aex-3 encodes a novel regulator of presynaptic activity in C. elegans

C. elegans aex-3 mutations cause pleiotropic behavioral defects that are suggestive of reduced synaptic transmission. aex-3 mutations also show strong genetic interactions with mutations in unc-31 and unc-64, two other genes implicated in synaptic transmission. Physiological and pharmacological studies indicate that aex-3 defects are presynaptic. In aex-3 mutants, the synaptic vesicle-associated RAB-3 protein aberrantly accumulates in neuronal cell bodies and is reduced in synapse-rich axons. This localization defect is specific to RAB-3, since other synaptic proteins are localized normally in aex-3 mutants. aex-3 encodes a 1409 amino acid protein with strong homology to DENN, a human protein of unknown function. In C. elegans, aex-3 is expressed in all or nearly all neurons. These results suggest that AEX-3 is a novel regulator of presynaptic activity that interacts with RAB-3 to regulate synaptic vesicle release.

Use of serum creatine kinase MM isoforms for predicting the progression of left ventricular dilation in patients with hypertrophic cardiomyopathy

Serum creatine kinase (CK) isoforms were examined to detect the progression of left ventricular (LV) enlargement with reduced motion, resembling dilated cardiomyopathy (DCM), in hypertrophic cardiomyopathy (HCM). Changes in LV indices were determined annually by echocardiography in 51 patients until serum measurements (first follow-up period, 6.5 +/- 2.2 years). Serum creatine isoforms (CKMM1, CKMM2 and CKMM3) were measured with high-voltage electrophoresis in 35 of these patients from 1991 to 1992, and the data for these latter patients are reported here. Serum total CK, CKMB, lactate dehydrogenase and its isoenzyme LDH1 were also measured. The changes in LV indices were further monitored until January, 1995 (second follow-up). During the 2 follow-up periods, the patients in the on-going group showed a reduction in the LV ejection fraction (LVEF) to < 55% with LV end-diastolic dimension (LVDd) < 55 mm, and those in the DCM-like group showed a reduction in LVEF to < 55% and an increase in LVDd to > 55 mm. During the first follow-up period, LVEF and LVDd remained at > or = 55% and < 55 mm, respectively, in 26 patients (nonprogressive-disease group), while 3 patients entered the on-going group and 6 entered the DCM-like group. The CKMM3/CKMM1 ratios in the on-going and DCM-like groups were significantly higher than those in the control and nonprogressive-disease groups. The CKMM3/CKMM1 ratio was significantly correlated with the annual rate of change for the LV end-systolic dimension (LVDs), LVDd, and LVEF, with the closest correlation observed for the annual change in LVDs. Moreover, 5 patients in the nonprogressive-disease group with elevation of the CKMM3/CKMM1 ratio to > + 2SD above the mean for the controls had an elevated annual change in LVDs within +/- 1SD of the mean in the DCM-like group. These results indicate that the ratio of CKMM3 to CKMM1 can be used to predict the progression of LV enlargement in HCM.

Genetics in rhythm

Rhythmic phenomena are widespread in biology. Genetic analysis of 24 hour circadian rhythms has a long history, and recent studies of circadian clock genes in Drosophila and Neurospora provide insight into clock mechanisms, including rhythm generation, clock setting by external signals and temperature compensation of rhythm. Faster biological rhythms, called ultradian rhythms, vary widely in periodicity and are likely to be generated by diverse mechanisms. In animals, ultradian rhythms are important in many neuromuscular systems, such as heartbeat, peristalsis and breathing. Recent progress has been made in the genetic analysis of heartbeat in humans and an ultradian rhythm controlling defecation in Caenorhabditis elegans.

Expression of parathyroid hormone-related peptide in human osteoarthritis

To evaluate the involvement of the expression of parathyroid hormone-related peptide gene in human articular cartilage pathology, we performed immunohistochemical staining and in situ hybridization on specimens of femoral head cartilage obtained from 15 patients with osteoarthritis, 11 with rheumatoid arthritis, and 12 control subjects. Parathyroid hormone-related peptide-positive chondrocytes were observed predominantly in degenerated lesions of osteoarthritic tissue and were less evident in rheumatoid arthritic samples, while the normal cartilage expressed little parathyroid hormone-related peptide. In addition, the level of parathyroid hormone-related peptide expression was clearly dependent on the degree of cartilage degeneration; cartilage tissues with moderate degenerative changes contained more positive chondrocytes compared with mildly or severely degenerated cartilage. In situ hybridization confirmed the localization of parathyroid hormone-related peptide protein and demonstrated intense expression of mRNA of the peptide in osteoarthritic samples. This is the first demonstration of parathyroid hormone-related peptide expression in chondrocytes from pathologic articular cartilage of humans. Our results suggest that parathyroid hormone-related peptide may be involved in the pathophysiology of osteoarthritis.

Interactions between vitamin E homologues and ascorbate free radicals in murine skin homogenates irradiated with ultraviolet light

The mechanism of oxidation of ascorbic acid in mouse skin homogenates by UV light was investigated by measuring ascorbate free radical formation using electron spin resonance signal formation. Addition of vitamin E (alpha-tocopherol or alpha-tocotrienol) had no effect, whereas short-chain homologues (2,5,7,8-tetramethyl-6-hydroxychroman-2-carboxylic acid [Trolox] and 2,2,5,7,8-pentamethyl-6-hydroxychromane [PMC]) accelerated ascorbate oxidation. The similar hydrophilicity of ascorbate, Trolox and PMC increased their interaction, thus rapidly depleting ascorbate. When dihydrolipoic acid was added simultaneously with the vitamin E homologues, the accelerated ascorbate oxidation was prevented. This was due to the regeneration of ascorbate and PMC from their free radicals by a recycling mechanism between ascorbate, vitamin E homologues and dihydrolipoic acid. Potentiation of antioxidant recycling may be protective against UV irradiation-induced damage. The rate of ascorbate oxidation in the presence of vitamin E homologues was enhanced by a photosensitizer (riboflavin) but was not influenced by reactive oxygen radical quenchers, superoxide dismutase or 5,5-dimethyl-1-pyrroline-N-oxide. These experimental results suggest that the UV irradiation-induced ascorbate oxidation in murine skin homogenates is caused by photoactivated reactions rather than reactive oxygen radical reactions.

Effect of active fragments of arginine-vasopressin on the disturbance of spatial cognition in rats

The effect of arginine8-vasopressin (AVP1-9) and its metabolite C-terminal fragments on the scopolamine-induced disruption of spatial cognition were investigated using an 8-arm radial maze task in rats. AVP1-9 (10 micrograms/kg s.c.) markedly improved the disruption of spatial cognition by treatment with scopolamine (0.5 mg/kg i.p.), and 60% of the rats recovered to a normal level. The main metabolite of AVP1-9, AVP4-9 (0.5 and 1 ng/kg s.c.) also significantly improved the scopolamine-induced deficit of spatial memory. The activity of AVP4-9 was determined to be about 10000 fold greater than that of AVP1-9. An intracerebroventricular (i.c.v.) injection of 10 fg of AVP5-8, however, showed a lower activity. Both AVP6-8 and AVP5-7, which are both metabolites of AVP5-8, demonstrated no activity. The scopolamine-induced disruption of spatial memory was found to improve after a microinjection of AVP4-9 (1 fg) into the ventral hippocampus (VH) region, but not into the dorsal hippocampus (DH). In an in vivo microdialysis study, the scopolamine-induced acetylcholine (ACh) release from the VH was slightly potentiated by treatment with AVP4-9 (10 fg i.c.v.). In addition, an AVP4-9 analogue, No. 302, which is a synthetic hexapeptide and has a longer half-life, also demonstrated a markedly improved effect, which had a 10-fold higher activity than that with AVP4-9. AVP4-9 is the most potent activity of all the endogenous metabolites of the AVP1-9 and the new synthetic AVP4-9 analogue, No. 302 (obtained from Nippon Chemiphar Co.), substituting Ser for Cys-Cys in hexapeptide, has higher activity than that of AVP4-9. These results indicated [Ser6] hexapeptide has an important role in behavioral activity. Based on these results, it is possible that AVP1-9 and its metabolite AVP4-9 could, thus, be useful in treating cholinergic dysfunction diseases, such as Alzheimer's disease. Hexapeptide may play an important role in improving the spatial memory by promoting the release of ACh in the VH region.

Participation of presenilin 2 in apoptosis: enhanced basal activity conferred by an Alzheimer mutation

Overexpression of the familial Alzheimer's disease gene Presenilin 2 (PS2) in nerve growth factor-differentiated PC12 cells increased apoptosis induced by trophic factor withdrawal or beta-amyloid. Transfection of antisense PS2 conferred protection against apoptosis induced by trophic withdrawal in nerve growth factor-differentiated or amyloid precursor protein-expressing PC12 cells. The apoptotic cell death induced by PS2 protein was sensitive to pertussis toxin, suggesting that heterotrimeric GTP-binding proteins are involved. A PS2 mutation associated with familial Alzheimer's disease was found to generate a molecule with enhanced basal apoptotic activity. This gain of function might accelerate the process of neurodegeneration that occurs in Alzheimer's disease, leading to the earlier age of onset characteristic of familial Alzheimer's disease.

Requirement of the familial Alzheimer's disease gene PS2 for apoptosis. Opposing effect of ALG-3

ALG-3, a truncated mouse homologue of the chromosome 1 familial Alzheimer's disease gene PS2, rescues T hybridoma 3DO cells from T-cell receptor-induced apoptosis by inhibiting Fas ligand induction and Fas signaling. Here we show that ALG-3 transfected 3DO cells express a COOH-terminal PS2 polypeptide. Overexpression of PS2 in ALG-3 transfected 3DO cells reconstitutes sensitivity to receptor-induced cell death, suggesting that the artificial PS2 polypeptide functions as a dominant negative mutant of PS2. ALG-3 and antisense PS2 protect PC12 cells from glutamate-induced apoptosis but not from death induced by hydrogen peroxide or the free radical MPP+. Thus, the PS2 gene is required for some forms of cell death in diverse cell types, and its function is opposed by ALG-3.

Binding of tacrolimus (FK506) with human plasma proteins re-evaluation and effect of mycophenolic acid

Protein binding of tacrolimus (FK506) in human plasma was re-evaluated by equilibration dialysis and compared with that of FK506 previously reported by two different methods (about 99 and 77% by an ultrafiltration and ultracentrifugation method, respectively). The binding determined in this study was about 99% irrespective of FK506 concentrations added (0.5-10 ng/ml) and this value was very close to that estimated by the ultrafiltration method. The effect of mycophenolic acid (MPA, an active form of the immunosuppressant mycophenolate mofetil) and its glucuronide (MPAG, a major metabolite of mycophenolate mofetil in human plasma) on the binding was studied at concentration levels of 1 and 10 ng/ml of FK506. The binding was not affected significantly by the addition of MPA (25-100 micrograms/ml) and/or MPAG (100-1500 micrograms/ml). FK506 has already been reported not to cause significant changes of plasma protein binding of MPA. The results indicate that the unbound fraction of FK506 is about 1% in human plasma and that concomitant administration of FK506 and mycophenolic mofetil does not cause the drastic change of the binding of FK506 and MPA with human plasma proteins.

[Cord blood stem cell transplantation for a patient with acute myelogenous leukemia (M1)]

A five-year-old boy with acute myelogenous leukemia in relapse was treated by HLA-matched cord blood stem cell transplantation. The patient was preconditioned with 16 mg/kg of busulfan, 15 mg/kg of thiotepa and 90 mg/kg of cyclophosphamide and 2.45 x 10(7)/kg of cord blood mononuclear cells were infused to the patient on October 19th 1995 without the prophylaxis of graft-versus-host disease (GVHD). From the fifth day following the transplant, rG-CSF was administered at a dose of 300 micrograms/m2/day. Hematopoietic recovery was obtained as following; WBC over 1000/microliters was on +18 day, neutrophil over 500/microliters was on +20 day, reticulocyte over 20/1000 was on +28 day and platelet over 50 x 10(2) microliters was on +91 day. Engraftment was confirmed by DNA restriction fragment length polymorphism (VNTR) on +28 day. In spite of absence of prophylaxis of GVHD, the patient did not develop any signs of GVHD, and leukemia relapsed on +105 day. The patient died of leukemia relapse on +251 day. This is the first case of cord blood stem cell transplantation in Japan.

Parathyroid hormone-related peptide in synovial fluid and disease activity of rheumatoid arthritis

To understand the clinical role of parathyroid hormone-related peptide (PTHrP) in rheumatoid arthritis (RA), we analysed the circulatory and synovial fluid (SF) concentrations of the N- and C-terminal regions of PTHrP (N- and C-PTHrP) in RA (n = 38), osteoarthritis (OA, n = 45) and control (n = 11) subjects. The SF level of C-PTHrP was markedly higher in RA compared with control and OA groups, while no differences in circulatory C-PTHrP were present among the three groups. In contrast, the SF level of N-PTHrP was marginally higher in OA patients. C-PTHrP levels in SF correlated significantly with CRP, ESR and SF IL-1 receptor antagonist. To identify the mechanism of elevated PTHrP levels in SF, immunohistochemistry and in situ hybridization of synovial membrane (SM) were performed in each subject. Overexpression of PTHrP was identified in the sublining cells within papillary proliferated SM of RA patients only. Our results indicate that C-PTHrP produced from SM into SF reflects the disease activity in RA.

Solitary metastatic breast carcinoma in a trigeminal nerve mimicking a trigeminal neurinoma. Case report

An unusual case of a metastatic adenocarcinoma located entirely within the trigeminal nerve is reported. The patient, with a history of breast cancer, presented with a pure trigeminal mononeuropathy. The neurological and neuroradiological findings in this patient were quite similar to those of a patient with trigeminal neurinoma. Surgery revealed that the tumor was located within the trigeminal nerve and its appearance was similar to that of a neurinoma. However, histopathological studies proved the tumor to be an adenocarcinoma that was related to the breast cancer treated earlier. A solitary metastatic tumor arising solely in a trigeminal nerve is quite rare; this is the first report of such a case metastasized from breast cancer.

Parathyroid hormone-related protein (PTHrP) action in rat articular chondrocytes: comparison of PTH(1-34), PTHrP(1-34), PTHrP(1-141), PTHrP(100-114) and antisense oligonucleotides against PTHrP

Parathyroid hormone-related protein (PTHrP) is thought to be an important autocrine/paracrine factor for chondrocyte metabolism since mice lacking the PTHrP gene exhibit abnormal cartilage development. To determine the biological role of PTHrP in chondrocytes, we first compared the agonist potency of human (h) PTHrP(1-34) with hPTH(1-34) in cultured rat articular chondrocytes. Neither hPTHrP(1-34) nor hPTH(1-34) altered basal DNA synthesis, but attenuated the stimulatory effect of transforming growth factor beta (TGF-beta). Both agents suppressed the expression of alpha(1) type II collagen mRNA in a dose-response fashion with the same potency. In addition, the action of exogenously added hPTHrP(1-34) and hPTH(1-34) on intracellular cAMP and [Ca2+]i levels was similar. We next compared the effect of PTHrP within its entire amino acid sequence (1-141). With regard to thymidine incorporation, alpha(1) type II collagen gene expression and accumulation of cAMP and [Ca2+]i level, there was no significant difference between hPTHrP(1-34) and hPTHrP(1-141). PTHrP C-terminal (100-114) did not show any function. To further investigate PTHrP function, intracellular PTHrP translation was inhibited by a transgene of antisense oligonucleotides against PTHrP. Antisense oligonucleotides decreased PTHrP mRNA translation, specifically inhibited DNA synthesis in control as well as TGF-beta-treated chondrocytes and enhanced alpha(1) type II collagen mRNA expression in TGF-beta-treated chondrocytes. These results suggest that there is no significant difference between exogenously added hPTH(1-34), hPTHrP(1-34) and PTHrP(1-141) with regard to the biological action of these agents, including cell growth, differentiation and second messenger pathway. However, the result of DNA synthesis in the antisense PTHrP-inhibition study suggests that intracellular PTHrP may have an as yet unknown biological role, in addition to a classical PTH/PTHrP receptor-mediated function in the rat articular chondrocyte.

Spontaneous rupture of non-aneurysmal ascending aorta

Two autopsy cases with pericardial tamponade and spontaneous rupture of non-aneurysmal ascending aorta are described. In case 1, no apparent predisposing factor was clinically noticed in a 74 year old male patient, but postmortem examination revealed laceration of the ascending aorta associated with aortic valvular deformity and slight dilatation of the ascending aorta. In case 2, a 61 year old man, a mild to moderate grade of aortic regurgitation was noticed clinically 5 months before death. Postmortem examination revealed a slight dilatation of the aortic annulus and post-valvular portion of the ascending aorta. These two cases emphasize the clinical significance of aortic valvular disease with subsequent disordered blood flow, even when asymptomatic, as a potential causative factor for spontaneous rupture of the ascending aorta.

emo-1, a Caenorhabditis elegans Sec61p gamma homologue, is required for oocyte development and ovulation

emo-1(oz1) is a member of a class of hermaphrodite sterile mutations in Caenorhabditis elegans that produce endomitotic oocytes in the gonad arm. Oocytes in emo-1(oz1) mutants exhibit multiple defects during oogenesis. After meiotic maturation, ovulation fails, trapping oocytes in the gonad arm where they become endomitotic. emo-1 encodes a homologue of the Sec61p gamma subunit, a protein necessary for translocation of secretory and transmembrane proteins into the endoplasmic reticulum of yeast and mammalian cells. A putative emo-1 null mutation, oz151, displays embryonic lethality. The oz1 sterile mutation is a transposable element insertion into the emo-1 3' untranslated region that almost completely eliminates germline mRNA accumulation. Genetic mosaic analysis using the oz1 allele indicates that emo-1(+) expression in germ cells is required for fertility. The J67 monoclonal antibody, which recognizes an oocyte surface antigen (Strome, S. 1986. In Gametogenesis and the Early Embryo. J.G. Gall, editor. Alan R. Liss, Inc., New York. 77-95.), does not stain oz1 oocytes, a finding consistent with defective protein transport in the mutant. We propose that the emo-1 gene product acts in the transport of secreted and transmembrane proteins in C. elegans oocytes, and is necessary for both oogenesis and the coupling of ovulation with meiotic maturation.

Localisation of apoptosis and expression of apoptosis related proteins in the synovium of patients with rheumatoid arthritis

OBJECTIVES

To investigate whether apoptosis occurs in the synovium of rheumatoid arthritis (RA), and the intermediate molecules operating in this process.

METHODS

DNA fragmentation was detected by in situ nick end labelling (ISNEL) in the synovium of patients with RA (n = 11) and control patients with femoral neck fracture (n = 5). The expression of proteins p53, p21WAFI/CIPI, c-myc, proliferating cell nuclear antigen (PCNA), and Bcl-2 was also examined by immunohistochemistry.

RESULTS

ISNEL positive synovial cells with apoptosis specific morphology were detected in extremely limited areas in only two RA synovial tissue specimens. Proteins p53, p21WAFI/CIPI, and c-myc, known inducers of apoptosis or cell cycle arrest or both, were expressed in the sublining cells independent of ISNEL positive cells. PCNA, a marker for cell proliferation, was observed in the synovial lining cells. Bcl-2, an inhibitor of apoptosis, was expressed mainly in infiltrated lymphocytes and in parts of the sublining layer cells of RA; it also did not correspond with ISNEL staining.

CONCLUSIONS

Our findings indicate that RA synovial cells undergo apoptosis in addition to cell proliferation, but the frequency of apoptosis was very low. We suspect that the apoptotic process in the RA synovium may be suppressed by over-expression of Bcl-2. Although expressed proteins p53, p21WAFI/CIPI, and c-myc were present in the RA synovium, these protooncogenes are probably not implicated in the apoptotic process.

Strength of the glenoid labrum and adjacent shoulder capsule

This study evaluates the role of the glenoid labrum and capsule in the prevention of shoulder dislocation. Fifteen shoulder joints from nine fresh cadavers were used. The labrum and capsule were cut into sections 5 mm wide, and the strength of each slice to rupture was measured. The rupture site was observed microscopically. The anterior-inferior portion was the weakest, with a mean force necessary to cause rupture of 3.84 +/- 1.00 kg/5 mm. The rupture site was the portion of the labrum close to the cartilage of the glenoid. Histologic structure and degenerative changes of the labrum did not differ in the anterior to posterior portions. These results show that the anterior-inferior portion of the labrum is relatively weak. This finding may explain the lesion commonly identified in anterior shoulder dislocation.

Effects of gonadotropin-releasing hormone agonist (GnRHa) and ovariectomy on leukocyte subpopulations in rats with autotransplanted endometrium

PROBLEM

To determine the effect of estrogen deficiency on populations of immune cells in rats with autotransplanted endometrium.

METHOD OF STUDY

Autologous endometrial segments were implanted in the peritoneum of rats. Leukocyte subsets in the peripheral blood (PB) and peritoneal fluid (PF) of autotransplanted rats treated with gonadotropin-releasing hormone agonist (GnRHa) or ovariectomy were analyzed by flow cytometry.

RESULTS

Endometrial growth was suppressed in association with increases in natural killer (NK) cells and macrophages in rats treated surgically or medically after endometrial implantation compared with autotransplanted-only rats. Normal rats treated with GnRHa showed no significant alterations in PB and PF leukocyte subsets, even in NK cells and macrophages, compared with untreated normal rats.

CONCLUSIONS

Data suggest that GnRHa itself did not have an immunomodulating effect when rats were treated for 3 weeks, but that a hypoestrogenic state reduced the size of the ectopic endometrium in association with increases in NK cells and macrophages. Our findings support the hypothesis that ectopic endometrial cells may release immunosuppressive factors.

Vascular occlusion and cartilage disorders in osteonecrosis of the femoral head in rats

The aim of our study was to clarify the role of lateral epiphyseal vessels in the development of femoral head osteonecrosis in rats. We did this by performing histological and immunological studies on rats at the age that they are most prone to spontaneous osteonecrosis. We observed that obstruction of the lateral epiphyseal vessels occurred at the site of cartilage penetration. This obstruction preceded the development of osteonecrosis in adjacent areas of the femoral head. We propose that a similar mechanism may be responsible, in part, for the development of Perthes disease in man.

Localization, expression, and the role in fertilization of spermosin, an ascidian sperm trypsin-like protease

In order to elucidate the role of spermosin (a novel sperm trypsin-like protease) in ascidian fertilization, we developed an antibody against the ascidian spermosin: the antibody appears specific to the spermosin but not to the acrosin. By Western blot analysis, spermosin was found to be expressed just before and during the spawning season. Immunocytochemical studies have shown that spermosin is localized on the sperm head. It was found that the spermosin was released from the sperm during the sperm reaction, and the anti-spermosin antibody, but not control antibody, inhibited the fertilization in a concentration-dependent manner. These results indicate that spermosin plays an essential role in ascidian fertilization.

[Anesthetic management of a patient with ornithine transcarbamylase deficiency]

A 6-year-old female with disturbance of consciousness (JCS: 3 points) due to hyperammonemia caused by ornithine transcarbamylase deficiency is presented. She underwent an emergency insertion of a catheter for peritoneal dialysis under general anesthesia. Anesthesia was induced by intravenous administration of thiamylal sodium and maintained with inhalation of sevoflurane and oxygen after tracheal intubation. One percent mepivacaine was infiltrated around the surgical field to diminish the dose of sevoflurane. The operation proceeded uneventfully, although her consciousness could not recover rapidly to the normal level during the emergence from anesthesia. Peritoneal dialysis was started immediately after the operation and her consciousness recovered to the normal level gradually during the following six days with decreasing plasma ammonia levels. Ten days later, extirpation of the peritoneal catheter was scheduled. The course of anesthesia and operation was uneventful using the same anesthetic method as with the former anesthesia. In the anesthetic management for a patient with ornithine transcarbamylase deficiency, we have to be careful about the nitrogen balance, which can be affected by the kind and doses of anesthetic drugs, to avoid hyperammonemia. From this point of view, local anesthesia combined with general anesthesia might be useful to prevent the serum ammonia level from increasing.

UV-induced apoptosis in rat skin

Sunburn cells appear in the epidermis after UVB irradiation and are histologically suggested to be keratinocytes undergoing apoptosis. We here show a known biochemical process of apoptosis, genomic DNA fragmentation, in rat skin. UVB irradiation induced sunburn cells in the epidermis of rat skin at a lower dosage and the cleavage of genome DNA to nucleosomal size units at dosages of more than 0.3 J/cm2. The fragmented DNA observed could be driven from the epidermis though the involvement of DNA in dermal cells cannot be neglected. PUVA treatment also induced sunburn cells and the fragmentation of genome DNA. The extent of DNA fragmentation by UVB irradiation was enhanced depending on the dosage and peaked at 12-24 h after the irradiation. The induction of the DNA fragmentation observed in this study indicates the presence of a common pathway related to the DNA damage-induced apoptosis in the skin, and might become a useful marker in the course of in vivo studies on the physiological role of apoptotic process in the skin.