Contribution of passive transport mechanisms to the intestinal absorption of beta-lactam antibiotics

The transport characteristics of aminopenicillins (ampicillin and amoxicillin), aminocephalosporins (cephalexin, cephradine and cefadroxil) and cefazolin have been compared with those of an actively transported substance (D-glucose) and a passively transported substance (L-glucose). Although the initial uptake of the aminocephalosporins was stimulated in the presence of an inward H+ gradient, there was no overshoot in the uptake of any of the drugs tested, even in the presence of an H+ gradient. Also, the time course and the degree of uptake of these drugs were similar to those of L-glucose, especially in the absence of an H+ gradient. These results suggest that the beta-lactam antibiotics tested, like L-glucose, pass through the rat intestinal brush border membrane mainly by passive diffusion. However, the differences in absorption between these drugs, like the differences in their disappearance from a proximal loop of rat intestine, cannot be explained by a simple permeation process alone.     

Gastric leiomyoblastoma: report of a case

The case of a 38-year-old man with an exogastric leiomyoblastoma is reported. CT and ultrasound examinations revealed a large mass in the left hypochondrium that had both solid and cystic components. These findings mimicked those of cystadenoma of the pancreas. Because of intraperitoneal hemorrhage in the preoperative course, emergency laparotomy was performed. A large tumor was found to arise from the greater curvature of the stomach. The diagnosis was confirmed histologically.     

Duodenum-Preserving Resection of the Head of the Pancreas: The Significance as a Diagnostic Therapy for the Lesion in the Pancreatic Head

A 75-year-old man who was diagnosed as having mucin-producing pancreatic cystic lesion ofthe main pancreatic duct by duodenoscopic examination was reported. Because of the low malignant potential of such lesions, duodenum-preserving resection of the head of the pancreas was performed, and the intra-operative histological examination showed no malig-nancy of the resected pancreatic head and no other surgical procedures, such as lymph-adenectomy nor pancreato-duodenectomy were necessary. The significance of this case report lies in that a less invasive operation should be selected at first to diagnose whether the lesion is malignant or not, and als0 that the selected operation itself must be sufficient to resect an adequate part of the pancreatic tissue involving the cystic lesion, ifnot malignant. Here, we report the process to select the procedure and the surgical technique.     

Hemodynamic and volume changes by recombinant human erythropoietin (rHuEPO) in the treatment of anemic hemodialysis patients

Hemodynamic and volume changes induced by recombinant human erythropoietin (rHuEPO) treatment were investigated in 12 chronic hemodialysis patients with refractory anemia. After rHuEPO administration for 49 to 151 days, hematocrit (Ht) significantly improved from 19.4 +/- 2.3 to 30.1 +/- 1.1% (Mean +/- SD). Mean blood pressure (MBP) increased slightly but significantly from 78.8 +/- 13.2 to 88.9 +/- 16.9 mmHg. Hemodynamically, total peripheral resistance index (TPRI) increased significantly from 1,444 +/- 367 to 2,146 +/- 470 dynes.sec.cm-5.m2, while cardiac index (CI) decreased significantly from 4.49 +/- 0.85 to 3.37 +/- 0.60 l/min/m2. Both pulse rate (PR) and stroke volume index (SVI) also decreased significantly, but blood volume (BV) remained unchanged. Plasma renin activity and plasma norepinephrine decreased significantly. There were positive correlations between the change of MBP and that of CI, and between the change in CI and that of BV, respectively (p less than 0.05 or less). In conclusion the improvement of anemia using rHuEPO is hemodynamically associated with an increase in TPRI and a decrease in CI as well. Blood pressure elevation seems to be caused by an inappropriately minor reduction of CI. The contribution of humoral factors is not suggested.     

Cerebral type of Lewy body disease

A cerebral type of Lewy body disease (LBD) is proposed. Lewy body disease was split formerly into three types: brainstem type, transitional type and diffuse type. The diffuse type is now called diffuse Lewy body disease (DLBD). These three types are characterized pathologically by the presence of a large number of Lewy bodies in the CNS. In the brainstem type, Lewy bodies are numerous in the brainstem and diencephalon nuclei, and in DLBD, a vast number are present not only in these nuclei but also in the cerebral cortex and amygdala. In the cerebral type of LBD, as many Lewy bodies are found in the cerebral cortex and in the amygdala as there are in DLBD, but only rarely are they present in the brainstem and diencephalon nuclei. Thus, this type of LBD is different from other types in that it has no parkinson pathology. Therefore, parkinsonism fails to occur throughout the whole clinical course of this disease. The existence of a cerebral type of LBD suggests that Lewy bodies occur in the cerebral cortex earlier than in the brainstem nuclei and that cortical Lewy bodies appear even when the mesocortical dopaminergic system is intact. In addition, this might explain why dementia frequently precedes parkinsonism in DLBD.     

Induction and activation of the aryl hydrocarbon receptor by IL-4 in B cells

It is widely known that IL-4 and IL-13 act on various kinds of cells, including B cells, resulting in enhancement of proliferation, class switching to IgE and expression of several surface proteins. These functions are important for the recognition of the various antigens in B cells and are known to be involved in the pathogenesis of allergic diseases. However, it has not been known whether IL-4/IL-13 is involved in the metabolism of various kinds of xenobiotics including 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), and it remains undetermined whether TCDD, an environmental pollutant, influences IgE production in B cells, exaggerating allergic reactions. We identified IL-4- or IL-13-inducible genes in a human Burkitt lymphoma cell line, DND-39, using microarray technology, in which the AHR gene was included. The AHR gene product, the aryl hydrocarbon receptor (AhR), was induced by IL-4 in both mouse and human B cells in a STAT6-dependent manner. IL-4 alone had the ability to translocate the induced AhR to the nuclei. TCDD, a ligand for AhR, rapidly degraded the induced AhR by the proteasomal pathway, although IL-4-activated AhR sustained its expression. AhR activated by IL-4 caused expression of a xenobiotic-metabolizing gene, CYP1A1, and TCDD synergistically acted on the induction of this gene by IL-4. However, the induction of AhR had no effect on IgE synthesis or CD23 expression. These results indicate that the metabolism of xenobiotics would be a novel biological function of IL-4 and IL-13 in B cells, whereas TCDD is not involved in IgE synthesis in B cells.     

No difference in serum leptin concentrations between urban-dwelling Austronesians and Non-Austronesians in Papua New Guinea.

Pacific Islands populations can be broadly divided into Austronesians (AN) and Non-Austronesians (NAN); obesity and type 2 diabetes are prevalent in the former, although leptin levels in both groups have seldom been investigated. Thirty-seven (20 male and 17 female) adult pairs, matched by age and percent body fat, from AN-speaking Balopa and NAN-speaking Huli, all of whom migrated to settle in Port Moresby, the capital of Papua New Guinea, were selected for comparison of their serum leptin concentrations. The Balopa did not differ significantly from the Huli in age (30.5 +/- 9.7 and 30.0 +/- 8.7 years for males, 33.7 +/- 8.9 and 34.1 +/- 7.5 years for females, respectively) or percent body fat (19.4 +/- 5.6 and 18.8 +/- 4.6 for males, 34.1 +/- 6.2 and 33.3 +/- 5.0 for females), although the BMI of females was lower in the Balopa (26.4 +/- 4.9) than in the Huli (29.7 +/- 4.7) (P = 0.02). In both ethnic groups, females had markedly higher leptin concentrations than males, but there was no significant inter-group difference in males (3.5 +/- 2.6 and 3.1 +/- 4.7 ng/ml, P = 0.14) or females (22.7 +/- 12.9 and 19.7 +/- 11.9 ng/ml, P = 0.40), after controlling for lifestyle factors and serum lipids. Multiple regression analysis revealed that significant predictors of leptin concentration were % body fat (beta = 0.58), sex (male, 0; female, 1; beta = 0.27), and smoker status (non-smoker, 0; smoker, 1; beta = -0.15) (R(2) = 0.80), implying that the leptin concentration was primarily determined by lifestyle-derived body fatness. In conclusion, the NAN populations do not endogenously differ in leptin status from the AN populations, who have been recognized as a typical group with a "thrifty" genotype.     

Immunohistochemical study of synphilin-1 in brains of patients with dementia with Lewy bodies - synphilin-1 is non-specifically implicated in the formation of different neuronal cytoskeletal inclusions

The caudal part of the fastigial nucleus, or the fastigial oculomotor region (FOR), plays an important role in executing accurate saccades. Inactivation of a monkey FOR leads to dysmetric saccades. Currently available data suggest that the dysmetria could be described as a parametric, uniform change in saccadic gain or, alternatively, as a constant error in the specification of the saccadic goal. To discriminate between these two possibilities, we examined the effect of FOR inactivation in the monkey. After a unilateral injection of muscimol into the FOR, ipsiversive saccades overshot a target. Gains were similar for movements of different sizes. The overshoot increased proportionately with the target distance and had a very small constant component. The present study indicates that the hypermetria of ipsiversive saccades after inactivation of the monkey FOR is primarily due to a uniform gain increase for all sizes of saccades.