.01) and 3.8 for LRAT activity (P < 0.01). In contrast, the specific activities of neutral and acid bile salt-independent retinyl ester hydrolases (REH) did not vary with vitamin A status, and their RSA values were close to 1.0 in both hepatocytes and nonparenchymal cells. These data show that LRAT and REH are differentially regulated by retinoids and that these enzymes also differ in their spacial distribution between liver parenchymal and nonparenchymal cells.

The R40H mutation in a late onset type of human ornithine transcarbamylase deficiency in male patients

Ornithine transcarbamylase (OTC) deficiency is an X-linked trait and is one of the most frequent of the inherited urea cycle enzyme deficiencies. Most male patients with OTC deficiency develop a hyperammonemic crisis and die in the neonatal period or in early infancy. In contrast to those patients, in some male patients the disease first becomes overt in adolescence or during the reproductive age period. In the present report, we describe six such male patients who first developed clinical signs at ages ranging from 6 to 58 years, all of whom came from a limited area of the northern part of Kyushu Island in southern Japan. The mutation analysis disclosed a R40H mutation in exon 2 of the OTC gene in each of these patients. Transmission of this mutant gene through paternal lineage as well as through maternal lineage was documented in one family. The levels of mRNA of the mutant OTC gene expressed in transfected Cos 1 cells and in the liver tissue obtained by biopsy in one patient were both similar to those of the wild-type gene. The activity of the mutant OTC was, however, decreased to a level of 28% of the wild-type OTC, and the levels of the mutant OTC protein expressed in Cos 1 cells were decreased, as assessed by western blot analysis. Apparent Km values of the mutant enzyme for ornithine (1.1 mM) and carbamylophosphate (2.0 mM) were similar to those of the wild-type enzyme. Both enzymes gave similar pH-dependency profiles, giving a maximal activity at pH 7.8-7.9. Activity of wild-type OTC expressed in Cos 1 cells did not change after five cycles of freezing and thawing, whereas that of the mutant OTC decreased to 17% by this treatment. These results suggest that deficiency is due to inactivation of the mutant OTC under certain conditions.

De novo truncating mutations in E6-AP ubiquitin-protein ligase gene (UBE3A) in Angelman syndrome

Angelman syndrome (AS) is associated with maternal deletions of human chromosome 15q11-q13 and with paternal uniparental disomy for this region indicating that deficiency of an imprinted, maternally expressed gene within the critical interval is the likely cause of the syndrome. Although the gene for E6-AP ubiquitin-protein ligase (UBE3A) was mapped to the critical region for AS, evidence of expression from both parental alleles initially suggested that it was an unlikely candidate gene for this disorder. Because attempts to identify any novel maternally expressed transcripts were unsuccessful and because the UBE3A gene remained within a narrowed AS critical region, we searched for mutations in UBE3A in 11 AS patients without known molecular defects (large deletion, uniparental disomy, or imprinting mutation). This analysis tested the possibility that deficiency of an undefined, maternally expressed transcript or isoform of the UBE3A gene could cause AS. Four mutations were identified including a de novo frameshift mutation and a de novo nonsense mutation in exon 3 and two missense mutations of less certain significance. The de novo truncating mutations indicate that UBE3A is the AS gene and suggest the possibility of a maternally expressed gene product in addition to the biallelically expressed transcript. Intragenic mutation of UBE3A in AS is the first example of a genetic disorder of the ubiquitin-dependent proteolytic pathway in mammals. It may represent an example of a human genetic disorder associated with a locus producing functionally distinct imprinted and biallelically expressed gene products.

Suppressed alloreactivity and mixed chimerism in rats with accepted cardiac allografts by intrathymic injection of donor bone marrow cells

Intrathymic injection of donor bone marrow cells (ITBMCs) at the time of transplantation and treatment with antilymphocyte serum (ALS) permitted the indefinite survival of Brown Norway (BN, RT1n) rat heart grafts in 6 out of 8 Lewis (LEW, RT1l) rat recipients, LEW recipients with long-surviving BN heart grafts (LSGs) also accepted additional BN heart grafts without further immunosuppression, though they rejected Piebald Virol Glaxo (PVG, RT1c) rat heart grafts in the usual fashion. In the in vitro study, the proliferative response of the lymphocytes from LEW recipients with LSGs remained suppressed when they were stimulated by BN spleen cells, but not when stimulated by PVG cells. Bone marrow cells (BMCs) from LEW rats with LSGs showed strong, nonspecific, suppressive effects on the proliferative response in the mixed lymphocyte culture reaction, suggesting that one of the possible explanations for tolerance might be the involvement of a suppressor mechanism.

Induction of gammadelta T cells during acute murine infection with Toxoplasma gondii

The importance of the host gammadelta T cell response to microbial pathogens is not yet fully understood. We report that inbred mice infected with T. gondii developed a gammadelta T cell proliferative response to parasite Ag. Mice depleted of either the alphabeta or gammadelta TCR were found to be significantly more susceptible to infection than the parent mouse strain. Proliferation of gammadelta T cells was observed in mice deficient in the TCR-alphabeta in response to UV-irradiated parasites. These T cells lyse parasite-infected syngenic macrophages. Adoptive transfer of these gammadelta T cells into beta2 microglobulin-deficient mice that have been depleted of both CD4+ and NK cells prolongs survival against acute parasite challenge when compared with nontransferred controls. The gammadelta T cells isolated from infected alpha -/- mice express a 10-fold increase in mRNA and produce high titers of IFN-gamma. These data suggest that gammadelta T cells may play an important role in the early host response to infection with T. gondii.

Induction of gammadelta T cells during acute murine infection with Toxoplasma gondii

The importance of the host gammadelta T cell response to microbial pathogens is not yet fully understood. We report that inbred mice infected with T. gondii developed a gammadelta T cell proliferative response to parasite Ag. Mice depleted of either the alphabeta or gammadelta TCR were found to be significantly more susceptible to infection than the parent mouse strain. Proliferation of gammadelta T cells was observed in mice deficient in the TCR-alphabeta in response to UV-irradiated parasites. These T cells lyse parasite-infected syngenic macrophages. Adoptive transfer of these gammadelta T cells into beta2 microglobulin-deficient mice that have been depleted of both CD4+ and NK cells prolongs survival against acute parasite challenge when compared with nontransferred controls. The gammadelta T cells isolated from infected alpha -/- mice express a 10-fold increase in mRNA and produce high titers of IFN-gamma. These data suggest that gammadelta T cells may play an important role in the early host response to infection with T. gondii.

Molecular cloning, tissue distribution, and chromosomal localization of human cationic amino acid transporter 2 (HCAT2)

Human cationic amino acid transporter 2 (HCAT2) was isolated from a human intestine cDNA library. The nucleotide sequence of the coding region predicts a 658-amino-acid protein with a calculated molecular weight of 71,669. As 91% of the residues are identical with those of the mouse cationic amino acid transporter 2 (MCAT2), HCAT2 seems to be a human counterpart of MCAT2. We found no isoform as was present in MCAT2. In Northern blot analysis, a single (9.0 kb) HCAT2 mRNA transcript was present in various human tissues. The highest level of expression was observed in skeletal muscle and the lowest level in the kidney. Hydropathy plots indicated that the translated protein is predicted to have 14 transmembrane domains with three potential N-glycosylation sites. Two patients with lysinuric protein intolerance (MIM No. 222700) were analyzed for HCAT2 cDNA but no mutation was detected. The HCAT2 gene was assigned to human chromosome 8p21.3-p22.

[The period of termination of nasal symptoms in Japanese cedar pollinosis patients and factors participating in the termination of symptoms]

We investigated when nasal symptoms in 219 patients with cedar pollinosis terminated in 1995. To study factors participating in symptom termination, we examined the rate of positive CAP RAST for antigens other than Japanese cedar in 121 patients, as well as nasal hypersensitivity to histamine and the number of basophilic cells or eosinophils in the surface layer of nasal mucosa in 53 patients before, during and after the Japanese cedar-cypress season. There were peak periods for the termination of nasal symptoms between the end of April and early May. Seventy percent of the patients had symptoms not only during the Japanese cedar season but also during the Japanese cypress season, and 23% of the patients had symptoms that persisted after the Japanese cypress season ended. In the group of patients with persistent symptoms after May date group), the rate of positive CAP RAST for tree pollens other than Japanese cedar or cypress was higher than that in the early group of patients. Moreover in the late group, nasal hypersensitivity to histamine after the season ended remained significantly higher than that in the early group of patients. However, the number of basophilic cells or eosinophils after the season ended showed no significant difference between the early and late groups. In conclusion, sensitization for tree pollens other than Japanese cedar or cypress and nasal hypersensitivity after the season were important factors participating in the termination of nasal symptoms.

[Study of androgen receptor expression and neuronal vulnerability in X-linked spinal and bulbar muscular atrophy]

X-linked spinal and bulbar muscular atrophy (SBMA), a rare adult onset form of motor neuron disease, is clinically characterized by slowly progressive muscle weakness and atrophy, and endocrinopathy such as gynecomastia, testicular atrophy and oligospermia. Androgens are known to play an important role in motor neuron growth, development and regeneration. The genetic mutation of androgen receptor (AR) gene in SBMA has been disclosed and thought to lead to degeneration of lower motor neurons. However, the mechanism of neuronal death and the basis for the regional specificity of neuropathology observed in SBMA are not clear. At first, we proved the existence of androgen receptor (AR) in the motor neurons of the rat spinal cord by the immunohistochemical stain and Western blotting. The possibility that AR protein in spinal cord is expressed in tissue-specific form is proposed, being different from other androgen-dependent tissue. Northern blotting data showed that AR is expressed in not only rat spinal cord but also cerebrum and cerebellum, which are spared in SBMA. Then, specimens from 2 SBMA patients were examined and compared with those from normal controls (n = 4). AR was widely expressed in central nervous system. Anterior horn cells, which are severely affected in SBMA, were stained intensely. Even the remaining atrophic motor neurons in SBMA had AR. To our interest, the neurons of cranial nerves III, IV, VI, dentate nucleus, posterior horn and Onufrowicz nucleus etc., which are spared in SBMA, contained AR moderately. These data did not show any difference between SBMA and controls. Our immunohistochemical study showed that not only the neurons affected in SBMA but the unaffected in this disease process express AR. The question why motor neurons are selectively involved in SBMA if AR is present in almost neurons should further be clarified.

[Extracorporeal shock wave lithotripsy monotherapy for a renal stone in a 15-month-old child]

A 15-month old child visited our hospital with the chief complaint of macroscopic hematuria. Intravenous pyelography (i.v.p.) revealed a right renal stone (20 x 18 mm) with hydronephrosis and hydroureter. Extracorporeal shock wave lithotripsy (ESWL) was performed twice using a SEMENSE LITHOSTER for the stone. A cardboard and a towel were used to protect the lung and for focusing the shock waves. We achieved complete stone clearance with the ESWL monotherapy. I.v.p. and voiding cystography (VCG) after ESWL revealed disappearance of right hydronephrosis and hydroureter and no reflux. As of June 1995, his general condition is good and there are no recurrent stones.

Morphogenesis of degenerative changes predisposing dogs to rupture of the cranial cruciate ligament

The cranial cruciate ligaments (CCL) of 13 dogs with clinical signs of CCL rupture and those of 22 clinically healthy young beagle dogs for laboratory use were examined histopathologically and immunohistopathologically. The most constant changes at an early stage of degenerating ligament tissue in affected dogs were nuclear enlargement and perinuclear halo formation of fibrocytes followed by chondroid metaplasia. These changes were also frequent in apparently healthy young beagles kept under laboratory conditions. PAS and alcian blue positive substance accumulated around activated fibrocytes and within perinuclear halos. S-100 protein was also positive in these cells preceding the morphological change of chondroid metaplasia. Increased mitotic figures and Ki-67 positive cells showed the proliferating nature of these cells at a later stage. Alteration of extracellular matrices from dense collagen fiber type to those of cartilage tissue seemed to predispose dogs to rupture of the CCL along with a degradation in collagen fiber of the primary bundles. Collagen fiber bundles with a parallel fibrillar array never formed in the CCL with degraded primary bundles, whereas activated fibrocytes constantly underwent chondroid metaplasia. The pathogenic mechanism underlying chondroid metaplasia was thought to be nonspecific and attributable to an essential property of activated fibrocytes in the mature tendon tissue.

[Methods of evaluating airway inflammation]

Airway inflammation is a feature of bronchial asthma and can be quantified invasively with bronchial mucosal biopsy and bronchoalveolar lavage. The induction of sputum by the inhalation of hypertonic saline however is safer and more noninvasive when compared with such methods. Evidence of airway inflammation may be revealed by examining hypertonic saline-induced sputum for eosinophils, cytokines and eosinophil cationic protein. There is a clear need however to develop further noninvasive discriminant measurement of airway inflammation.

N-(4-hydroxyphenyl)-retinamide increases lecithin:retinol acyltransferase activity in rat liver

N-(4-Hydroxyphenyl)-retinamide (4-HPR; Fenretinide) is a synthetic retinoid which is undergoing investigation as a cancer chemopreventive agent. However, 4-HPR alters vitamin A kinetics and reduces the concentration of plasma retinol. We have conducted studies to examine the effects of 4-HPR on the activity of the enzyme lecithin:retinol acyltransferase (LRAT). This enzyme is implicated in the absorption and storage of vitamin A and is regulated, in liver, by vitamin A nutritional status. To determine whether 4-HPR, like retinoic acid, is able to induce liver LRAT activity, vitamin A-deficient rats having negligible liver LRAT activity were treated with single doses of 4-HPR (0.02-2.5 mg) and liver homogenates were assayed for LRAT activity using 3H-retinol bound to the cellular-retinol binding protein, CRBP, as substrate. Treatment with 4-HPR resulted in a dose- and time-dependent increase in liver LRAT activity which reached a maximum at 24 h. The activity of LRAT assayed in vitro and of hepatic 3H-retinyl ester content determined after an in vivo pulse of 3H-retinol were highly correlated (r = 0.802, P < 0.0002). When vitamin A-sufficient rats were fed a 4-HPR-supplemented diet for 30 d, LRAT activity differed significantly from control values in the liver (P < 0.0001) but not the small intestines. Changes in hepatic retinol metabolism which favor the esterification of vitamin A may be related to the mechanism by which 4-HPR alters vitamin A kinetics in vivo.