Biomedical subjects

Y Kanno

Publications and source records attributed to Y Kanno.

At least 37 records · Page 2Linked to original sources

PubMed2001

Crystal nephropathy: a variant form of myeloma kidney--a case report and review of the literature.

Cast nephropathy is the most common form of myeloma kidney, and also one of the major determinants of a patient's prognosis. We experienced a case of multiple myeloma with acute renal failure that was associated with massive crystal deposition in kidney and bone marrow. Large crystal formation in myeloma kidney is a rare pathological finding in renal biopsies. In the literature, most of the cases with multiple myeloma with extracellular crystal deposition often have a rapidly progressive course with a poor prognosis. Ball et al. [1993] suggested that this type of extracellular crystal deposition be designated as "crystalglobulinemia syndrome". The characteristics of the clinical and histopathological features, rapid progression and poor outcome, and crystal formation in the tubules found in the present case and in those previously reported, support the proposal of a new concept of "crystal nephropathy".

Aged↗

PubMed2001

Development of "Standards for the Evaluation of Hospital Infection Control Policies and Procedures, the Second Version".

The Japan Society for Quality in Health Care (JSQua) created "Standards for the Evaluation of Hospital Infection Control Policies and Procedures, the First Version" in 1998 and carried out third-party surveys. Through the experience of those surveys, we revised the standards and created a second version in 1999. The surveyors felt that in using the second version of the standards it would be easier to evaluate the quality of hospital care and that these standards would be more widely applied.

Cross Infection↗

PubMed2000

CD134L engagement enhances human B cell Ig production: CD154/CD40, CD70/CD27, and CD134/CD134L interactions coordinately regulate T cell-dependent B cell responses.

CD134 is a member of the TNFR family expressed on activated T cells, whose ligand, CD134L, is found preferentially on activated B cells. We have previously reported that the CD70/CD27 interaction may be more important in the induction of plasma cell differentiation after the expansion phase induced by the CD154/CD40 interaction has occurred. When CD134-transfected cells were added to PBMCs stimulated with pokeweed mitogen, IgG production was enhanced in a dose-dependent fashion. Addition of CD134-transfected cells to B cells stimulated with Staphylococcus aureus Cowan I strain/IL-2 resulted in little if any enhancement of B cell IgG production and proliferation. We found that while CD134-transfected cells induced no IgG production by themselves, it greatly enhanced IgG production in the presence of CD40 stimulation or T cell cytokines such as IL-4 and IL-10. The addition of CD134-transfected cells showed only a slight increase in the number of plasma cells compared with that in the culture without them, indicating that an increased Ig production rate per cell is responsible for the observed enhancing effect of CD134L engagement rather than increase in plasma cell generation. These results strongly suggest different and sequential roles of the TNF/TNFR family molecules in human T cell-dependent B cell responses through cell-cell contacts and the cytokine network.

Adjuvants, Immunologic↗

PubMed2000

cAMP-Dependent potentiation of the Ca(2+)-activated release of the anionic fluorescent dye, calcein, from rat parotid acinar cells.

A recent study indicates that elevation of [Ca(2+)](i) enhances the release of calcein, an anionic fluorescent dye, from isolated exocrine acinar cells, so cytoplasmic calcein is useful for monitoring the secretion of organic anions. In this study, we investigated the effect of cAMP on the calcein release evoked by elevation of [Ca(2+)](i). Isoproterenol, forskolin and dibutyryl cyclic AMP (dbcAMP) did not induce the release of calcein from isolated parotid acinar cells, but they potentiated the carbachol-induced release of calcein. Although cytoplasmic calcein is released through an increase in [Ca(2+)](i), isoproterenol potentiated the carbachol-induced release of calcein without affecting the increase in [Ca(2+)](i) evoked by a high concentration of carbachol (10(-6) M). Charybdotoxin, a K(+) channel blocker, inhibited both the carbachol-induced release and the potentiation by isoproterenol. However, the calcein permeation pathways mediating the carbachol-induced release and the isoproterenol-potentiated release exhibited distinct sensitivities to anion channel blockers. Our results indicate that the calcein release induced by carbachol is potentiated through an increase in intracellular levels of cAMP. Although both the Ca(2+)-activated release and the cAMP-potentiated release may be coupled to Ca(2+)-activated K(+) efflux, increases in both [Ca(2+)](i) and [cAMP](i) may activate the calcein conduction pathway which is not activated by an increase in [Ca(2+)](i) alone.

Adrenergic beta-Agonists↗

PubMed2000

Role of T lymphocytes in renal disease in HIV-transgenic mice.

The pathogenesis of human immunodeficiency virus (HIV)-associated focal segmental glomerulosclerosis (FSGS) has remained obscure. It has been proposed that renal parenchymal cells may be infected with HIV-1. If such infection occurs, the target cells would be expected to express viral proteins and thus could be targets for cytotoxic T lymphocytes. We previously described mice transgenic for a gag-pol-deleted HIV-1 genome that developed FSGS. In the present study, we tested the requirement for functional T cells in the evolution of renal disease in this model. We bred the HIV-transgenic mice (T26) with athymic nude mice to produce athymic T26 mice. We confirmed by flow cytometry of peripheral blood, thymus, lymph node, and spleen that the athymic T26 mice lacked mature T cells. The athymic T26 mice developed renal disease characterized by FSGS, tubular atrophy and dilatation, and interstitial infiltrate that was qualitatively identical to that seen in the parental T26 mice. Quantitative assessment of the athymic T26 mouse kidneys showed that glomerulosclerosis, tubular injury, and interstitial infiltrate were less severe compared with the parental T26 mouse kidneys. Although T26 mouse kidneys had a mixed cellular infiltrate composed of CD4 cells, CD8 cells, and macrophages, interstitial infiltrates within the athymic T26 mouse kidneys included macrophages but lacked both CD4 and CD8 cells. The renal expression of the HIV transgene was 1. 7-fold greater in T26 mice compared with athymic T26 mice. We conclude that mature T cells are not absolutely required for the development of HIV-associated nephropathy in transgenic mice but that, in their absence, renal disease is significantly milder. These data suggest that T-cell-mediated cytotoxicity directed against renal cells expressing virally encoded proteins is not an essential feature of renal pathogenesis in this model.

Animals↗

PubMed2000

Visualization of the secretory process involved in Ca2+-activated fluid secretion from rat submandibular glands using the fluorescent dye, calcein.

The central feature of fluid and electrolyte secretion by salivary acinar cells is transepithelial Cl- movement as a driving force for the secretion. However, little is known about the membrane localization and regulation by agonists of various anion channels. To characterize the anion transport and fluid secretion, we visualized the secretory process induced by the cholinergic agonist, carbachol (CCh), using the anionic fluorescent dye, calcein, under a confocal laser scanning microscope. The fluorescence of calcein loaded into the isolated acini was spread diffusely throughout the cytoplasm and was less intense in the secretory vesicles which occupied the apical pole. Cytoplasmic calcein was released into intercellular canaliculi just after the addition of CCh, depending upon a rise in [Ca2+]i by Ca2+ release from intracellular stores. Thereafter, the formation of watery vacuoles connected with intercellular canaliculi was visualized in the calcein-loaded acini, depending upon external Ca2+. Both the calcein release and vacuole formation were inhibited by suppressing the Ca(2+)-activated K+ efflux. The calcein release was also affected by the external anion substitution, suggesting that calcein is released through an anion channel. In the isolated, perfused glands, CCh-induced fluid secretion was sustained in two phases, whereas the loaded calcein was initially and transiently released into the saliva. By revealing the [Ca2+]i dependence and sensitivities to channel blockers, our results suggest that the initial phase of CCh-induced fluid secretion was evoked in association with the release of the organic anion, calcein, and the late phase of fluid secretion, during which calcein is less permeable, was associated with the formation of watery vacuoles. Thus, the anion channels possessing the distinct property of anion permeation may be activated in the initial phase and late phase. These results indicate that the anionic fluorescent dye, calcein, is useful for visualizing the process of Ca(2+)-dependent fluid secretion, and for clarifying the relation between fluid secretion and anion transport.

Animals↗

PubMed2000

Influence of the timing of initiating antihypertensive therapy in hypertensive rats with renal failure.

The important contribution of hypertension to the progression of renal failure is well realized. However, it have been less discussed which drugs are suitable for the different stages of progressive renal failure. The present study examined the effects of timing of antihypertensive therapy using calcium channel blocker and angiotensin converting enzyme inhibitor in 5/6 nephrectomized spontaneously hypertensive rats (SHRs). Forty male 6 week old SHRs were divided into 5 groups (n=8 in each group), and they were placed on a high salt diet after 5/6 nephrectomy. Group 1, high salt diet without any drug. Group 2 received 0.2 mg/kg/day of amlodipine and group 3 received 0.2 mg/kg/day of enalapril mixed in the high salt diet from week 6 respectively. Similarly group 4 received the same doses of amlodipine, and group 5 received the same doses of enalapril from week 10. Each drug protected from increasing blood pressure in 4 groups, and no significant difference was observed between the effects of amlodipine and enalapril. Proteinuria was reduced with both drugs. In histopathological evaluation, glomerulosclerosis was controlled only in group 2, and arterio/olosclerosis was significantly suppressed in all treated groups except group 5. From these results, both amlodipine and enalapril are renal protective in early stage of renal failure with hypertension. However, in advanced stage of renal failure, amlodipine is superior in its renal protective effect.

Amlodipine↗

PubMed2000

Identification of hepatic tamoxifen-DNA adducts in mice: alpha-(N(2)-deoxyguanosinyl)tamoxifen and alpha-(N(2)-deoxyguanosinyl)tamoxifen N-oxide.

Tamoxifen-DNA adducts detected in the liver of mice treated with tamoxifen have not yet been identified. In the present study a new type of tamoxifen-DNA adduct, four stereoisomers of alpha-(N:(2)-deoxyguanosinyl)tamoxifen N:-oxide 3'-monophosphate (dG(3'P)-N:(2)-TAM N:-oxide) were prepared as standard DNA adducts by reacting 2'-deoxyguanosine 3'-monophosphate with trans-alpha-acetoxytamoxifen N:-oxide in addition to four stereoisomers of alpha-(N:(2)-deoxyguano- sinyl)tamoxifen 3'-monophosphate (dG(3'P)-N:(2)-TAM) that was reported previously. Liquid chromatography-electrospray ionization-mass spectrometry of the reaction products gave the most abundant ion at m/z 731 ([M - H](-)), which corresponded to dG(3'P)-N:(2)-TAM N:-oxide. The modified products digested by alkaline phosphatase corresponded to the isomers of dG-N:(2)-TAM N:-oxide whose structures were identified previously by mass spectrometry and nuclear magnetic resonance. Using these standard markers, we analyzed the hepatic DNA adducts of female DBA/2 mice treated with tamoxifen at a dosage of 120 mg/kg/day for 7 days by (32)P-post-labeling coupled with an HPLC/radioactive detector. Mixtures of eight isomers of dG(3'P)-N:(2)-TAM and dG(3'P)-N:(2)-TAM N-oxide were separated into six peaks, since each of the cis epimers were not separated under the present HPLC conditions. Nine adducts were detected in all liver samples of mice. An epimer of trans-dG(3'P)-N:(2)-TAM was detected as the principal DNA adduct at a level of 29.0 adducts/10(8) nucleotides, which accounted for 53.3% of the total tamoxifen-DNA adducts. Lesser amounts of cis-dG(3'P)-N:(2)-TAM (2.8%) were also observed. An epimer of the trans-dG(3'P)-N:(2)-TAM N:-oxide (3.9 adducts/10(8) nucleotides) was detected as the third biggest adduct (7.2% of the total). The cis-dG(3'P)-N:(2)-TAM N:-oxide (0.4 adducts/10(8) nucleotides) accounted for 0.7% of the total. Thus, dG(3'P)-N:(2)-TAM and dG(3'P)-N:(2)-TAM N:-oxide were identified in tamoxifen-treated mouse liver.

Animals↗

PubMed2000

Vitamin B6 supplementation can improve peripheral polyneuropathy in patients with chronic renal failure on high-flux haemodialysis and human recombinant erythropoietin.

BACKGROUND: High-flux haemodialysis (HD) has recently been vigorously promoted as a novel standard, and it can indeed efficiently reduce the occurrence of most uraemic symptoms due to middle molecular toxins and/or underdialysis. However, some symptoms remain problematical, particularly peripheral polyneuropathy (PPN). One of the possible reasons for this is that the patients may have low concentrations of some nutrients, e.g. vitamin B(6), necessary for normal peripheral neuron function. METHODS: Predialysis serum pyridoxal-5'-phosphate (P5P) level was determined in 36 chronic HD patients who were undergoing high-flux HD and receiving human recombinant erythropoietin. Among them, 26 patients suffered from PPN. Prior to supplementation, these 26 patients were examined and their neurological symptoms were ranked according to our PPN symptom score. Vitamin B(6) (60 mg/day) was randomly prescribed to 14 of them, and vitamin B(12) (500 microg/day) was prescribed to the others. After 4 weeks, all the patients were re-examined. RESULTS: We found that predialysis serum P5P levels of HD patients with PPN were not significantly lower than those of matched HD patients without PPN. Nonetheless, it was demonstrated that supplementation with vitamin B(6) for 4 weeks significantly increased the predialysis level of P5P and dramatically attenuated PPN symptoms compared with initial symptoms. No improvement was observed in response to vitamin B(12) supplementation. CONCLUSION: This result suggests that although vitamin B(6) deficiency could not be demonstrated in patients with chronic renal failure on high-flux HD, vitamin B(6) supplementation was effective in improving PPN symptoms of various aetiologies, possibly because of vitamin B(6) resistance to PPN in these patients.

Chronic Disease↗

PubMed2000

Zinc-finger genes that specifically express in pistil secretory tissues of petunia.

Tissue-specific expression patterns of petunia zinc-finger genes, ZPT2-10 and ZPT3-3, were analyzed by using GUS reporter system. The GUS expression directed by ZPT2-10 promoter was specifically found in the stylar transmitting tissue of pistil, and that by ZPT3-3 promoter in stigmatic and stylar transmitting tissues. These tissues play important roles in reproductive process. We discuss possible roles of the zinc-finger proteins in these specialized tissues.

Base Sequence↗

PubMed2000

Standards for the evaluation of hospital infection control policies and procedures.

Explore the source record for details and available documents.

Cross Infection↗

PubMed2000

Glucocorticoid restores the deterioration of water transport in the peritoneum through increment in aquaporin.

This study was carried out to investigate the role of aquaporin (AQP) in the peritoneum undergoing continuous ambulatory peritoneal dialysis (CAPD). Furthermore, we examined the effects of treatment with prednisolone (PSL) in a rat model of peritoneal sclerosis. We modelled peritoneal sclerosis by using dialysis solution with the addition of 0.1% chlorhexidine gluconate (CHG) for 10 days. Twenty male Wistar Kyoto (WKY) rats were divided into four groups and dialyzed with various solutions: (1) saline (NS group, n = 5); (2) 10% glucose (TZ group, n = 5); (3) 0.1% CHG (CHG group, n = 5); and (4) 0.1% CHG plus PSL (CHG + PSL group, n = 5). Expression of mRNA of AQPs (AQP-1-AQP-4) was studied by semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR). Expression of AQP-4 was also measured by Western blot analysis. Ultrafiltration volume and peritoneal function were measured by the peritoneal equilibration test. In the TZ group, expression of AQP-1 and AQP-4 were significantly enhanced, in parallel with an increment in ultrafiltration volume. On the other hand, in the CHG group, expression of AQP-1 and AQP-4 were significantly suppressed, and ultrafiltration volume was lost. The use of PSL with CHG completely restored the expression of AQP-1 and AQP-4, and peritoneal function improved. No expression of AQP-2 and AQP-3 was seen in the peritoneum. Our results suggest that AQP-1 and AQP-4 may be important factors in water transport in patients undergoing CAPD. PSL might be an effective treatment to prevent the progress of peritoneal sclerosis in patients undergoing CAPD.

Animals↗

PubMed2000

Vitamin B6 deficiency in elderly patients on chronic peritoneal dialysis.

Polyneuropathy is one of the most frequent manifestations in chronic uremia. Among the factors related to polyneuropathy, vitamin B6 deficiency is well known. The exact prevalence of vitamin B6 deficiency related to neurological manifestations has not been previously reported. We studied vitamin B6 status, collected self-reported symptoms, and carried out full neurological examinations in 66 patients on chronic peritoneal dialysis. Vitamin B6 status was estimated by direct measurement of pyridoxal phosphate. In general, symptoms related to vitamin B6 deficiency are peripheral neuropathies, such as paresthesia, burning and painful dysesthesias, and thermal sensations. These symptoms were reported and assigned one of five grade scores. Of our 66 patients, 12 patients complained at least one sensory abnormality. The levels of vitamin B6 in the patients varied between 1.0 ng/mL and 30 ng/mL. Patients who complained of neurological symptoms owing to vitamin B6 deficiency were significantly older than the other patients. In analyzing the symptomatic cases before and after vitamin B6 supplementation, a significant correlation was seen between the level of vitamin B6 and symptoms. Within one month after initiation of oral vitamin B6 supplementations (30 mg daily), levels of pyridoxal phosphate rose, and sensory abnormalities improved in 8 of 12 patients. When peripheral neuropathy is suspected in elderly patients on chronic peritoneal dialysis, vitamin B6 deficiency should be taken into consideration as the cause. If vitamin B6 deficiency is appropriately treated by oral supplementation, sensory abnormalities can be eliminated.

Adolescent↗

PubMed2000

Blood pressure reduction associated with preservation of renal function in hypertensive patients with IgA nephropathy: a 3-year follow-up.

BACKGROUND: The relative importance of hypertension in the progression of renal failure is well understood. Recently, several studies have provided evidence that antihypertensive therapy enhances renal survival. However, the specific antihypertensive drug regimens that are most effective in generating such long-term effects remain controversial. PATIENTS AND METHODS: Forty-nine hypertensive IgA nephropathy (IgAN) patients (39 +/- 7 years old, serum creatinine 1.1 +/- 0.2 mg/dl) with proteinuria received antihypertensive therapy with angiotensin-converting enzyme inhibitors (ACEi: 2.5-10 mg of benazapril daily) and calcium channel blockers (CCBs: 2.5-10 mg amlodipine daily) for 3 years. The patients' blood pressures in group one were controlled below 140/85 mmHg by increases in their first drug dose or by addition of the second drug in group 1. Blood pressures for patients in group 2 were controlled using the same two options, except to levels below 130/70 mmHg. Patients within the two groups were selected and controlled with regard to sex, age, and serum creatinine. The renal protective effects of each protocol were evaluated in terms of reductions in creatinine clearance. After 3 years of the above outlined blood pressure control regimens, the reductions in creatinine clearance were compared. RESULTS: Creatinine clearances decreased in group 1 patients (from 85.7 +/- 2.4 ml/min to 72.9 +/- 2.4 ml/min, p < 0.05). On the other hand, creatinine clearance remained essentially unchanged for patients in group 2 (from 87.2 +/-4.7 ml/min to 85.9 +/- 5.9 ml/min). Although creatinine clearance in both groups was almost the same at the start of study, there was a significant difference between them by the conclusion of the study (p < 0.05). Proteinuria and hematuria did not change significantly throughout the study and there were no significant differences in these respects between these two corresponding groups. There were no significant differences between the groups with reference to side-effects or complications. CONCLUSION: These data provide evidence that reducing blood pressure has protective renal effects in cases of mild renal insufficiency with hypertension in IgA nephropathy.

Adult↗

PubMed1999

Tamoxifen-DNA adducts formed by alpha-acetoxytamoxifen N-oxide.

DNA adduct formation is assumed to be a major carcinogenic event, leading to the development of endometrial cancer in breast cancer patients taking tamoxifen and healthy women enrolled in a tamoxifen chemopreventive trial. To determine whether DNA adducts were formed by tamoxifen, trans- and cis-alpha-acetoxytamoxifen N-oxides were synthesized as model-activated forms via major tamoxifen metabolites, tamoxifen N-oxide and alpha-hydroxytamoxifen N-oxide. When alpha-acetoxytamoxifen N-oxide was reacted with human DNA, at least three DNA adducts were detected by (32)P-postlabeling coupled with HPLC. The total amount of DNA adducts formed by trans-alpha-hydroxytamoxifen N-oxide was 1.5-fold higher than that formed by the cis form. Both trans- and cis-alpha-acetoxytamoxifen N-oxide reacted with 2'-deoxyguanosine, resulting in the formation of three adducts (fr-1, fr-2-1, and fr-2-2). These products were studied using mass spectroscopy and proton magnetic resonance spectroscopy. fr-1 was identified as a mixture of the epimers of trans-alpha-(N(2)-deoxyguanosinyl)tamoxifen N-oxide. fr-2-1 and fr-2-2 were determined to be epimers of cis-alpha-(N(2)-deoxyguanosinyl)tamoxifen N-oxide.

Acetylation↗

PubMed1999

Two novel cysteine substitutions (C1263R and C1995S) of thyroglobulin cause a defect in intracellular transport of thyroglobulin in patients with congenital goiter and the variant type of adenomatous goiter.

We analyzed the thyroglobulin (Tg) gene of 2 unrelated patients with congenital goiter and the Tg gene of 2 siblings with the variant type of adenomatous goiter. The clinical characteristics of the patients with congenital goiter and the variant type of adenomatous goiter were very similar, except for serum Tg levels, which were less than 15 pmol/L in the patients with congenital goiter, but 117-181 pmol/L in the patients with the variant type of adenomatous goiter (normal, 15-50 pmol/L). The tissue content of Tg in the thyroid glands of all 4 patients was reduced at 0.9-3.8% of total protein (normal, 19-40%). The missense mutation C1263R was detected in the 2 unrelated patients with congenital goiter; the pedigree study showed an autosomal recessive pattern of inheritance. In the 2 siblings with the variant type of adenomatous goiter, the missense mutation C1995S was homozygously detected. In the Tg complementary DNA of 110 normal subjects, the allelic frequencies of the C1263R and C1995S mutations were each less than 0.5%. Also in the normal subjects were detected 35 nucleotide polymorphisms, the insertion of 3 nucleotides, and 1 alternative splicing, each of which was not associated with any specific thyroid disease. From these data, the molecular mechanism of the C1263R and C1995S mutations was elucidated. We first analyzed the carbohydrate residues of C1263R Tg and C1995S Tg. Sensitivity to treatment by endoglycosidase H suggests that C1263R Tg and C1995S Tg were retained in the endoplasmic reticulum (ER). Also, the presence of endoglycosidase H-resistant Tg as well as endoglycosidase H-sensitive Tg in the patients with the variant type of adenomatous goiter suggests that a fraction of C1995S Tg was transported to the Golgi and associated with the mildly increased serum Tg levels. Native PAGE and Western blot analysis with anti-Tg antibody showed that C1263R Tg and C1995S Tg form high mol wt aggregates in the ER. Our results suggest that missense mutations that replace cysteine with either arginine or serine cause an abnormal three-dimensional structure of Tg. Such misfolded Tg polypeptides are retained in the ER as high mol wt aggregates.

Adenoma↗

PubMed1999

Etretinate therapy for papuloerythroderma.

Papuloerythroderma, first reported by Ofuji et al. (1984), is a rare cutaneous disorder whose pathogenesis remains unknown. Owing to the small number of cases, there is no recommended choice of treatment. This is the first report on the efficacy of etretinate for papuloerythroderma. Seven male cases ranging in age from 65 to 84 years were treated with moderate doses (0.2-0.6 mg/kg/day) of etretinate. All but one case showed quick and excellent responses and the chronic recalcitrant erythrodermatous lesions disappeared within 2-5 weeks. Eventually all the seven cases could be brought into remission. Once remission was achieved, etretinate was tapered by 0.1-0.2 mg/kg/day over a period of 2-4 weeks. One case remained in complete remission after cessation of etretinate without any treatment for 16 months. Another case could stop etretinate treatment and the subsequent recurrence of papular eruption could be managed by topical steroids. In the other five cases remission could be maintained by daily doses of 0.16-0.36 mg/kg etretinate. None of the patients developed severe side effects. Our observation suggests that etretinate is a safe and effective agent for papuloerythroderma.

Aged↗

PubMed1999

A cystatin-related gene, testatin/cresp, shows male-specific expression in germ and somatic cells from the initial stage of murine gonadal sex-differentiation.

Sex-differentiation in mammals initiates at mid-gestation when the differentiation of Sertoli cells is triggered by the expression of the testis-determining gene, Sry. However, little is known about the succeeding germ-soma interaction that directs the sex-differentiation of germ cells. We carried out subtraction and differential screening between male and female gonads at 13.5 dpc (days post coitum). A novel cystatin-related gene was identified and named cresp (cystatin-related expressed in Sertoli and spermatogonia), and has recently been reported independently under the name testatin (Töhönen et al., 1998). The presumed amino acid sequence of testatin/cresp showed considerable homology to the cystatin family, but it lacked a few critical amino acid residues for the cysteine-protease inhibitory activity. A 0.7 kb RNA was detected by northern blotting specifically in the fetal and adult testes from 11.5 dpc and expression increased between 11.5 dpc and 12.5 dpc. Using RT-PCR analysis, the testatin/cresp mRNA was first detectable at 9.5 dpc in both male and female embryos but it was maintained only in the male. In females, the expression became weaker at 11.5 dpc and was undetectable after 12.0 dpc. In situ hybridization and immunohistochemical analyses, as well as single cell RT-PCR analysis, showed that the testatin/cresp mRNA was localized specifically in both the (pro)spermatogonia and Sertoli cells in the testis from 12.5 dpc to adult. Thus, expression of the testatin/cresp gene is upregulated in male gonads but downregulated in females immediately after the initiation of sex-differentiation, suggesting roles in the early developmental cascade of testis such as the germ-soma interaction.

Amino Acid Sequence↗