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Biomedical subjects

A Hori

Publications and source records attributed to A Hori.

At least 55 records · Page 3Linked to original sources
PubMed1999

Immunohistochemical survey of migration of human anterior pituitary cells in developmental, pathological, and clinical aspects: a review.

Developmentally pathological conditions of the anterior pituitary cells include failed separation of the primary pituitary gland into sellar and pharyngeal ones, ectopic migration into the subarachnoid space, and basophil invasion into the posterior lobe although the last is a physiological phenomenon with pathological potentiality in certain circumstances. Pituitary primordium appears at about 4 weeks of gestation. One of the causes of the pituitary gland agenesis may be a formation of the primary hypothalamic ganglionic hamartoma just at the time of occurrence of the pituitary primordium, as analyzed in cases of Pallister-Hall syndrome. A double pituitary in a single individual is a rare malformation. Its pathogenesis is considered as a result of notochordal anomaly. In the 8th gestational week, the primary pituitary gland separates into sellar and pharyngeal parts. The disturbance of this histogenesis results in a rare pituitary malformation, a "pharyngosellar pituitary." Despite the failed separation in this case, differentiation of the pituitary cells proceeds and the hormone production of this malformed pituitary gland can be displayed immunohistochemically. In this case, the distribution of the different hormone producing cells was atypical, particularly in those of gonadotropic hormones and ACTH. Life-long existence of the pharyngeal pituitary is a normal anatomical state in humans. Cell differentiation (hormone production) in the pharyngeal pituitary occurs about 4-10 weeks later than in the sellar pituitary. In pharyngeal pituitary, all kinds of adenohypophyseal hormones are produced. Extracranial pituitary adenomas (with intact sellar pituitary), exclusively found in the nasopharynx, sphenoid sinus, and clivus, may occur from the pharyngeal pituitary while another tumorigenesis can develop from the residual tissue fragment in the craniopharyngeal canal. The "overshoot" of the adenohypophyseal cell migration in the distal part of the sellar pituitary is frequently observed in the leptomeninges of the peri-infundibular or peri-hypothalamic region as ectopic pituitary cell clusters that are apparently independent of the pars tuberalis. It is suggested that these cells, frequently found in "normal" individuals, may be one of the possible origins of the intracranial ectopic pituitary adenomas. However, the reason why a majority of the reported intracranial ectopic pituitary tumors are ACTH-adenomas remains unexplained, since the ectopic cells, found in "normal" individuals, consist of fairly different hormone-producing cells. A further enigmatic phenomenon is a "basophil invasion." ACTH-positive cells invade from the pars intermedia into the posterior lobe of the pituitary. This invasion increases in intensity and frequency according to increase in age. However, the invasion of ACTH cells is observed as early as in the fetal life. The invasive cells display occasionally cell atypia as well as mitotic activity. The origin of extremely rare pituitary adenomas inside the posterior lobe can be explained by the existence and proliferative activity of basophil invasion.

Adenoma↗
PubMed1999

Neuronal impairment of adult moyamoya disease detected by quantified proton MRS and comparison with cerebral perfusion by SPECT with tc-99m HM-PAO: a trial of clinical quantification of metabolites.

We evaluated neuronal impairment of adult moyamoya patients by proton magnetic resonance spectroscopy (MRS) and cerebral perfusion scintigraphy. After evaluating two methods for compensating relaxation times, we selected a long TR, short TE sequence to achieve better reproducibility. The cerebral blood flow (CBF) value was measured by scintigraphy following the method of quantification reported in the previous literature. N-acetyl aspartate (NAA) concentrations and CBFs value were decreased statistically (P < 0. 05) compared with those of the age-matched normal controls. However, the decreased rate of NAA concentration was changed more than the CBF value, and no linear correlation was found between the two values. We considered that the NAA concentration was not always correlated with that of the present cerebral perfusion. The NAA concentration showed a more dispersive distribution in patients than in controls, indicating a large individual variation in neuronal impairment. We concluded that proton MRS may provide useful information about neuronal impairment in individual patients. J. Magn. Reson Imaging 1999;10:124-129.

Adult↗
PubMed1999

Thirty-six cases of obturator hernia: does computed tomography contribute to postoperative outcome?

Obturator hernia is relatively rare and occurs mostly in elderly, thin, multiparous women. Recent reports have highlighted the importance of pelvic computed tomography (CT) for the preoperative diagnosis. Thirty-six patients with an obturator hernia operated in our hospital were divided retrospectively into two groups (group A: 18 operations from 1973 to 1986, before we used CT; group B: 18 CT cases from 1987 to 1995). Preoperative diagnoses, operative procedures, and postoperative course were reviewed. No statistically significant differences were found between groups A and B in terms of patient characteristics. Rates of accurate preoperative diagnoses were significantly higher in group B: 39% (7/18) in group A and 78% (14/18) in group B (p = 0.018). The intraoperative findings, occurrence of postoperative complications, and overall mortality rates were similar between the two groups. There were four postoperative deaths (mortality rate 11%). Three of four patients who died had panperitonitis because of small bowel perforation. The correct preoperative diagnosis of obturator hernia was facilitated by CT of the pelvis, but it has no impact on patient outcome. Early diagnosis and surgical intervention are essential for this rare entity.

Aged↗
PubMed1999

Pharyngeal pituitary: development, malformation, and tumorigenesis.

The development of the pharyngeal pituitary (PhP) in the fetal period was morphologically and, for the first time, immunohistochemically examined. PhP, found in every individual, begins its hormone production at the 17-18th week of gestation, that is, 4-8 weeks later than that of sellar pituitary (SP). Only 1 of 25 examined fetuses without any stigmata of developmental anomalies showed a residual pituitary fragment in the craniopharyngeal canal (craniopharyngeal pituitary, CPhP). An adult case of a rare clivus pituitary adenoma that we examined is demonstrated in discussing its relationship to PhP. Extracranial ectopic pituitary adenomas in the literature describe an exclusively sphenoid sinus/nasopharyngeal/clivus location of the tumor. Their location corresponded exactly with that of PhP, so that the origin of the tumors can be reasonably speculated as PhP, although another origin, e.g., CPhP, can not be excluded. A variety of malformations of PhP, although very rare, have been described for the fist time during the systemic examination of 16 fetuses with different cranioneural malformations, such as agenesis, unseparated PhP from SP (pharyngosellar pituitary), fragmentation, and residual pituitary tissue in the open craniopharyngeal canal. However, developmental anomaly of PhP was not specifically associated with cranioneural malformations except in cases of chromosomal aberrations. The hormone production in PhP in malformation cases tended to be retarded. Absence of SP was recorded in 50% of anencephalics in the literature; however, PhP was identified in all anencephalics in our series, independent of the existence of SP. This supports the opinion that agenesis of SP in anencephalics seems to be false information.

Adenoma↗
PubMed1999

Symptom classification of schizophrenia changes with the duration of illness.

Our starting hypothesis was that schizophrenic symptomatology changes over time. This hypothesis explains conflicting reports on schizophrenic symptom structures as a consequence of different durations of illness in the samples studied to date. Therefore a sample of 258 schizophrenic in-patients (with ICD-10 diagnoses F20) was categorized according to illness duration. A factor analysis was performed on the 8 items of the Manchester Scale for three subgroups (duration < 10 years, 10> or =20 years and > or = 20 years). For those patients whose illness duration was less than 10 years, 'formal thought disorder' was not related to any other mental state, whereas for those whose duration was 10 years or longer, it was correlated with 'negative symptoms'. In the < 10 years group, 'anxiety and depression syndrome' and 'positive symptoms' formed one complex, but these symptoms were separated into two distinct syndromes in the > or = 20 years group. Thus we were able to demonstrate that the classification of symptoms changes with increasing duration of illness.

Adolescent↗
PubMed1999

Criteria defining refractory schizophrenia.

To date there has been no agreement with regard to the criteria that define refractory schizophrenia. In this study, we intended to clarify the criteria which psychiatrists use to judge schizophrenic patients as being refractory in Japan. Based on 258 schizophrenic in-patients (ICD-10) and their likelihood of discharge, level of psychosocial functioning, mental state and use of medication, the common features of patients who are viewed as non-dischargeable because of their severe mental state, compared to those of dischargeable patients, were extracted and used as the criteria. The criteria proposed necessitate (i) diagnosis of schizophrenia by standard operational criteria, (ii) continuous hospitalization for at least the past 2 years, (iii) a level of psychosocial functioning of < or = 40 as measured by the Global Assessment Scale, and (iv) an intensity score of 'marked' or 'severe' on at least three of the six Manchester Scale items (flattened affect, psychomotor retardation, delusions, hallucinations, incoherence of speech and poverty of speech).

Adult↗
PubMed1998

Retroperitoneal ectopic neural mass: "abdominal brain"--presentation of two cases and proposal of classification of paraneuraxial neural ectopia.

An encapsulated mass of brain tissue was found in the retroperitoneum of a fetus of gestational week 15 and a boy of age 3 years. The masses possessed fibrous tissue that bound them to the spine and intraspinal connective tissue, respectively, but there was no evidence of direct continuity of the ectopic brain tissue with the normal central nervous system. There was no dysraphism. In our fetal case, possible Foix-Alajouanine anomaly was additionally found. The ectopic neural tissue in the retroperitoneal region may be termed "abdominal brain." In the literature, an identical state has been described in the head (paracranial region) but there are no other records of the paraspinal region. Despite the different locations of the masses (head/paracranial or retroperitoneum/paraspinal), these ectopic brain masses should belong to the same disorder spectrum of the paraneuraxial neural ectopia, a new concept.

Cell Differentiation↗
PubMed1998

Leiomyosarcoma of the inferior vena cava. Resection and reconstruction of the renal vein using the gonadal vein.

We succeeded in surgically resecting a leiomyosarcoma of the inferior vena cava (IVC), which originated at the confluent portion of the right renal vein (RRV), together with the IVC and RRV, and also were able to preserve the right kidney by reconstructing the RRV with end-to-end anastomosis using the right gonadal vein. A good blood flow of the reconstructed RRV was thereafter confirmed by color Doppler ultrasonography, and the renal function was also satisfactory. This new procedure, a reconstruction of the RRV using the gonadal vein, has not been previously reported, but is considered to be an easy and effective method which enables the surgeon to preserve the normal right kidney.

Aged↗
PubMed1998

Intraportal stent placement combined with right portal vein embolization against advanced gallbladder carcinoma.

We describe herein the first successful implementation of intraportal stent placement combined with right portal vein embolization as preoperative management against far advanced gallbladder carcinoma. The patient was a 66-year-old woman with obstructive jaundice, in whom computed tomography confirmed that gallbladder carcinoma had invaded the liver and that massive lymph node metastases involved the hepatoduodenal ligament. Portography also revealed severe stenosis of the main portal trunk to less than 2 mm in diameter. To prevent the contribution of intraportal thrombosis and ensure postoperative liver functional reserve, an intraportal metallic stent implantation was conducted simultaneously with right portal vein embolization via a single route using the percutaneous transhepatic approach. There were no complications following this technique, and the patient subsequently underwent hepato-ligament-pancreatoduodenectomy. The resected specimen disclosed a well-expanded stent containing no thrombus. This method could therefore be an amenable strategy for the preoperative treatment of far advanced biliary malignancies in selected patients.

Aged↗
PubMed1998

Attachment of nontypable Haemophilus influenzae to human pharyngeal epithelial cells mediated by a ganglioside receptor.

Nontypable Haemophilus influenzae (NTHI) is one of the major pathogens of human respiratory infections and has the ability to attach to pharyngeal epithelial cells. We characterized the epithelial cell receptor to which NTHI bind. Neuraminidase pretreatment of pharyngeal epithelial cells resulted in a significant decrease in NTHI attachment, suggesting sialic acid as an important component of the receptor. The attachment was not decreased in NTHI pretreated with 1,000 microg/ml of fucose, N-acetyl-neuraminic acid, N-acetyl-glucosamine, N-acetyl-galactosamine, acetyl-salicylic acid and colominic acid. Only treatment with gangliosides D1a, D1b and D2 at a concentration of 12.5 microg/ml significantly decreased the attachment. On the other hand, treatment with gangliosides M1, M2, M3, D3, T1b and asialoganglioside M1 did not decrease the attachment of NTHI. Only ganglioside D2 inhibited the attachment significantly at a concentration of 12.5 ng/ml. Other isolates of NTHI showed a decrease in attachment after treatment with ganglioside D2. Treatment of cells with anti-human GD2 monoclonal antibody also decreased the attachment of NTHI in a dose-dependent manner. This study indicates that sialic acid glycoconjugate, GD2, is one of the receptors of NTHI on human pharyngeal epithelial cells.

Antibodies, Monoclonal↗
PubMed1998

Pharmacotherapy for personality disorders.

Double-blind, placebo-controlled trials of pharmacotherapy for personality disorders (PD) were reviewed, and the indications concluded were as follows: (1) Severe cases of both Borderline Personality Disorder (BDP) and Schizotypal Personality Disorder (SPD) respond to low dose antipsychotic drugs resulting in improvement of a broad spectrum of symptoms. They also respond to monoamine oxidase inhibitor (MAOI). Amitriptyline causes a paradoxical effect. (2) Borderline personality disorder with behavioral dyscontrol responds to carbamazepine which reduces actual episodes of dyscontrol, to an antipsychotic drug and to MAOI. Alprazolam is associated with an increase in suicidality and dyscontrol. Borderline personal disorder or Histrionic Personality Disorder with a tendency to suicide, responds to a depot antipsychotic drug. Personality disorders with aggressive behavior respond to lithium. Moderately severe PD with explosive behavior respond to oxazepam, but at a dose where the side effect is sedation. (3) Borderline personality disorder and SPD with psychotic symptoms respond to an antipsychotic drug which improves psychotic symptoms as well as neurotic symptoms. Emotionally Unstable Character Disorder with a disturbance of mood swings, responds to lithium. Adolescent PD respond to an antipsychotic drug. (4) Comorbid atypical depression of histrionic personality and BPD respond to MAOI or imipramine. Comorbid neurotic disorder of PD responds to dothiepin. Comorbid social phobia of avoidant and dependent PD responds to MAOI.

Antipsychotic Agents↗
PubMed1998

LDH to AST ratio in biliary pancreatitis--a possible indicator of pancreatic necrosis: preliminary results.

OBJECTIVE: Lactate dehydrogenase (LDH) has been reported to be a sensitive indicator of pancreatic necrosis (PN). In patients with biliary pancreatitis (BP), however, liver enzymes are generally elevated early in the course of the disease because of acute inflammatory liver cell injury caused by ampullary stones impacted during their transpapillary passage. Accordingly, the identification of PN using the initial high LDH activity as an indicator of PN in BP may not be accurate. In patients with ongoing PN, LDH would be expected to increase thereafter. We hypothesized that an elevation of the ratio of LDH to aspartate aminotransferase (AST) (LDH/AST) would better reflect PN in BP. METHODS: The plasma concentrations of the LDH/AST ratio over a 3-wk postadmission period were evaluated and compared with serial computed tomograpy (CT) scans of the abdomen in two groups of patients with BP, consisting of 5 PN patients and 17 non-PN patients. A group of 50 healthy adults served as controls for the LDH/AST ratio measurement. RESULTS: On postadmission days 1 and 2, the LDH/AST ratios in both groups of patients were low, with no significant difference. In the PN patients, the LDH/AST ratio increased thereafter, reached peak values, and decreased. In the non-PN patients, the LDH/AST ratio increased gradually, but remained within the control range. In the PN patients, the LDH/AST ratios on postadmission days 3, 5, and 7 were significantly higher than those of the non-PN patients. The CT scans of the abdomen of the PN patients showed an initial edematous pancreas with the development of late PN. The peak values of the LDH/AST ratio correlated well with the extent of PN. CONCLUSION: An elevated LDH/AST ratio identifies patients who develop PN. The LDH/AST ratio could be used as an indicator of PN in BP patients.

Adult↗
PubMed1998

Comparison of valproate and phenobarbital treatment after status epilepticus in rats.

OBJECTIVE: To investigate the long-term effects of two widely used antiepileptic medications, valproate and phenobarbital, on learning and behavior in the kainic acid (KA) model of epilepsy. BACKGROUND: Prior clinical and animal studies have demonstrated that phenobarbital administered during development may result in subsequent cognitive impairment. It is unclear whether these adverse effects of phenobarbital extend to other antiepileptic drugs. METHODS: A convulsant dose of KA was administered to rats on postnatal day (P) 35. From P36-75 rats received daily injections of phenobarbital (PH), valproate (VPA), or saline and spontaneous seizure frequency was monitored with video recordings. After tapering of the drugs, the rats were tested in the water maze (a measure of visuospatial memory) and handling test (a measure of emotionality). Brains were then analyzed for histologic lesions. RESULTS: KA caused status epilepticus in all the rats. In the PH- and saline-treated groups, there was impaired learning in the water maze, increased emotionality, recurrent seizures, and histologic lesions in the hippocampal areas CA3, CA1, and dentate hilus. However, VPA-treated rats had no spontaneous seizures, abnormalities in handling, or deficits in visuospatial learning, and had fewer histologic lesions than animals receiving KA alone. CONCLUSIONS: The long-term consequences of AED treatment during development are related to the drug used. VPA treatment after KA-induced status epilepticus prevents many of the neurologic sequelae typically seen after KA.

Animals↗
PubMed1998

[SMANCS-TAE combined with PEI in the treatment for hepatocellular carcinoma].

From January 1996 to August 1997, 24 patients with advanced hepatocellular carcinoma (HCC) equal to or more than 2 cm (mean +/- SD; 4.1 +/- 3.0 cm) in main tumor diameter were treated by SMANCS-TAE (20 cases) or SMANCS-TAI (4 cases) combined with PEI. Six cases had solitary lesion, 16 cases had multiple lesions, and 2 cases had massive lesions. After this combination therapy, 21 of 24 cases had complete tumor necrosis. During 3 to 19 months follow up period, 12 cases had cancer-free survival (SMANCS-TAI; 3 cases), and 9 cases had tumor recurrences (3 cases were local recurrences and 6 cases involved new lesions). Two cases died of hepatic infarction and cancer death, however, the remaining 22 cases were surviving. SMANCS-TAE combined with PEI is useful treatment for advanced large or multiple HCC lesions in patients who are poor surgical risks.

Aged↗
PubMed1998

[Immunohistochemical study of p53, p27 and PCNA expression in esophageal cancer].

We evaluated the clinical significance of p53, p27 and PCNA expressions in esophageal squamous cell carcinomas. Operative specimens obtained from 70 patients with esophageal squamous cell carcinomas were investigated by staining with antibodies against p53, p27 and PCNA. The correlations among p53, p27 and PCNA expression, clinicopathologic factors and prognosis were studied. The expression of p53 was observed in 55.7%, and it did not correlate to histologic classification, growth pattern, and lymphatic invasion. The expression of p27 was observed in 48.6%, and it correlated to lymph node metastasis. The PCNA positive index (PCNA-PI) was high in the p27 negative cases. The p53 positive and p27 negative group revealed the worst survival rate among groups. Therefore, the p27 positive case, often associated with well differentiated carcinoma, tends to have a slower tumor-growth rate and better prognosis. It is suggested that immunohistochemical assessment on the p53 and p27 expressions would be useful to the recognize the malignant potential and differentiation of squamous cell carcinoma of the esophagus.

Aged↗
PubMed1997

Seizure-induced glutamate release in mature and immature animals: an in vivo microdialysis study.

A glutamate biosensor was used to measure extracellular glutamate concentrations in the hippocampus of mature and immature animals. Significant elevations of extracellular glutamate were observed following seizures induced by either kainic acid or pilocarpine. The degree of glutamate increase following seizures was similar in both mature and immature animals. These results suggest that excitotoxicity may play a role in seizure-induced brain damage in the adult brain. In the immature brain, however, no brain damage is seen after seizures, suggesting that glutamate release may not cause as significant excitotoxic damage early in development.

Aging↗