LncRNA HOXA-AS2 regulates microRNA-216a-5p to promote malignant progression of non-small cell lung cancer.

OBJECTIVE: Previous studies have shown that long non-coding RNA (lncRNA) HOXA-AS2 is a cancer-promoting gene. However, the role of HOXA-AS2 in non-small cell lung cancer (NSCLC) has not been reported. This study aims to investigate the expression characteristics of HOXA-AS2 in NSCLC and whether HOXA-AS2 can promote the malignant progression of NSCLC by regulating microRNA-216a-5p. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to examine the HOXA-AS2 level in 40 pairs of NSCLC tumor tissue samples and adjacent ones. Then, the relationship between HOXA-AS2 expression and clinical indicators and prognosis of NSCLC was analyzed. Meanwhile, qRT-PCR further verified the expression level of HOXA-AS2 in NSCLC cell lines. Also, HOXA-AS2 knockdown and overexpression models were constructed using lentivirus in NSCLC cell lines, and the effects of HOXA-AS2 on the biological function of NSCLC cells were analyzed using the Cell Counting Kit-8 (CCK-8), transwell migration, and cell wound healing assays. Finally, Western blotting assay and cell recovery experiment were used to explore the regulatory mechanism of HOXA-AS2 and microRNA-216a-5p in NSCLC. RESULTS: In this experiment, qRT-PCR results revealed that HOXA-AS2 level in NSCLC tumor tissue specimens was remarkably higher than that in adjacent tissues. Compared with those with low expression of HOXA-AS2, the patients with high expression had a higher incidence of distant metastases and a lower overall survival rate. The proliferative and metastasis abilities of the cells in the HOXA-AS2 overexpression group were remarkably increased when compared with the control group, while the opposite results were observed in HOXA-AS2 silence group. Subsequently, qRT-PCR verified that microRNA-216a-5p level was remarkably decreased in NSCLC tissues and negatively correlated with HOXA-AS2 expression. In addition, the result of the cell recovery experiment and Western blotting revealed that there might be a mutual regulation between HOXA-AS2 and microRNA-216a-5p, the two of which could jointly regulate the malignant progression of NSCLC. CONCLUSIONS: The results indicate that lncRNA HOXA-AS2 is upregulated in NSCLC and is remarkably associated with distant metastasis and poor prognosis of NSCLC patients. In addition, lncRNA HOXA-AS2 is found to be able to promote the malignant progression of NSCLC via regulating microRNA-216a-5p.

Research on miR-126 in glioma targeted regulation of PTEN/PI3K/Akt and MDM2-p53 pathways.

OBJECTIVE: To study the correlations of micro ribonucleic acid (miR)-126 expression with pathogenesis and prognosis of glioma, and to screen potential biological targets for the diagnosis, treatment and prognosis of glioma. PATIENTS AND METHODS: miR-126 expression in cancer tissues, normal brain tissues, U87MG cells and normal astrocytes in glioma patients was quantitatively analyzed via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). U87MG cells were transfected with miR-126 mimics or miR-126 inhibitor, followed by verification via qRT-PCR. The cell proliferation, apoptosis, migration and invasion after transfection were analyzed using methyl thiazolyl tetrazolium (MTT) assay, Annexin V/propidium iodide (PI) assay, wound healing assay and transwell assay, respectively. The expression levels of proteins related to phosphatase and tensin homolog deleted on chromosome ten/phosphatidylinositol 3-kinase/protein kinase B (PTEN/PI3K/Akt) pathway and double mouse minute 2 homolog (MDM2)-p53 pathway were detected via Western blotting. Moreover, the prognostic analysis was performed using the Kaplan-Meier method and log-rank test. RESULTS: Results of qRT-PCR showed that the miR-126 expression in highly malignant glioma tissues and U87MG cells were significantly lower than those in normal brain cells, and its expression level was significantly higher or lower than that in negative control group after transfection with miR-126 mimics or inhibitor. Analyses of cell proliferation, apoptosis, migration and invasion revealed that the up-regulation of miR-126 could remarkably inhibit the in-vitro proliferation, migration and invasion and promote apoptosis of glioma cells, and vice versa. Results of Western blotting manifested that after overexpression of miR-126, PI3K, p-Akt and MDM2 protein levels in U87MG cells were significantly decreased compared with those in control group, but PTEN and p53 protein expressions were significantly increased, and vice versa. Besides, according to prognostic analysis, the prognosis of patients with a low miR-126 level was poorer. CONCLUSIONS: The miR-126 expression is abnormally low in glioma cells, and miR-126 inhibits the course of glioma through targeted regulation of PTEN/PI3K/Akt and MDM2-p53 pathways, which, therefore, can be used as a new potential biomarker for the diagnosis, treatment and prognosis of glioma.

[Expression of eosinophils and IL-33 levels in peripheral blood of patients with allergic rhinitis].

Objective:To investigate the relationship between the count of eosinophils(EOS) in peripheral blood and the serum levels of IL-33, and to discuss the relations among serum levels of IL-33, the count of EOS, visual analog scale (VAS) in different groups.Method:According to different treatments, the patients are divided into three groups: the untreated allergic rhinitis (AR) group (group A), the AR group who had been treated subcutaneous imunotherapy (SCIT) for at least a year (group B) and the AR complicated with allergic asthma group who had been treated subcutaneous imunotherapy (SCIT) for at least a year (gourp C). All subjects were conducted blood cell analysis, and EOS were counted. The serum levels of IL-33 were measured by enzyme linked immune (ELISA), and the obtained date were analysed by GraphPad.Prism 5.0 and SPSS 22.0.AR patients were asked to fill out VAS and were assessed nasal symptoms.Result:The serum levels of IL-33 in the group A were higher than that in other subjects (P<0.05).The serum levels of IL-33 in the group B showed no significant difference between the group B and the group C (P> 0.05).The serum levels of IL-33 in the group B were higher than that in the control group (P<0.05).The serum levels of IL-33 in the group C were higher than that in the control group (P<0.05).The count of EOS in the group A were higher than that in other subjects, and there is no difference between with each other (P> 0.05).The VAS in the group A were higher than that in the group B (P<0.05) and there is no significant difference between the group A and the group C (P<0.05).There is no difference between the group B and the group C(P<0.05).After at least one-year SCIT, the symptoms of AR patients were obviously relieved, such as consciously rhinobyon, rhinorrhea, sneezing and so on. Spearman test showed the serum levels of IL-33 in the AR patients has a weak correlation with the count of eosinophils (P> 0.05, r=0.287).Conclusion:SCIT is an effective treatment for AR patients. role on AR, which can alleviate the symptoms of patients, also can reduce the levels of IL-33 and the count of EOS in peripheral blood.

[Clinical features of liver cirrhosis complicated by portal vein thrombosis and related risk factors].

Objective: To investigate the clinical features of patients with liver cirrhosis complicated by portal vein thrombosis (PVT) and related risk factors. Methods: A total of 65 patients with liver cirrhosis complicated by PVT who were diagnosed and treated from June 2013 to June 2015 were enrolled as PVT group, and 70 cirrhotic patients without PVT were enrolled as controls (non-PVT group). The data collected included general information, results of laboratory examination, imaging findings, clinical manifestations, and complications. The clinical features were compared between the two groups, and related risk factors were screened out. Results: There were no significant differences between the PVT group and non-PVT group in age, sex, nation, etiology, white blood cell count, platelet count, international normalized ratio, activated partial thromboplastin time, fibrinogen, serum creatinine, total bilirubin, and the diameter of the splenic vein (all P > 0.05), while between these two groups, there were significant differences in D-dimer (1.87±1.45 mg/ml vs 0.55±0.58 mg/ml, P < 0.05), fibrinogen degradation product (FDP) level (18.57±19.46 µg/ml vs 5.45±6.00 µg/ml, P < 0.05), hemoglobin (99.32±26.73 g/L vs 112.64±25.03 g/L, P < 0.05), albumin (28.51±5.19 g/L vs 33.07±7.94 g/L, P < 0.05), the diameter of the portal vein (12.53±2.70 mm vs 11.17±1.79 mm, P < 0.05), spleen thickness (5.12±0.95 cm vs 4.56±0.83 cm, P < 0.05), spleen length (15.35±3.21 cm vs 13.86±2.82 cm, P < 0.05), and Child-Pugh score (7.66±2.06 vs 6.93±1.87, P < 0.05). The two groups showed no significant differences in diarrhea, ileus, hepatorenal syndrome, and hepatic encephalopathy (P > 0.05), but showed significant differences in abdominal pain (18 vs 7 cases, P < 0.05), fever (17 vs 4 cases, P < 0.05), esophageal variceal bleeding (22 vs 9 cases, P < 0.05), and spontaneous peritonitis (24 vs 12 cases, P < 0.05). D-dimer (OR = 4.290, P < 0.000) and mean platelet volume (OR = 1.294, P = 0.023) were independent risk factors for PVT in patients with liver cirrhosis. Conclusion: Cirrhotic patients with a high degree of liver cirrhosis, high levels of D-dimer and FDP, and a large diameter of the portal vein tend to have a high incidence rate of PVT. PVT can aggravate the clinical symptoms and significantly increase complications in patients with liver cirrhosis. An increased D-dimer level and a greater width of the main portal vein are independent risk factors for PVT in patients with liver cirrhosis.

Single- and dual-wavelength photodetectors with MgZnO/ZnO metal-semiconductor-metal structure by varying the bias voltage.

By varying the bias voltage of an Mg x Zn1-x O/ZnO metal-semiconductor-metal photodetector (MSM-PDs), the detection wavelength can be modulated from a single to a dual wavelength. A long-wavelength band response is caused by the ZnO absorption and a short-wavelength band response is caused by Mg x Zn1-x O. At a 0 V bias voltage, the photogenerated electrons in ZnO are confined to the Mg x Zn1-x O/ZnO interface, arising from the piezoelectric polarization. The accumulated electrons hop the Mg x Zn1-x O layer through the assistance of defects; however, the photogenerated electrons in Mg x Zn1-x O cannot cross over the large barrier height at the Au/MgZnO interface, resulting in a single-wavelength photodetector with a long-wavelength band (345-400 nm) having a peak wavelength of 370 nm. By increasing the bias voltage to 1-2 V, the barrier height is lowered, enabling the photogenerated electrons in Mg x Zn1-x O to easily cross over the low barrier height, leading to dual-wavelength photodetectors having peak wavelengths of 370 and 340 nm. On further increasing the bias voltage beyond 2 V, the photogenerated electrons in ZnO sink deeply in the hollow at the Mg x Zn1-x O/ZnO interface owing to the large applied voltage. These electrons are effectively confined at the Mg x Zn1-x O/ZnO interface, which retards the tunneling of the photogenerated electrons in ZnO through the Mg x Zn1-x O layer; hence the MSM-PDs revert back to single wavelength photodetectors; however, the detection wavelength is different from that of the MSM-PDs biased at 0 V. Instead of having a long-wavelength band (345-400 nm), the MSM-PDs demonstrate a short-wavelength band (320-345 nm) at a 3 V bias voltage.

Transplantation of embryonic stem cell-derived cardiomyocytes improves cardiac function in infarcted rat hearts.

BACKGROUND: Post-infarct congestive heart failure is one of the leading causes of morbidity and mortality in industrialized countries. The main purpose of this study was to investigate whether transplantation of embryonic stem cell-derived cardiomyocytes (ESCM) directly into the infarcted myocardium could improve cardiac function in rats. METHODS: Cell culture medium with or without ESCM was injected into the borders of cardiac scar tissue 1 week after experimental infarction. Cardiac performance was evaluated 4 weeks later by means of echocardiography after ESCM (n=16) or medium (n=12) injection. RESULTS: ESCM implantation significantly improved fractional shortening (31.5+/-3. 8%) compared with medium-treated hearts (21.3+/-5.2%; P<0.05) and preserved left ventricular structure. Co-localization of 4',6-diamidino-2-phenylindole-labeled nuclei of transplanted cells with cardiomyocyte markers for cardiac troponin T and connexin-43, as detected by immunofluorescent microscopy, indicated the regeneration of damaged myocardium and the formation of gap junctions between grafted and host cells. However, intra-myocardial teratomas were observed in the hearts of two of the 16 grafted animals, at the fourth week after ESCM transplantation. DISCUSSION: Our results suggest that, although ESCM implantation can improve the function of infarcted myocardium, strategies to prevent tumorigenesis should be developed.

A new method for determination of parameters in sewer pollutant transformation process model.

Understanding pollutant transformation in sewers is important in controlling odor emission from pressure mains as well as in assessing organic pollutant removal capacity of gravity sewers. Sewer process models have thus been developed to quantify the pollutant transformation processes under various sewer conditions. The quantification largely depends on model parameter values, in particular the kinetic and stoichiometric parameters related to microbial activities. The current approaches not only involve a large amount of experimental work but also may induce significant errors when microbial reactions cannot be differentiated effectively during the experiments. Therefore, this study is aimed at developing a new method that can reduce experimental work significantly. The proposed method utilizes a genetic algorithm (GA) to enable the determination with a single set of batch experiments. To study the feasibility of the proposed method, a set of 72-hr batch experiments was first conducted for determining the parameters of a sewer model developed in this study, which adopted a full version of the International Water Association (IWA) Activated Sludge Model No. 3 (ASM3) to describe the microbial activities in sewers. The results were then verified with two different sets of the batch experiments. Furthermore, dynamic variation data of dissolved oxygen level were collected at the outlet of a 1.5-km gravity sewer to validate the determined parameters. All the results showed that the proposed parameter determination method is effective.

Genetic heterogeneity in acrokeratosis verruciformis of Hopf.

BACKGROUND: Acrokeratosis verruciformis of Hopf (AKV) is a rare genodermatosis characterized by multiple flat-topped, flesh-coloured papules on the dorsa of hands and feet, and punctuate keratoses on the palms and soles. A mutation in the ATP2A2 gene has been shown to be associated with AKV and with Darier's disease (DD). OBJECTIVES: To explore the molecular aetiology of AKV and DD. METHODS: We investigated the clinical and histological information in two families and a sporadic case with AKV and one family and a sporadic case with DD in China. Mutation analysis of ATP2A2 was performed by PCR and direct sequencing, and genotyping and linkage analysis performed using six polymorphic microsatellite markers spanning the locus at 12q23-12q24 containing ATP2A2. RESULTS: Mutational analysis showed no mutation in ATP2A2 among the AKV patients, but we found two novel mutations (p.C318F and p.M719fs) in the DD patients. The genotyping and linkage analysis results revealed no linkage evidence of the locus at 12q23-12q24 in a large AKV family. CONCLUSIONS: Our findings provide evidence for the genetic heterogeneity of AKV and demonstrate that mutations in genes other than ATP2A2 are responsible for AKV in a proportion of the Chinese population.

The genetic epidemiology of alopecia areata in China.

BACKGROUND: Alopecia areata (AA) is hypothesized to be an organ-specific autoimmune disease with genetic predisposition and an environmental trigger. There are few clinical data in Asians. OBJECTIVES: To describe the genetic epidemiological features of AA patients in China and to determine the possible genetic model for AA. METHODS: Data for 1032 patients with AA were obtained by questionnaire in the Institute of Dermatology of Anhui Medical University in China from 2001 to 2003. Complex segregation analysis and heritability analysis were performed using Falconer's method, EPI INFO 6.0 and SAGE-REGTL programs. RESULTS: In total, 1032 AA patients (male/female ratio 1.1 : 1) were enrolled, representing 0.94% of the total number of cases seen in our outpatient clinic during that time. The mean +/- SD age of onset was 28.98 +/- 13.43 years. The difference between the mean age of onset in males and females was not significant. Most patients (82.6%) experienced their first episode of AA within the first four decades of life. A positive family history of AA was obtained in 87 patients (8.4%). The prevalence of AA in first-, second- and third-degree relatives of the proband with AA was 1.6%, 0.19% and 0.03%, respectively. These figures were higher than those in controls. A greater severity and longer duration of AA were seen in the early onset group than in the late-onset group. The early onset group also had more affected first- and second-degree relatives. The heritability of AA in first-, second- and third-degree relatives was 47.16%, 42.53% and 22.29%, respectively. Based on the REGTL results, the best model was a polygenic additive model for AA. CONCLUSIONS: The effect of genetic factors is strong in AA, but environmental factors such as infection and psychological stress may still play an important role. Our findings on the genetics of AA are consistent with a polygenic additive mode of inheritance.

Pattern of Doppler flow indices at the carotid bifurcation: evaluation by hemodynamic color Doppler imaging.

OBJECTIVE: To visualize the spatial variation of Doppler indices, principally the pulsatility index, taken proximal to the carotid bifurcation and to evaluate their relationship to the geometry of the carotid bulb. METHODS: The pattern of ultrasonographic Doppler indices was studied in healthy volunteers by using hemodynamic color Doppler imaging, which computes and displays a Doppler index at each color pixel from a sequence of color Doppler image frames taken over several cardiac cycles. RESULTS: In carotid bulbs with laminar flow (n = 5), the spatial partitioning between low-resistance internal carotid artery and high-resistance external carotid artery flows could be followed over 5 cm upstream in the common carotid artery. However, normal reverse or vortex flows at the carotid bulb (n = 15) obliterated upstream flow partitioning within 2 cm of the flow divider The pulsatility index was neither laterally nor axially uniform in the common carotid artery. CONCLUSIONS: Localization of "core flow" where meaningful Doppler indices may be measured is determined by the expansion geometry of the carotid bulb and usually requires positioning of a small sample volume in the center of the lumen at least 3 cm upstream from the flow divider However, in the absence of reverse or vortex flows, placement of a spectral Doppler sample volume is best guided by hemodynamic color Doppler imaging.

X-linked Charcot-Marie-Tooth disease and connexin32.

X-linked Charcot-Marie-Tooth disease is caused by mutations in the gene for the gap junction protein connexin32. This protein is expressed in peripheral nerve and present in noncompacted myelin, where it likely forms channels around and across the myelin sheath. Studies in cell culture and in transgenic mice show that connexin32 mutations can cause a loss of channel function or a gain of toxic effects on myelinating Schwann cells or both, with resulting peripheral nerve degeneration.

Hemodynamic imaging with pulsatility-index and resistive-index color Doppler US.

Pulsatility index and resistive index were mapped with color Doppler ultrasound (US) and compared with spectral Doppler US findings. In the carotid arteries and/or kidneys in 12 healthy subjects, the pulsatility index and resistive index were estimated from mean frequency shifts and mapped into "cool-warm" or "rainbow" color scales. Surveys that depicted intervessel variations in a complex vascular field were useful in deciding where to perform spectral Doppler US. Intravessel variations were consistent with fluid dynamic theory.

Mouse Eotaxin expression parallels eosinophil accumulation during lung allergic inflammation but it is not restricted to a Th2-type response.

A model of lung eosinophilia based on the repeated exposure of mice to aerosolized OVA has been used to identify C-C chemokine genes expressed at stages of massive eosinophil infiltration. We describe the identification and cloning of a cDNA that encodes a mouse C-C chemokine with 68% amino acid identity to guinea pig Eotaxin. The recombinant protein encoded by this gene displays potent and specific chemotactic activity for eosinophils, both in vivo and in vitro. Its mRNA levels parallel the kinetics of eosinophil accumulation in the lung during the experimentally induced eosinophilia and it is mainly produced by type I alveolar epithelial cells. The mRNA expression of mouse Eotaxin is not restricted to Th2 T cells in vitro and is independent of the development of a Th2-type response during N. brasiliensis infection, in vivo.

3-beta-D-ribofuranosyl-6,7-dihydro-9H-thiazolo[3,2-a]purin-9-one hydrate.

The title molecule, C12H14N4O5S.H2O (I), has a syn-XCN glycosyl torsion angle, which is stabilized by an intramolecular hydrogen bond between N3 of the tricylic base and O5' of the ribose (in a C2'-endo pucker). [The purine base, including atoms S and O6, of the molecule is planar to within 0.043 (2) A.] The tricyclic bases are stacked along a with an interplanar distance of 3.602 (3) A.

Unusual conformational flexibility in N1-substituted uncommon purine nucleosides. Crystal structure of 1-allyl-isoguanosine and 1-allyl-xanthosine.

Several new N1-substituted uncommon purine nucleosides, including doridosine (1-methyl-isoguanosine; m-iG), 1-allyl-isoguanosine (a-iG) and 1-allyl-xanthosine (a-X), have been synthesized and tested as agonists for the adenosine receptors. Some have smooth muscle relaxant or negative chronotropic activities. The X-ray crystal structure of these compounds has been determined at atomic resolution in order to understand the structure-activity relationship. The structures were solved by direct methods and refined by full-matrix least-squares refinement procedure. The crystallographic parameters are: a-iG, space group P2(1), a = 10.573 (1) A, b = 21.955 (2) A, c = 14.360 (1) A, beta = 110.65 (1) degree, no. of 3 sigma Fo's = 4585, R = 0.047; a-X, space group P2(1)2(1)2(1), a = 16.015 (2) A, b = 16.239 (1) A, (1) A, c = 5.3723 (5) A, no. of 3 sigma Fo's = 1169, R = 0.031. In the a-iG crystal, there are 4 independent molecules (with different conformation) per asymmetric unit. While all 4 molecules adopt anti chi CN glycosyl torsion angle, their riboses have 3 distinct puckers (C2'-exo, C2'-endo and C1'-exo). In contrast, the a-X structure adopts a syn chi CN glycosyl torsion angle, which is stabilized by an intramolecular hydrogen bond between the N3 of purine base and the O5' of the ribose (in C2'-endo pucker). Both purine bases (a-iG and a-X) are mainly in the keto tautomer form. For the isoguanine base, the averaged N1-C2 bond distance (1.42 A) is significantly longer than that (1.375 A) of the guanine base. For the xanthine base, N3 nitrogen has an imino proton attached which is unambiguously located in the electron density map. The surprising flexibility in the ribose ring of these N1-substituted uncommon purine nucleosides suggests that the ribose moiety may not participate in the binding of nucleoside to the adenosine receptors.

A new strategy of iontophoresis for hyperhidrosis.

We used a modified iontophoretic method with an anticholinergic agent and aluminum chloride to treat hyperhidrosis. The strategy behind this combination was to shift gradually from inhibition of sweat gland secretion to blockage of the sweat duct. In a double-blind study in which we compared our method with tap water iontophoresis, the results were comparable. A second study revealed an 87% response rate, with an average remission period of 32 days. Our data indicate that patients who were older at onset, had a family history negative for the disorder, had an early response, or underwent treatment in cool weather had the most favorable results.

Keratitis, ichthyosis, and deafness (KID) syndrome with cerebellar hypoplasia.

A 6-year-old boy with features of the keratitis-ichthyosis-deafness (KID) syndrome and cerebellar hypoplasia is the second case in which abnormality of cerebellum was detected by computed tomography, but is the first report of KID syndrome with cerebellar hypoplasia. This finding, together with neurosensory deafness and other neuromuscular defects, may suggest that there is an underlying inborn error of nervous system in the KID syndrome. In vitro immunologic studies in this patient also showed a possible deficit in cellular immunity.

Pattern of cancer in Saudi Arabs referred to King Faisal Specialist Hospital.

A total of 7251 histologically confirmed new cases of cancer (4117 males and 3134 females) were seen in the 6-year period 1979 to 1984 at the King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia. The crude relative frequencies of cancer at various primary sites have been determined with reference to sex, age, geographic origin, and year of diagnosis. The most common cancer sites among males were non-Hodgkin's lymphomas, esophagus, lung, liver, stomach, and nasopharynx. Breast cancer was the most common tumor among the females, followed by non-Hodgkin's lymphomas and cancers of the thyroid, esophagus, cervix, and ovary. The most marked deviations were found in the Southern Region for cancers of the oral cavity (2.4 times higher), bladder (1.8 times higher), and lung (4.3 times lower). Known etiologic factors, such as local chewing, smoking habits, and schistosomiasis are likely to be responsible for these differences. Upward trends in cancers of lung, breast, colon and rectum, and the downward trend in esophageal cancer may reflect the rapid pace of modernization.

Inhibition of DNA and protein synthesis and cell division by photoactivated haematoporphyrin derivative in hamster ovary cells.

Experiments were performed on cultured Chinese hamster ovary cells exposed to haematoporphyrin derivative (HpD) plus light, yielding survival rates of 40-100%. [3H]-thymidine, [3H]-tryptophan and [14C]-lysine incorporation were used to quantitate DNA and protein synthesis in surviving cells after exposure. Multiple experiments demonstrated 78% reduction in DNA synthesis during the first day after exposure to 20 micrograms ml-1 HpD plus 1140 Jm-2 light followed by progressive recovery to the normal rate after 4-6 days. Protein synthesis was somewhat less sensitive dropping by 54% initially and fully recovering by day 4. Although this cell line has a normal cycle time averaging approximately 15 h, cell division was rarely observed among lone surviving cells until 72 h after exposure. No inhibition was observed in cells exposed to HpD in the dark. These results indicate that photoactivated HpD has a wide spectrum of reversible nuclear and cytoplasmic effects even at sublethal doses. This is consistent with the notion that clinical photodynamic therapy is not likely to result in chronic morbidity.