Parthenogenetic development of bovine oocytes treated with ethanol and cytochalasin B after in vitro maturation

The present study was conducted to investigate the effects of different culture durations (24-36 hr) on bovine oocyte maturation in vitro and the effect of the presence or absence of cumulus cells at the time of treatment to induce parthenogenetic activation (exposure to ethanol and cytochalasin B; CB) (experiment I). The effects of dosage (2.5 or 5.0 micrograms/ml) and incubation time (2.5, 5, or 10 hr) in CB (experiment II) on the subsequent development to the blastocyst stage in vitro was also investigated. In experiment I, cleavage and development to the blastocyst stage were not affected by the presence or absence of cumulus cells at the time of parthenogenetic activation. However, the 24-hr culture duration for in vitro maturation had a significantly lower rate of development to the blastocyst stage than the longer culture durations (27-36 hr). In experiment II, treatment with 5 micrograms/ml CB for 5 hr showed the highest percentage of development to blastocyst in the oocytes matured for both 27 and 30 hr. To determine the viability of the parthenogenetic embryos (morulae and blastocysts), four recipient heifers received two embryos each, and one heifer was found to be pregnant on day 35 following transfer. Although fetal heartbeat was not observed, the subsequent estrus was prolonged in all heifers. The present results demonstrate development of in vitro-matured, parthenogenetically activated bovine embryos up to the preimplantation stage.

Regionalized expression of the Dbx family homeobox genes in the embryonic CNS of the mouse

Here we report the identification of a novel homeobox gene family Dbx in mouse, which consists of Dbx and Dbx2. The two genes share similar structural organization and are encoded by different chromosomes. The predicted Dbx and Dbx2 proteins share 85% identity in their homeodomain amino acid sequences, but otherwise showed no significant similarity. Characterization of the expression of these two genes in the embryos suggested their role in the development of the CNS. In the forebrain, Dbx is expressed in various regions, while Dbx2 showed a more restricted pattern of expression. In the midbrain, the expression domains of Dbx and Dbx2 overlap along the dorso-lateral wall of the ventricle. In the hindbrain and spinal cord, both genes are expressed in the boundary separating the basal and alar plates, which seems to correspond to the sulcus limitans. Expression of the Dbx/Dbx2 genes is restricted to the ventricular region of the embryonic CNS except for that of Dbx in the septum of the telencephalon. Together these observations indicate possible participation of the members of the Dbx family in regionalization of the CNS. While the expression of Dbx was restricted to the CNS, Dbx2 was also expressed in some of the mesenchymal cells, such as limb buds and tooth germs.

Expression of the Vax family homeobox genes suggests multiple roles in eye development

BACKGROUND

Homeobox gene products are thought to regulate target genes involved in the regional specification of tissues and organs. Several genes play roles in eye development.

RESULTS

We isolated two new mouse homeobox genes, Vax1 and Vax2, expressed in retina primordium. The two genes share the same gene organization, consisting of three exons with predicted amino acid sequences identical in the homeodomain but diversified in other regions. At 9. 5 days post coitum, both Vax genes were expressed in optic vesicles. At 11.5-14.5 dpc, Vax1 became restricted to the optic stalk, while Vax2 was expressed in the ventral half of the neural retina. Mapping of Vax2 between D6Mit3 and D6Mit8 on chromosome 6 indicated a possible linkage with Emx1.

CONCLUSIONS

The expression patterns of Vax genes suggest separate and specific involvement in eye development. Vax1 may contribute to differentiation of the neuroretina, pigmented epithelium and optic stalk, while Vax2 could function in the establishment of the dorso-ventral axis of the retina and the visual system. The chromosomal location of Vax2 suggests that Vax2-Emx1 and Vax1-Emx2 arose by chromosome duplication of the same ancestral gene.

Thickness of fibrous capsule after implantation of hydroxyapatite in subcutaneous tissue in rats

The present study evaluates in rats the histomorphometrical thickness of fibrous capsules that surround hydroxyapatite (HA) disks after implantation. HA disks were implanted into the subcutaneous tissue of 79 rats for 1 day to 20 months. Decalcified histological sections stained with hematoxylin and eosin were examined. Fibrous capsule thickness (FCT) was measured using an objective micrometer. On the fourteenth day, primary fibrous capsules formed around implants. From that time point FCT increased with time of implantation. Within a given sample, FCT differed from one portion of the fibrous capsule to another, depending on which site faced the disks. FCT was thickest at the upper and lower portions of the disks, thinner at the lateral portions, and thinnest at the upper and lower ring-shaped portions. Two possible explanations for the above findings are discussed in this paper: (1) The area of contact between disk and tissue differs. (2) Chemical stimulation of implanted material caused by demineralization and remineralization may result from the varying thicknesses of fibrous capsules. FCT from upper and lower portions of HA disks increased by over 200% in the first 10 months and steadily increased about 20% over the next 10 months. Many studies have concluded that HA is useful for reconstructive surgery, so the long-term effects of FCT need further study.

The enhancement of cellular infiltration and vascularisation of a collagenous dermal implant in the rat by platelet-derived growth factor BB

The implantation of collagen-based dermal substitutes offers one means of management of full-thickness skin lesions. We have examined the effect of the recombinant BB homodimer of platelet-derived growth factor (rPDGF-BB) on the extent of cellular infiltration and vascularisation of collagen sponges implanted into full-thickness excision wounds in rats. Histological examination of sponges excised 14 and 21 days post-implantation in dose-response studies in which 0-4 micrograms rPDGF-BB were applied to the undersurface of each sponge, immediately prior to its implantation, demonstrated a progressively increased infiltration of host cells, especially fibroblasts, and enhanced capillary formation. With 4 micrograms rPDGF-BB, an enhanced infiltration of fibroblasts into sponges was already apparent 3 days post-implantation, and enhanced capillary formation was noticeable after 7 days. This neovascularisation was noted to be associated with improved survival of autologous split-thickness skin grafts applied to the sponges immediately following their implantation.

Histological reaction to hydroxyapatite in the middle ear of rats

OBJECTIVE

Present study was performed to evaluate the histological response of rat middle ear mucosa following implantation of Apaceram granules, a synthetic dense hydroxyapatite [Ca10(PO4)6(OH)2], prepared from commercially available synthetic auditory ossicle, and to assess the precise histological response of the rat middle ear to implantation of Apaceram granules, by microscopic examination of mucosal tissue at various time points after implantation.

METHODS

Apaceram granules were implanted in the temporal bulla of 32 rats. As control, sham surgery was performed in a group of ten rats. Bulla specimens were removed at 1, 3, 7, 14, and 30 days after surgery in the implant and control groups, and at 90, 180 and 300 days in the implant group. Specimens were decalcified, sectioned at a thickness of 6 microm, and stained with haematoxylin and eosin, and Mallory's azan for histological examination of mucosal tissue.

RESULTS

Evidence of inflammatory reaction was slightly greater in the implant group than in controls. Lymphocyte and macrophage counts were higher in the implant group 1 day after surgery, but decreased to similar levels by day 3, and continued to decrease thereafter, and few were observed in the implant group at 300 days. Neutrophils observed at 1 day after surgery were not evident in either group at 3 days. Gradual fibrosis development continued in both groups over all time points studied. Foreign body giant cells were never observed in either group. No bony reaction was observed in any specimen.

CONCLUSION

The results of this study suggest that Apaceram is biocompatible and suitable for reconstructive ear surgery.

Chronic Prototheca meningitis

A case of chronic meningitis caused by the achloric alga Prototheca wickerhamii is described, which has persisted for more than 6 years despite treatment with various antifungal agents. For the last year no treatment has been given, but the patient has no complaints.

Instructive role of a peripheral pattern for the central patterning of the trigeminal projection at the brainstem and thalamus revealed by an artificially altered whisker pattern

The central patterning mechanism of neuronal circuits is an important issue in developmental neuroscience. We report here the role of a peripheral whisker pattern for the patterning of the trigeminal projection at the brainstem and thalamus in the mouse somatosensory system. The whisker pattern was manipulated by infecting the embryonic epidermis with adenovirus harboring Shh. The ectopic expression of Shh led to the induction of extra whiskers and displacement of whiskers, where these whiskers were histologically normal. The altered whisker pattern was isomorphically represented in the brainstem (barrelette: subnuclei principalis and subnuclei interpolaris), thalamus (barreloid) and cortex (barrel) as revealed by cytochrome oxidase staining. The barrelette-like pattern of the parvalbumin became discernible by immunostaining at P7 in subnuclei principalis and at P4 in subnuclei interpolaris in normal mice. These are the barrelette neurons projecting to the thalamus and the local circuit within the barrelette. The barrelette-like parvalbumin pattern also exhibits the altered whisker pattern induced by the adenovirus harboring Shh. These results highlight the role the peripheral whisker pattern for the central patterning of the brainstem, thalamus, and cortex in the mouse somatosensory system.

Characteristics of neo red cells, their function and safety: in vivo studies

A new type of artificial oxygen carriers, the Neo Red Cells (NRCs) have been developed and investigated for oxygen transporting efficiency and safety in experimental animals. Stroma free hemoglobin from outdated human red blood cells together with inositol hexaphosphate as an allosteric effector under sterile, pyrogen free condition were encapsulated in liposomes and then were coated with polyethylene glycol bond to hydrogenated soy phosphatidylethanolamine as a surface modifier to prevent aggregation of NRCs in plasma. The efficiency of the NRCs in tissue oxygenation was studied in rabbits which were made severely anemic by drawing 85% of their blood and immediately replacing it with NRC solution. The animals, all recovered to pre-anemic conditions within 6-8 hr and lived normally until being sacrificed, 6 months after the exchange transfusion. The circulation half-life and tissue distribution of NRCs were studied using radiolabeled NRCs. Within the circulation, the half-life of NRCs was 21 hr and extravascularly, they were distributed mainly in and metabolized by the reticuloendothelial system within 7 days. Our observations suggest that the NRCs prepared and investigated in this study are efficient oxygen carriers without causing serious adverse reactions and can be prepared free from pathogenic micro-organisms by special filtration technique before encapsulation of Hb. Currently, experiments are ongoing to control auto-oxidation of oxyHb to metHb which is higher in NRCs than in native red cells at physiological conditions.

Long-term observation of subcutaneous tissue reaction to synthetic auditory ossicle (Apaceram) in rats

The present study evaluates histological characteristics of the soft tissue response to long-term implantation of Apaceram discs composed of dense hydroxyapatite in rats. Discs were implanted into the subcutaneous tissue of 76 rats for six to 20 months. Decalcified histological sections stained with haematoxylin and eosin (H & E) and Mallory's azan were examined. Different cell types surrounding implants were counted. The greatest proportion of macrophages was found at six months (13.5 per cent). This proportion gradually decreased to four per cent at 20 months. Small numbers of lymphocytes and foreign body giant cells were observed in every group, but neither neutrophils nor osteogenesis were observed in any specimens. Results of the present study and previous related studies indicate that despite reappearance of a small number of macrophages six months after implantation, Apaceram is useful for reconstructive surgery.

Subcutaneous tissue reaction to synthetic auditory ossicle (Apaceram) in rats

A study was carried out in order to obtain further information about the soft tissue response to thin Apaceram discs of dense hydroxyapatite (HA) implanted in rats for various periods of time between one day and 10 months. The Apaceram discs were implanted subcutaneously into the interscapular region of 33 rats. A sham operation was performed on eight rats used as controls. Decalcified histological sections stained with haematoxylin and eosin and Mallory's azan were examined and the different cell types found around the implants were counted. It was found that an acute inflammatory reaction occurred after one day and disappeared at about two weeks after implantation. In the test groups, macrophages and lymphocytes disappeared about one week later, and no inflammatory reaction was observed from one to three months. However, a tissue reaction occurred at six months with the appearance of macrophages and lymphocytes, and decreased gradually at 10 months. Meanwhile, a few foreign body giant cells at the Apaceram-tissue interface and a thick layer of fibrous connective tissue around the Apaceram disc were observed at 10 months. No osteogenesis was observed in any specimen. The results obtained so far suggest that Apaceram is still a useful material for reconstructive surgery, despite the possible appearance of a slight macrophage reaction at six months.

Mechanism of bone destruction due to middle ear cholesteatoma as revealed by laser-Raman spectrometry

In an investigation of the mechanism of bone destruction caused by chronic otitis media complicated with cholesteatoma, both the processes of demineralization and remineralization were studied in an animal model and clinically at the molecular level, using a laser-Raman spectrometer. From this investigation, it is proposed that the mechanism of bone destruction associated with cholesteatoma is a form of demineralization.

Evaluation of tinnitus patients by peroral multi-drug treatment

To evaluate patients complaining of subjective tinnitus, this study examined their response to peroral betahistine mesilate, vitamin B complex and diazepam in combination. Because three drugs were used together, it remains to be seen whether a single drug or a combination of drugs was effective. We issued questionnaires to 67 patients with tinnitus associated with sensorineural hearing loss of unknown etiology or tinnitus, despite normal hearing in pure tone audiometry and lack of distinct systemic disorders. Our original questionnaire contained seven items and allotted points for each item to facilitate evaluation. After prescribing the above drugs and observing patients' progress for 5 weeks, 50 of the 67 subjects were evaluated again by the same questionnaire. The present study evaluates tinnitus of patients as an example of clinical applications; this was not a controlled double blind study. It was found that, after patients took the prescribed medication, the total number of points were significantly reduced (paired t-test, P < 0.001). After medication, cases of bilateral tinnitus were significantly reduced from 27 to 14, and cases of two types of tinnitus sound, were significantly decreased from 22 to 11 (chi 2-test, P < 0.05). After 5 weeks of administration, 54% of patients felt treatment had been effective. Preliminary results suggest this peroral multi-drug treatment may provide relief for some patients with subjective tinnitus. However, long-term efficacy of the treatment was not investigated.

Subcutaneous inflammatory reaction to a synthetic auditory ossicle (Bioceram) in rats

Cellular response and inflammatory reaction to synthetic auditory ossicle (Bioceram) made from aluminium oxide are investigated. Local inflammatory effects are important in wound healing and in determining biocompatibility of an implant, necessitating the study of biologic effects of implants, especially inflammation and fibrous capsule formation. Bioceram discs were implanted subcutaneously in the interscapular region of rats for various periods of time, ranging from 1 day to 300 days. Histological sections 6 microns thick were stained with haematoxylin and eosin. Cell types around the implants were examined quantitatively by light microscopy. Inflammatory cell reaction to Bioceram decreased rapidly within 14 days, similar to the reaction in control groups. From 30 days to 300 days after implantation, there was continuous reduction to very low levels for macrophages and lymphocytes, but fibrous connective tissue capsule around implants matured. Preliminary results suggest that Bioceram is a satisfactory biocompatible material for reconstructive surgery from the viewpoint of cellular response. We also briefly discuss the different tissue responses in light of our previous study on hydroxyapatite (Apaceram).

Malignant fibrous histiocytoma of the maxillary sinus

A case of malignant fibrous histiocytoma arising primarily in the left maxillary sinus is described. The patient, a 39-year-old male, who had suffered from sinusitis for 20 years, began to have paresthesia or sharp pain of the left side of the face and toothaches of the left maxilla. At operation a white fibrous tumor developing extensively from the lateral wall to the upper and medial walls of the left maxillary sinus and into the ethmoidal sinus was noted. Following a gradual progression of dyspnea, he died approximately one year after the onset in spite of radiation therapy and anticancer chemotherapy. An autopsy revealed recurrence of the tumor in the left maxillary sinus with wide-spread metastases to the lungs, pleurae, pancreas, kidneys and bone marrows. The direct cause of death was respiratory failure due to extensive growths of the pulmonary and pleural metastases.

IgD multiple myeloma with renal involvement: case report

IgD multiple myeloma is a unique type of multiple myeloma which is characterized by increased serum IgD and IgD type M-component in immunoelectrophoresis. It frequently shows renal involvement but it is a rare form of myeloma. The distinctive features of IgD myeloma are the dominance in males, high frequency in younger persons, and the uncertain appearance of M-component in serum electrophoresis. We experienced 3 cases of IgD multiple myeloma with renal failure which required hemodialysis before IgD myeloma was diagnosed. It is important to consider IgD myeloma when treating the patients with renal involvement of unknown origin.

Reproducibility of pitch-matching test for tinnitus. Using a heptatonic scale

We evaluated the reproducibility of measured values obtained using a heptachord pitch-matching test (PMT). Investigation of the measured values by considering the minimum unit width limits of the testing scale revealed that the coincidence ratios of the measured values of intra-daily variations, intra-weekly variations and eight values measured consecutively in one test were as high as 100%, 94.8% and 83.3%, respectively. We therefore concluded that the reproducibility of this method is satisfactory. The measured values obtained by both ordinary one-octave-interval and heptachord PMT are compared in this article.

The effect of tranexamic acid on cochlear blood flow in guinea pigs measured by laser Doppler flowmetry

OBJECTIVE

This study investigated the vasoactive effect of tranexamic acid on the cochlear blood flow in guinea pigs.

METHOD

3 ml solution (infusion speed, 0.5 ml/min) containing different concentrations of tranexamic acid was intravenously infused into 15 guinea pigs under general anesthesia. The guinea pigs were grouped according to four levels of dosage of the medicine (470 mg/kg, n=6; 220 mg/kg, n=3; 4 mg/kg, n=3; 1 mg/kg, n=3). Before administering medicine, saline solution was administered in similar volume and speed as a control. The cochleas were surgically exposed and laser Doppler flowmetry monitored cochlear blood flow volume (CBF). The left femoral artery was cannulated to permit a transducer to monitor systemic blood pressure (BP).

RESULTS

(1) Stimulatory effect of tranexamic acid on CBF was dose-dependent at concentrations of 1-470 mg/kg and, (2) the time course of changes in CBF was almost identical to that in BP following tranexamic acid administration.

CONCLUSION

Preliminary findings suggest that intravenous administration of tranexamic acid increases CBF due to vasomotorial mechanism effect on BP.

Behavior of Photosystems II and I Is Modulated Depending on N Partitioning to Rubisco in Mature Leaves Acclimated to Low N Levels and Senescent Leaves in Rice

In mature leaves acclimated to low N levels and in senescent leaves, photosystems II and I (PSII and PSI, respectively) show typical responses to excess light energy. As CO2 assimilation is not transiently suppressed in these situations, the behavior of PSII and PSI is likely caused by endogenous biochemical changes in photosynthesis. In this study, this subject was studied in rice (Oryza sativa L.). Analysis was performed on mature and senescent leaves of control and N-deficient plants. Total leaf-N, Rubisco and chlorophyll (Chl) levels and their ratios were determined as biochemical parameters of photosynthesis. Total leaf-N, Rubisco and Chl levels decreased in the mature leaves of N-deficient plants and senescent leaves. The percentage of Rubisco-N in the total leaf-N decreased in these leaves, whereas that of Chl-N tended to remain almost constant in mature leaves but increased in senescent leaves. Changes in PSII and PSI parameters were best accounted for by the Rubisco-N percentage, strongly suggesting that the behavior of PSII and PSI is modulated depending on changes in N partitioning to Rubisco in mature leaves acclimated to low N levels and in senescent leaves. It is likely that a decrease in N partitioning to Rubisco leads to a decrease in Rubisco capacity relative to other photosynthetic capacities that inevitably generate excess light energy and that the operation of PSII and PSI is modulated in such situations.

Fibrinolytic activity of middle ear fluid in otitis media with effusion

In order to investigate the prolonged factors of otitis media with effusion, hydrolytic activities for specific substrates of plasmin and plasminogen activator (P.G.-activator) and the activity for fibrin degradation (fibrinolysis) were measured. Materials were middle ear fluids of 36 cases diagnosed as unilateral otitis media with effusion. Age of the patients were from 28 to 88 years old (mean: 61.3). Using specific substrates, determinations of P.G.-activator activity and plasmin activity were made by the method of Claeson et al. and fibrinolysis was determined by the standard fibrin plate. The results are shown below: 1) Both activities for decomposition of amide against the specific substrates of plasmin and of P.G.-activator were revealed. 2) Concerning fibrinolysis in all cases, we divided them into 3 groups; fibrinolysis (-) group of 8 cases (22.2%) which could not dissolve fibrin at all, fibrinolysis (+) group of 17 cases (47.2%) which could dissolve fibrin. Fibrinolysis (+/-) group of 11 cases (30.6%) of which the presence of fibrin dissolution was unknown. 3) The progress of fibrinolysis was observed by serial collection of middle ear fluid in the same side ear of 5 cases out of 17 cases having much activity for fibrin degradation, and lowering of fibrinolytic activity was revealed in 4 out of these 5 cases as the result. On the basis of these results, we discussed on the process of prolongation in this disease from the standpoint of the presence of fibrinolytic activity in the middle ear fluid.

[A case of familial lecithin: cholesterol acyltransferase deficiency]

Lecithin: cholesterol acyltransferase (LCAT) is an enzyme that catalyzes the esterifying reaction of cholesterol in plasma high density lipoprotein (HDL). Deficiency of LCAT is a rare hereditary disease characterized by several clinical symptoms such as proteinuria, corneal opacity, and anemia due to a shortened life span of erythrocytes. In this communication, we report a case of 40 year-old female patient of LCAT deficiency. She visited a hospital for work-up of proteinuria, corneal opacity and anemia. Activity of her serum LCAT was found to be extremely low, and characteristic changes in plasma lipids due to deficiency of LCAT was observed: those were marked decreases in HDL-cholesterol, degree of esterification in serum cholesterol, and apoprotein A-I, A-II, B and C-II levels. The diagnosis of LCAT deficiency was finally made. We studied about histopathological changes in the patient's kidney, and erythrocyte membrane lipid composition and fluidity. Histopathological findings in renal biopsy were follows: a) Light microscopy showed spherical deposits stained with periodic acid-Schiff in mesangial matrix and adjacent capillary loops, and hyaline deposits in arterioles, b) Electron microscopy showed vacuoles in mesangial matrix and along the glomerular basement membranes. In erythrocyte membrane lipids, increase of cholesterol to phospholipid molar ratio was evident, being accompanied by changes in phospholipid fractions: increase of phosphatidylcholine, and decreases of phosphatidylethanolamine, sphingomyelin and lysophosphatidylcholine. In phospholipid acyl chains, increase of C18:2 and decreased of C18:1 were evident in the patient. Erythrocyte membrane fluidity was found to be decreased in the patient in a measurement by pyrene, probably being related to the changes in membrane lipid composition.(ABSTRACT TRUNCATED AT 250 WORDS)

A proposal on the hard tissue remineralization in osteoarthritis of the knee joint investigated by FT-IR spectrometry

An investigation was performed on hard tissues of the affected area in the cases of osteoarthritis of the knee joint by using Fourier transform infrared spectroscopy (FT-IR) to obtain the information on components and characteristics of the compounds in the hard tissues at the molecular level. Biological specimens used were: normal cortical bone, normal cancellous bone, sclerotic area of the affected site (subchondral bone), osteophyte and cartilage of the affected joint. FT-IR spectra of these specimens were measured and spectroscopic characteristics of various types of hard tissues were quantified. As the result of the analysis, signal ratio of PO4(3-) to amide I (PO4(3-)/amide I) was 0 in cartilage, and the ratio was at the highest in normal cortical bone of the ulna, being as high as 1.82. The signal ratio of the sclerotic area of the affected site was 1.69, and this was higher than the values in osteophyte (1.44) or cancellous bone of the tibia (1.61). It is inferred from these data that the degree of remineralization was considerably higher in osteoarthritis of the knee joint. On the other hand, in the osteophyte, which is frequently seen in the radiography of osteoarthritis, it was 1.44 for the attached osteophyte and 1.37 for the detached osteophyte, and these values were lower compared with the values in the sclerotic area of the affected site (1.69). From these results, it appears that remineralization of mineral components is very likely to occur under the acidic conditions in the articular region in this disease. We propose that the mechanism of hard tissue formation in the knee joint of osteoarthritis is a form of remineralization.