Effect of felodipine on the serum lipid profile of patients with hypertension

Forty patients suffering from mild to moderate degree of hypertension were put on felodipine. Their lipid profile was analysed before the start of their therapy and consecutively at two and four months after starting felodipine. There was a statistically significant fall in the levels of serum cholesterol, serum triglycerides and serum total lipids; though no appreciable variation was observed in HDL and LDL cholesterol levels. At baseline there were a few patients who had higher than the normal range of the serum lipid profile. Analysis of these patients showed a highly significant fall in the levels of serum cholesterol, serum triglycerides, serum LDL-cholesterol and serum total lipids i.e. felodipine modified the lipid profiles of hypertensive patients in a positive way.

The removal of acetabular bone in hip resurfacing and cementless total hip replacement

The purpose of this study was to compare the amount of acetabular bone removed during hip resurfacing (HR) and cementless total hip replacement (THR), after controlling for the diameter of the patient’s native femoral head. Based on a power analysis, 64 consecutive patients (68 hips) undergoing HR or THR were prospectively enrolled in the study. The following data were recorded intra-operatively: the diameter of the native femoral head, the largest reamer used, the final size of the acetabular component, the size of the prosthetic femoral head and whether a decision was made to increase the size of the acetabular component in order to accommodate a larger prosthetic femoral head. Results were compared using two-sided, independent samples Student’s t-tests. A statistically significant difference was seen in the mean ratio of the size of the acetabular component to the diameter of the native femoral head (HR: 1.05 (sd 0.04) versus THR: 1.09 (sd 0.05); p <  0.001) and largest acetabular reamer used to the diameter of the native femoral head (HR: 1.03 (sd 0.04) versus THR: 1.09 (sd 0.05); p < 0.001). The ratios varied minimally when the groups were subdivided by gender, age and obesity. The decision to increase the size of the acetabular component to accommodate a larger femoral head occurred more often in the THR group (27% versus 9%). Despite the emphasis on avoiding damage to the femoral neck during HR, the ratio of the size of the acetabular component to the diameter of the native femoral head was larger in cementless THR than in HR.

Verification of some building materials as gamma-ray shields

The shielding properties for gamma rays of a few low Z materials were investigated. The values of the mass attenuation coefficient, equivalent atomic number, effective atomic number, exposure buildup factor and energy absorption buildup factor were calculated and used to estimate the shielding effectiveness of the samples under investigation. It has been observed that the shielding effectiveness of a sample is directly related to its effective atomic number. The shielding character of any sample is a function of the incident photon energy. Good shielding behaviour has been verified in soil samples in the photon energy region of 0.015-0.30 MeV and of dolomite in 3-15 MeV. The results have been shown graphically with more useful conclusions.

Role of fine needle aspiration (FNA) cytology in assessment of cervical lymphadenopathy

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Background: The ability of FNA specimens to provide a definitive lymphoma diagnosis is controversial. Otolaryngolists routinely employ FNA for cervical lymph nodes which may have arisen from head and neck carcinomas, since incisional procedures may interfere with potentially curative surgery. Methods: The charts of 176 patients referred to the Kings County Hospital Center since 1996 for confirmed lymphoma were reviewed. All patients with cervical adenopathy are initially referred to the Otolaryngology service for biopsy, which is routinely FNA. Results: Of the 123 patients for whom pathological data was available, 37 had initial FNAs; 10 more FNAs (total 47) were done when the first was not diagnostic. Cervical adenopathy was the presentation in 27 of 37 patients (73%), 6 of whom also had disseminated adenopathy. Upper aerodigestive tract (UAT) fiberoscopy had been negative in 16 and not performed in 7. The FNA specimens contained interpretable material in 42 of 47 cases (89%). Five FNA specimens were diagnostic of lymphoma (11%), but the type was classifiable in only one. Thus, 32 initial FNA specimens were not diagnostic, nor were 10 repeat FNA's on the same patients. Of the 32 patients who initially had non-diagnostic FNAs, a lymphoma diagnosis and classification was ultimately established by a single excisional lymph node biopsy. Lymphoma diagnosis was delayed in 19 patients because of FNA by 10–941 days; median 38, mean 68 days. Conclusions: Though 90% were not diagnostic, FNA was routinely, and sometimes repeatedly performed in patients with cervical adenopathy, most of whom had no evidence of UAT neoplasms, and some of whom had disseminated adenopathy. Significant delays in diagnosis were the result. Decisions concerning biopsy technique in patients with cervical adenopathy should be made in the context of clinical presentation.

No significant financial relationships to disclose.

Alkaline stress-induced apoptosis in human pulmonary artery endothelial cells

The effect of alkaline stress, or an increase in extracellular pH (pHext), on cell viability is poorly defined. Human pulmonary artery endothelial cells (HPAEC) were subjected to alkaline stress using different methods of increasing pHext. Viability and mode of cell death following alkaline stress were determined by assessing nuclear morphology, ultrastructural features, and caspase-3 activity. Incubation of monolayers in media set to different pHext values (7.4-8.4) for 24-h induced morphological changes suggesting apoptosis (35-45% apoptotic cells) following severe alkaline stress. The magnitude of apoptosis was related to the severity of alkaline stress. These findings were confirmed with an assessment of ultrastructural changes and caspase-3 activation. While there was no difference in the intracellular calcium level ([Ca(2+)](i)) in monolayers set to pHext 7.4 versus 8.4 following the first hour of alkaline stress, blockade of calcium uptake with the chelator, EGTA, potentiated the magnitude of apoptosis under these conditions. Potentiation of apoptosis was reduced by calcium supplementation of the media. Finally, alkaline stress was associated with an increase in intracellular pH. This is the first report of apoptosis following alkaline stress in endothelial cells in the absence of other cell death stimuli.

Enhancement of wound healing by shikonin analogue 93/637 in normal and impaired healing

Wound healing is a complicated biological process, which involves interactions of multiple cell types, various growth factors, their mediators and the extracellular matrix proteins. In this study, we evaluated the effects of shikonin analogue 93/637 (SA), derived from the plant Arnebia nobilis, on normal and hydrocortisone-induced impaired healing in full thickness cutaneous punch wounds in rats. SA (0.1%) was applied topically daily as an ointment in polyethylene glycol base on wounds. SA treatment significantly accelerated healing of wounds, as measured by wound contraction compared to controls in hydrocortisone-impaired animals. SA treatment promoted formation of granulation tissue including cell migration and neovascularization, collagenization and reepithelialization. The expression of basic fibroblast growth factor (bFGF) was higher as revealed by immunohistochemistry in treated wounds compared to controls. However, the expression of transforming growth factor-beta(1) was not affected by SA treatment. Since bFGF is known to accelerate wound healing, the increased expression of bFGF by SA may be partly responsible for the enhancement of wound healing. These studies suggest that SA could be further studied for clinical use to enhance wound healing.

Migratory pulmonary infiltrates in a patient with rheumatoid arthritis

The case history is described of an elderly man with rheumatoid arthritis receiving treatment with sulfasalazine and the cyclooxygenase-2 inhibitor celecoxib who presented with severe shortness of breath, cough, and decreased exercise tolerance. The chest radiograph showed unilateral alveolo-interstitial infiltrates and a biopsy specimen of the lung parenchyma showed changes consistent with acute eosinophilic pneumonia. Antibiotic treatment was unsuccessful, but treatment with steroids and discontinuation of sulfasalazine and celecoxib resulted in a marked clinical improvement confirmed by arterial blood gas analysis. The condition may have developed as an adverse reaction either to sulfasalazine or to celecoxib, although hypersensitivity to the latter has not previously been reported.

Is repeat prostate biopsy for high-grade prostatic intraepithelial neoplasia necessary after routine 12-core sampling?

OBJECTIVES

To determine whether repeat biopsy is necessary when the diagnosis of high-grade prostatic intraepithelial neoplasia (HGPIN) is made with a 12-core biopsy. Repeated biopsy has been recommended for individuals with HGPIN noted on sextant prostate biopsy because of the high likelihood of cancer detection. Recently, we have recommended the routine use of 12 cores, rather than 6, to improve cancer detection.

METHODS

The charts of all patients undergoing prostate biopsy during a 2-year period at the Manhattan Veterans Administration Medical Center were reviewed. Patients diagnosed with HGPIN on a 12-core biopsy were identified, and those undergoing a repeat 12-core biopsy within 1 year of the initial biopsy were evaluated to determine the rate of cancer detection.

RESULTS

A total of 619 men underwent biopsy during the study period. Of 103 men diagnosed with HGPIN, 43 underwent a repeat biopsy within 1 year at the discretion of the managing urologist. The mean age and median prostate-specific antigen level of those undergoing a repeat biopsy was 65.5 years and 5.37 ng/mL, respectively. At the time of the repeat biopsy, 1 patient was found to have cancer (2.3%), 20 had HGPIN (46.5%), 20 had benign pathologic findings (46.5%), and 1 patient (2.3%) had atypical small acinar proliferation.

CONCLUSIONS

A repeat biopsy after the diagnosis of HGPIN on 12-core prostate biopsy rarely results in cancer detection. In the absence of other factors increasing the suspicion of cancer, immediate repeat biopsy for HGPIN diagnosed on a 12-core biopsy is unnecessary.

Synchronous gastric adenocarcinomas in a patient with Meckel's diverticulum

Meckel's diverticulum, which is the most common congenital anomaly of the gastrointestinal tract, occurs when the vitelline duct persists past the 7th week of gestation. Although complications may occur in 8% to 22% of patients with Meckel's diverticula, adenocarcinoma is very uncommon. We describe a patient with early gastric cancer who was incidentally found to have a superficial adenocarcinoma arising from ectopic gastric mucosa within a Meckel's diverticulum. To the best of our knowledge, synchronous gastric adenocarcinoma in a patient with Meckel's diverticulum has not been previously reported.

Composite keratohyaline granules in striate keratoderma

The gross, light microscopic, and ultrastructural findings in a 55 year old man was striate keratoderma are presented. There was no family history of the disease. The lesions developed in his late teens and early adult years, and consisted of progressively worsening, raised, hyperkeratotic, linear plaques on the palm and volar surface of the third and fifth fingers bilaterally. There were also painful callosities on both heels, and thick, raised plaques on the heels and lateral plantar surfaces. The epidermis was papillomatous and acanthotic, with marked orthokeratosis, minimal parakeratosis, and a very thickened granular layer. No epidermolysis was seen. Electron microscopy showed increased tonofibrils in the stratum spinosum arranged in wavy, parallel bundles and a granular layer in which normal Odland bodies were present. However, the keratohyaline granules were large, with rounded borders and a striped, alternating, dark and light content characteristic of composite granules. There was diminished contact of the granules with tonofibrils. The transition to the stratum corneum was abrupt. The ultrastructural and genetic features of keratodermas, with special emphasis on the striate type, are reviewed.

Light microscopic and ultrastructural evidence of in vivo phagocytosis of Helicobacter pylori by neutrophils

Helicobacter pylori is believed to cause chronic active gastritis. Infection/colonization of the gastric mucosal surface induces a mucosal inflammatory reaction in the form of lymphocytic aggregates, plasma cells and, particularly, neutrophils, which may, in turn, damage the mucosal epithelium. In vitro studies demonstrate that, in culture, the bacilli are readily phagocytosed by neutrophils, this evoking a neutrophilic oxidative burst. However, it has been claimed that neutrophils do not phagocytose H. pylori in vivo. In this study of 19 endoscopic biopsies of gastric mucosa with H. pylori-associated gastritis, Cresyl violet staining for light microscopy and electron microscopy are used to demonstrate that, in vivo, neutrophils actively phagocytose and destroy the bacilli in the epithelial intercellular space and in the mucin on the surface of the mucosa. Direct contact of neutrophils with H. pylori was observed in 17 of 17 cases by light microscopy and in 4 of 15 cases by electron microscopy. Phagocytosis by neutrophils was seen in 14 of 17 cases by light microscopy and in 3 of 1 5 cases by electron microscopy. It was most evident in the surface mucus coat where "wolf packs" of neutrophils were seen attacking the microbes. Ultrastructurally, neutrophil phagolysosomes contained both intact and partially digested bacteria, convincing evidence that the primary function of neutrophils in chronic active gastritis is to destroy H. pylori organisms. This study leaves open the question of whether, or how, neutrophils damage the gastric mucosa.

A study of energy and effective atomic number dependence of the exposure build-up factors in biological samples

A theoretical method is presented to determine the gamma-radiation build-up factors in various biological materials. The gamma energy range is 0.015-15.0 MeV, with penetration depths up to 40 mean free paths considered. The dependence of the exposure build-up factor on incident photon energy and the effective atomic number (Zeff) has also been assessed. In a practical analysis of dose burden to gamma-irradiated biological materials, the sophistication of Monte Carlo computer techniques would be applied, with associated detailed modelling. However, a feature of the theoretical method presented is its ability to make the consequences of the physics of the scattering process in biological materials more transparent. In addition, it can be quickly employed to give a first-pass dose estimate prior to a more detailed computer study.

Role of vacuolar H(+)-ATPase in interferon-induced inhibition of viral glycoprotein transport

We have shown previously that interferon-beta (IFN-beta) induces the alkalinization of trans-Golgi network (TGN) and inhibits the transport of G protein of vesicular stomatitis virus (VSV) in L(B) cells and gD protein of herpes simplex virus (HSV-1) in LMtk- cells transfected with gD cDNA. The vacuolar H(+)-ATPase (V-ATPase) is responsible for maintaining pH in TGN, and V-ATPase-mediated acidification is required for normal transport of proteins. To examine whether alkalinization caused by IFN is mediated through V-ATPase, the activity of V-ATPase was determined in IFN-treated cells by coupling ATP hydrolysis to NADH oxidation. Bafilomycin (Baf) was used as positive control, as it specifically inhibits V-ATPase. The activity of V-ATPase was reduced in IFN-treated or Baf-treated cells compared with untreated cells. Doses of IFN-beta or Baf that neither alter pHi nor inhibit the transport of viral glycoproteins concomitantly inhibited the transport of G and gD proteins in TGN, as demonstrated by indirect immunofluorescence studies, and raised the pH of TGN as demonstrated by a decrease in the uptake of DAMP. Further, the effect of Baf on IFN-induced antiviral activity against VSV was examined to correlate the biologic significance of these findings. Data showed that Baf significantly enhances (5-50-fold) the IFN-induced antiviral activity as demonstrated by viral titers from supernatants. These findings suggest that the inhibition of transport of G and gD proteins by IFN-beta, may be related to the inhibition of V-ATPase-mediated acidification of TGN.

Arnebin-1 accelerates normal and hydrocortisone-induced impaired wound healing

Wound healing involves inflammation, cell proliferation, matrix deposition, and tissue remodeling. Interaction of different cells, extracellular matrix proteins, and their receptors are mediated by cytokines and growth factors during wound healing. In this study, we have evaluated the effect of arnebin-1, a natural product isolated from Arnebia nobilis, on normal and impaired wound healing in cutaneous punch wound model. Arnebin-1 was applied topically daily on wounds of hydrocortisone-treated or untreated animals. Arnebin-1 significantly accelerated healing of wounds with or without hydrocortisone treatment as revealed by a reduction in the wound width and gap length compared with controls. Arnebin-1 treatment promoted the cell proliferation, migration, and vessel formation to form a thick granulation tissue and re-epithelialization of the wounds. An increase in the synthesis of collagen, fibronectin and transforming growth factor-beta1 was seen in arnebin-1-treated wounds compared with the untreated control. As transforming growth factor-beta1 is known to enhance wound healing, and associated with the wound healing defect in hydrocortisone-treated wounds, the enhanced expression of transforming growth factor-beta1 at both translational and transcriptional level by arnebin-1 may be responsible for the enhancement of wound healing during normal and impaired wound repair. These studies suggest that arnebin-1 could be developed as a potent therapeutic agent for wound healing in steroid-impaired wounds.

Curcumin enhances wound healing in streptozotocin induced diabetic rats and genetically diabetic mice

Tissue repair and wound healing are complex processes that involve inflammation, granulation and tissue remodeling. Interactions of different cells, extracellular matrix proteins and their receptors are involved in wound healing, and are mediated by cytokines and growth factors. Previous studies from our laboratory have shown that curcumin (diferuloylmethane), a natural product obtained from the rhizomes of Curcuma longa, enhanced cutaneous wound healing in rats and guinea pigs. In this study, we have evaluated the efficacy of curcumin treatment by oral and topical applications on impaired wound healing in diabetic rats and genetically diabetic mice using a full thickness cutaneous punch wound model. Wounds of animals treated with curcumin showed earlier re-epithelialization, improved neovascularization, increased migration of various cells including dermal myofibroblasts, fibroblasts, and macrophages into the wound bed, and a higher collagen content. Immunohistochemical localization showed an increase in transforming growth factor-beta1 in curcumin-treated wounds compared to controls. Enhanced transforming growth factor-beta1 mRNA expression in treated wounds was confirmed by in situ hybridization, and laser scan cytometry. A delay in the apoptosis patterns was seen in diabetic wounds compared to curcumin treated wounds as shown by terminal deoxynucleotidyl transferase-mediated deoxyuridyl triphosphate nick end labeling analysis. Curcumin was effective both orally and topically. These results show that curcumin enhanced wound repair in diabetic impaired healing, and could be developed as a pharmacological agent in such clinical settings.

Thymosin beta4 accelerates wound healing

Angiogenesis is an essential step in the repair process that occurs after injury. In this study, we investigated whether the angiogenic thymic peptide thymosin beta4 (Tbeta4) enhanced wound healing in a rat full thickness wound model. Addition of Tbeta4 topically or intraperitoneally increased reepithelialization by 42% over saline controls at 4 d and by as much as 61% at 7 d post-wounding. Treated wounds also contracted at least 11% more than controls by day 7. Increased collagen deposition and angiogenesis were observed in the treated wounds. We also found that Tbeta4 stimulated keratinocyte migration in the Boyden chamber assay. After 4-5 h, migration was stimulated 2-3-fold over migration with medium alone when as little as 10 pg of Tbeta4 was added to the assay. These results suggest that Tbeta4 is a potent wound healing factor with multiple activities that may be useful in the clinic.

Acceleration of viral replication and up-regulation of cytokine levels by antimalarials: implications in malaria-endemic areas

Antimalarial drugs are widely used in malaria endemic areas, both for chemoprophylaxis and also empirically to treat patients presenting with fever. Previously, we have reported that chloroquine enhances the severity of Semliki forest virus (SFV) and encephalomyocarditis virus infection. The studies presented herein show that a broad spectrum of antimalarial drugs augmented the replication of SFV in mice, concomitant with greater tissue damage and up-regulation of mRNA levels of various inflammatory cytokine genes, including interleukin-1 receptor antagonist (IL-1Ra), II-1alpha, IL-1beta, IL-6, IL-12p40, and interferon-gamma inducing factor. Furthermore, chloroquine enhances IL-1Ra production in RAW cells in vitro. Since IL-1Ra is known to be up-regulated in a number of viral infections, we propose that a further enhancement of its expression by antimalarials may be responsible for the increased severity of viral infection in our studies. Thus, the widespread use of antimalarials in malaria-endemic areas may predispose the population to viral infections. Further studies are in progress to delineate mechanism(s) involved in cytokine up-regulation and acceleration of viral replication.

Picroliv -- a natural product protects cells and regulates the gene expression during hypoxia/reoxygenation

Cellular adaptation to hypoxia involves regulation of specific genes such as vascular endothelial growth factor (VEGF), erythropoietin (EPO) and hypoxia inducible factor (HIF)-1 . In this study, we have evaluated the protective effect of picroliv (a purified iridoid glycoside fraction from roots of Picrorhiza kurrooa with hepatoprotective, anti-inflammatory and antioxidant properties) against hypoxic injury by examining lactate dehydrogenase (LDH) release in Hep 3B and Glioma cells. The expression of hypoxia regulated genes, VEGF and HIF-1 was studied in human umbilical vein endothelial cells (HUVEC), Hep 3B and Glioma cells. Picroliv reduced the cellular damage caused by hypoxia as revealed by a significant reduction in LDH release compared to untreated control. The expression of VEGF and HIF-1 subunits (HIF-1alpha and HIF-1beta) was enhanced by treatment with picroliv during normoxia and hypoxia in HUVEC and Hep 3B cells and on reoxygenation the expression of these genes was significantly reduced as revealed by mRNA analysis using RT-PCR. Simultaneous treatment with picroliv during hypoxia inhibited VEGF and HIF-1 expression in Glioma cells whereas the expression was not reduced by picroliv treatment during reoxygenation as evidenced by both RT-PCR and Northern hybridization. VEGF expression as revealed by immunofluorescence studies correlates well with the regulations observed in the mRNA expression. We have also examined the kinase activity of tyrosine phosphorylated proteins and protein kinase C (PKC) in Glioma cells treated with picroliv during hypoxia/reoxygenation. A selective inhibition of protein tyrosine kinase activity leading to tyrosine dephosphorylation of several proteins including 80 kd protein, and a reduction in PKC was seen in cells treated with picroliv and hypoxia. These findings suggest that picroliv may act as a protective agent against hypoxia/reoxygenation induced injuries, and the underlying mechanism may involve a novel signal transduction pathway.

Inhibition of angiogenic differentiation of human umbilical vein endothelial cells by curcumin

Angiogenesis is a crucial step in the growth and metastasis of cancers. Curcumin inhibits tumor initiation and growth. We analyzed the effect of curcumin on endothelial cell migration, attachment, and tube formation on Matrigel. Curcumin had no effect on endothelial cell migration or attachment to either plastic or Matrigel. Curcumin treatment resulted in a dose-dependent inhibition of tube formation when the cells were treated before plating or at the time of plating on Matrigel. Curcumin treatment also caused the preformed tubes to break down. Curcumin inhibited angiogenesis in a s.c. Matrigel plug model in mice. The role of metalloproteinases has been shown to be important in angiogenesis; therefore, zymography was performed to determine whether curcumin affected protease activity. Zymographs of curcumin-treated culture supernatants showed a decrease in the gelatinolytic activities of secreted 53- and 72-kDa metalloproteinases. Western and Northern analysis showed a dose-dependent decrease in the protein expression and transcript of 72 kDa, indicating that curcumin may be exerting its inhibitory effect at both the transcriptional and posttranscriptional level. These findings suggest that curcumin acts as an angiogenesis inhibitor by modulating protease activity during endothelial morphogenesis. Curcumin could be developed as an antiangiogenic drug.

Enhancement of wound healing by curcumin in animals

Tissue repair and wound healing are complex processes that involve inflammation, granulation, and remodeling of the tissue. In this study, we evaluated the in vivo effects of curcumin (difeurloylmethane), a natural product obtained from the rhizomes of Curcuma longa on wound healing in rats and guinea pigs. We observed faster wound closure of punch wounds in curcumin-treated animals in comparison with untreated controls. Biopsies of the wound showed reepithelialization of the epidermis and increased migration of various cells including myofibroblasts, fibroblasts, and macrophages in the wound bed. Multiple areas within the dermis showed extensive neovascularization, and Masson's Trichrome staining showed greater collagen deposition in curcumin-treated wounds. Immunohistochemical localization of transforming growth factor-beta1 showed an increase in curcumin-treated wounds as compared with untreated wounds. In situ hybridization and polymerase chain reaction analysis also showed an increase in the mRNA transcripts of transforming growth factor-beta1 and fibronectin in curcumin-treated wounds. Because transforming growth factor-beta1 is known to enhance wound healing, it may be possible that transforming growth factor-beta1 plays an important role in the enhancement of wound healing by curcumin.

Thymosin alpha 1 stimulates endothelial cell migration, angiogenesis, and wound healing

In wound healing, lymphoid cells release soluble factors that attract fibroblasts and macrophages, initiating repair, endothelial cell migration, angiogenesis, and matrix production. We analyzed the effect of thymosin alpha1 (Talpha1) on endothelial cell migration, angiogenesis, and wound healing. Talpha1, a 28 amino acid peptide initially isolated from the thymus, enhanced the morphologic differentiation of endothelial cells and was a potent chemoattractant for endothelial cells and monocytes in vitro. In vivo, Talpha1 stimulated angiogenesis in a subcutaneous model. When given either topically or i.p., it accelerated wound healing in a punch model, demonstrating that Talpha1 promotes angiogenesis and wound healing.

Role of psychiatric disorders in self-inflicted periodontal injury: a case report

Self-inflicted or factitious injuries (FI) are not uncommon in psychiatric patients. In general, this kind of behavior is linked to secondary gain. However, the role of underlying psychiatric illness should not be overlooked. Usually, the diagnosis of factitious injury can be confirmed by a careful medical-dental history, clinical appearance of the lesion, laboratory investigations, and response to established treatment protocol. A case is presented in which repetitive injurious behavior resulted in rapid periodontal attachment loss. The lesion responded well to conservative periodontal treatment. The role of underlying psychiatric morbidity leading to repetitive self-injurious behavior is discussed.

Enhanced biosynthesis of extracellular matrix proteins and TGF-beta 1 by polyinosinic-polycytidylic acid during cutaneous wound healing in vivo

In our previous study, we have shown that polyinosinic-polycytidylic acid (poly I:C), a double-stranded RNA, and a potent inducer of interferon, enhanced the wound healing in rats and mice. Increased levels of laminin and collagen, and greater influx of dermal fibroblasts were observed in poly I:C-treated wounds as compared to untreated wounds (Bhartiya et al., 1992, J. Cell. Physiol., 150:312-319). In this study, we have explored the mechanism of enhanced wound healing by poly I:C in rats. Poly I:C (1 mg/kg) in phosphate buffered saline was injected intraperitoneally 18 h prior to wound healing, and the animals were sacrificed on day 3 postwounding. Immunofluorescence studies showed increased expression of adhesion molecules that includes ICAM-1 (intercellular adhesion molecule-1;CD54) and VCAM-1 (vascular cell adhesion molecule; CD 106) in poly I:C-treated wounds as compared to untreated control. Poly I:C treatment resulted in an increase in the mRNA levels of collagen type 1 (alpha), collagen III, laminin B1, and transforming growth factor-beta 1(TGF-beta 1) in wounds compared to untreated wounds as demonstrated by in situ hybridization and PCR analysis. These studies suggests that poly I:C upregulates the biosynthesis of adhesion molecules, extracellular matrix proteins (ECM), and TGF-beta 1 in the wound bed. Adhesion molecules and ECM play a major role in wound healing, and TGF-beta 1 has been known to be a potent wound healer. Therefore, the increased expression of these molecules may play a role in the enhanced healing by poly I:C observed in rats.

Curcumin inhibits the proliferation and cell cycle progression of human umbilical vein endothelial cell

We have studied the effect of curcumin (diferuloylmethane), a major component of the food flavor turmeric, on the proliferation and cell cycle progression of human umbilical vein endothelial cells (HUVEC). Curcumin inhibited the DNA synthesis of HUVEC as revealed by [3H]thymidine incorporation in a dose-dependent manner without significantly affecting the viability of the cells. The growth of HUVEC stimulated with fibroblast growth factor (FGF) and endothelial growth supplement (ECGS) was also inhibited by curcumin. Addition of curcumin to HUVEC resulted in an accumulation of > 46% of the cells in early S-phase, as determined by the FACS analysis. Pulse labeling studies with [3H]thymidine demonstrated that curcumin affected cells that were actively undergoing DNA synthesis. The de-novo synthesis of thymidine depends on thymidine kinase (TK) enzyme. Curcumin caused a significant loss of TK activity, which may be one of the possible mechanism(s) for the inhibition of DNA synthesis activity of HUVEC by curcumin. These studies have revealed a unique mode of action of curcumin whereby it effectively blocked the cell cycle progression during S-phase by inhibiting the activity of TK enzyme. The migration, proliferation and differentiation of HUVEC leads to angiogenesis, which facilitates the tumor initiation and promotion. Since curcumin inhibited the proliferation of HUVEC, it could turn out to be a very useful compound for the development of novel anti-cancer therapy.

Mechanism of enhancement of the antiviral action of interferon against herpes simplex virus-1 by chloroquine

Using double immunofluorescence, we have shown previously that interferon (IFN) treatment inhibits the transport of herpes simplex virus-1 (HSV-1) gD from the Golgi complex to the plasma membrane in the virus infected and gD cDNA transfected LMtk-cells. In the present study, we quantitated the gD protein on the cell surface and localized the gD protein in the trans-Golgi network (TGN). The results showed 10-fold less fluorescence for the gD protein on the cell surface in IFN-treated LMtk-cells. Subcellular fractionation studies demonstrated that gD was associated with TGN-enriched membranes. Gold labeling for DAMP distribution using electron microscopy showed that IFN raised the pH of TGN. IFNs induced alkalinization of TGN may be related to the block in the transport of HSV-1 gD. Earlier we reported that a subeffective dose of chloroquine (CHL) or IFN does not change the pHi. However, both CHL and IFN together raise the pHi significantly. To study the biologic significance of the finding, the effect of these subeffective doses of IFN and CHL on the antiviral activity and the transport of the gD protein was studied. Results suggested that CHL enhance the antiviral activity of IFN against HSV-1 and concomitantly increase the inhibition of HSV-1 gD transport. This IFN-induced increase in pHi of the TGN may also explain the inhibitory effect of IFN reported on the terminal steps of some of the enveloped viruses.

Brefeldin A inhibits the antiviral action of interferon against encephalomyocarditis virus

Brefeldin A (BFA), a unique fungal metabolite of a 13-membered lactone ring, exhibits various biological actions, including antitumor, antifungal and antiviral activities. In the present study, mouse LB cells were treated with various concentrations of interferon (IFN) and/or BFA overnight and infected with encephalomyocarditis virus (EMCV) after removal of IFN and BFA. Doses of BFA which neither inhibit the metabolism of the cell nor the infectivity of EMCV, decreased the IFN-induced antiviral activity against EMCV as demonstrated by virus titer from supernatants. Since 2-5A synthetase and double-stranded RNA (dsRNA)-dependent protein kinase (PKR) have been suggested to be involved in the antiviral action of IFN against EMCV, their activities were investigated in LB cells after BFA treatment. Northern blot analysis and in situ hybridization showed a decrease (2-3-fold) in the mRNA of 2'-5' oligoadenylate (2-5A) synthetase after BFA treatment. BFA also inhibited the activity of 2-5A synthetase, 2-5A dependent RNase and phosphorylation of PKR in cellular extracts, indicating that BFA may be exerting its inhibitory effect both at the transcriptional and post-transcriptional levels. This study reports a new biological action of BFA, demonstrating that BFA antagonized the antiviral action of IFN by inhibiting IFN-induced enzymatic pathways. These studies also suggest that both 2-5A and PKR are important in the antiviral activity of IFN against EMCV.

Defective transport of herpes simplex virus glycoprotein in interferon-treated cells: role of intracellular pH

We have investigated the mechanism(s) of interferon (IFN)-induced inhibition of assembly steps of herpes simplex virus (HSV-1) in mouse LB cells. Data showed that physiological doses of mouse IFN-beta (10-100 IU/ml) significantly inhibited the infectivity (5- to 100-fold) of HSV-1; however, viral protein synthesis was marginally inhibited (2- to 5-fold). Immunofluorescence studies showed that most of the HSV-1gD glycoprotein accumulated intracellularly in IFN-treated LB and LMtk- cells transfected with gD cDNA, as compared to untreated controls, where most of the gD was localized on the plasma membrane. Double-immunofluorescence studies demonstrated that rhodamine-labeled wheat germ agglutinin (WGA) was co-localized with gD protein, suggesting the block was in the transport from the trans-Golgi to the plasma membrane. IFN treatment of LB and LMtk- cells raised the intracellular pH as measured by DAMP distribution and SNARF-1 using laser spectroscopy; this could play an important role in the inhibition of transport of HSV-1gD.

Melanocyte halo explained

Electron microscopic examination was performed of skin biopsy specimens processed for electron microscopy directly after formaldehyde fixation, after retrieval from paraffin blocks, and as for paraffin embedding but with retrieval after clearing with xylene, the last step before paraffin infiltration. The halos surrounding melanocytes in the epidermis are a retraction artifact that develops during paraffin infiltration of the tissue. It is proposed that this artifact is related to the high temperature of the paraffin bath.

Metastatic meningioma. Hemangiopericytoma or angioblastic meningioma?

The question of whether meningeal hemangiopericytoma is a variant of meningioma ("angioblastic meningioma") or a nosologically distinct entity remains controversial. We present the case histories of an intracranial meningioma and of a meningeal hemangiopericytoma, both of which developed extracranial metastases. The metastatic lesions in both cases were studied by electron microscopy, which demonstrated pericytomatous differentiation in one instance and meningothelial differentiation in the other. This report supports the opinion that meningeal hemangiopericytomas and meningiomas of the CNS are distinct pathological entities.

Interferons upregulate the expression of laminin and its receptor LBP-32 in cultured cells

We have studied the effects of interferon (IFNs) alpha and gamma on the regulation and expression of laminin (LMN) and a 32 kD laminin binding protein (LPB-32) in cultured human umbilical vein endothelial cells (HUVEC) and human foreskin fibroblast (FS-4) cells. We show that IFNs increased immunofluorescent staining for LMN and LPB-32. In HUVEC, B1 and B2 chain immunoprecipitated proteins were enhanced in the extracellular (released) fraction by IFN-alpha, but were decreased by IFN-gamma. In intracellular (cell-associated) fractions, both B chains were increased, especially by IFN-gamma. In situ hybridization of FS-4 cells demonstrated increased B2 chain mRNA in the presence of IFNs. Reverse transcription-polymerase chain reaction amplification (RT-PCR) indicated that B1 chain mRNA was increased by both IFNs in HUVEC, and by IFN-gamma in FS-4. The increased synthesis of LMN and LBP-32 may be important in promoting wound healing and angiogenesis.

Loss of infectivity by progeny virus from alpha interferon-treated human immunodeficiency virus type 1-infected T cells is associated with defective assembly of envelope gp120

Levels of human immunodeficiency virus (HIV) DNA, RNA, or p24 antigen and reverse transcriptase activity in T-cell cultures treated with 500 IU of recombinant alpha interferon (rIFN alpha) per ml were comparable to those in control cultures. Radioimmunoprecipitation analysis of proteins in lysates of IFN-treated T cells documented a marked accumulation of HIV proteins. Localization of gp120 by immunofluorescence showed a diffuse pattern in IFN-treated cells quite distinct from the ring pattern in untreated control cells. That large quantities of gp120 in aberrant cell compartments might affect HIV morphogenesis was confirmed in infectivity studies: virions from IFN-treated cells were 100- to 1,000-fold less infectious than an equal number of virions from control cells. Direct examination of IFN-treated and control HIV-infected cells by transmission electron microscopy showed little difference in the number or distribution of viral particles. However, quantitation of gp120 by immunogold particle analysis revealed a marked depletion of envelope glycoprotein in virions released from IFN-treated cells. This defect in gp120 assembly onto mature viral particles provides a molecular basis for this loss of infectivity.

Relationship between structure and function of dietary fibre: a comparative study of the effects of three galactomannans on cholesterol metabolism in the rat

Male adult rats were fed on diets containing 80 g/kg galactomannans with different galactose (G): mannose (M) ratios/kg. The galactomannans were compared with purified cellulose (Solkaflok) and the animal were also fed on a basal diet free from fibre. All diets contained cholesterol (10 g/kg) and sodium cholate (2 g/kg). The three galactomannans were fenugreek gum (1G:1M), guar gum (1G:2M) and locust-bean gum (1G:4M). In comparison with the fibre-free and Solkaflok diets, all three galactomannans lowered the concentrations of cholesterol in both liver and blood plasma. The galactomannans also decreased the rate of hepatic synthesis of cholesterol. Dietary galactomannans increased caecal volatile fatty acids, particularly propionic, increased the weight of the caecum and its contents and increased the amount of water in the faeces. The increase in propionic acid production was significantly related to a decrease in caecal pH, but not to changes in plasma cholesterol or hepatic cholesterol synthesis. These effects were significantly influenced by chemical composition and structure of the galactomannan; they were most evident when the proportion of galactose in the galactomannan was highest (i.e. fenugreek gum). The three galactomannans also differed markedly in their effects on the viscosity of the digesta, but the galactomannan which gave the highest viscosity was least effective in lowering plasma cholesterol. A separate experiment with perfused loops of small intestine in vivo showed that the most effective galactomannan, fenugreek gum, had no direct effect on cholesterol absorption.

Diagnosis of Acanthamoeba infection by cutaneous manifestations in a man seropositive to HIV

A case of Acanthamoeba infection with cutaneous manifestations in a man seropositive for human immunodeficiency virus is reported. The diagnosis was made by identification of amoebic trophozoites and cysts in tissue specimens. Two other cases of disseminated Acanthamoeba infection with similar skin findings in patients with acquired immunodeficiency syndrome have been previously reported. Recognition of the cutaneous manifestations of acanthamoebiasis in patients seropositive for human immunodeficiency virus may lead to earlier diagnosis and improved therapy.

The platelet volume-number relationship in patients infected with the human immunodeficiency virus

The pathophysiology of thrombocytopenia in the acquired immune deficiency syndrome has not been elucidated completely. Many findings in these patients are identical to those with immune thrombocytopenic purpura. However, recent findings in acquired immune deficiency syndrome patients including the effect of zidovudine on platelet count and the demonstration of ultrastructural changes and viral RNA in megakaryocytes, have suggested that the human immunodeficiency virus may directly infect megakaryocytes, and play a role in acquired immune deficiency syndrome-related thrombocytopenia. To investigate further the mechanism of decreased platelet counts in human immunodeficiency virus-infected patients, the platelet volume-number relationship and corresponding bone marrow findings in 34 patients infected with human immunodeficiency virus were studied. Parameters evaluated included platelet count and mean platelet volume; bone marrow cellularity, megakaryocyte number, and number and percentage of denuded megakaryocyte nuclei. Two thirds of the platelet counts were low, and of these 92% had an inappropriately low mean platelet volume. These individuals had a platelet-volume number relationship that is very similar to that seen in myelosuppressive disorders. In addition, more than 90% of the bone marrows from thrombocytopenic patients had either normal or decreased numbers of megakaryocytes. These observations provide additional evidence to support the hypothesis that the pathophysiology of human immunodeficiency virus-associated thrombocytopenia may be due, at least in part, to a direct effect on the megakaryocytes.

Primary amines enhance the antiviral activity of interferon against a membrane virus: role of intracellular pH

Inhibition of vesicular stomatitis virus (VSV) replication in LB cells by interferon (IFN) resembles the action of IFN on some retroviruses, in that the incorporation of glycoprotein into virions is defective. Primary amines added between 1 and 2 h post-infection significantly enhanced (five- to 1000-fold) the antiviral activity of IFN against VSV, but no enhancement of the antiviral activity of IFN against encephalomyocarditis virus, a virus with no membrane component, by primary amines was seen. SDS-PAGE and immunofluorescence analysis of viral proteins, and Nycodenz gradient fractionation, suggested that both IFN and primary amines inhibited the transport of VSV glycoprotein (G) to the plasma membrane; instead, G accumulated in the trans-Golgi network (TGN). Using sensitive intracellular pH (pHi) indicators, we found that IFN treatment significantly raised the pHi. A further increase in pHi was seen with a combination of IFN and primary amines; the increase in pHi correlated with an enhancement of the antiviral activity of IFN by primary amines. Amiloride inhibited the IFN-induced increase in pHi and a concomitant increase in the concentration of Na+ ions; this observation suggested that IFN induced cytoplasmic alkalinization by activating an Na+/H+ antiporter system. These results indicated that the IFN-induced increase in pHi may be responsible for the accumulation of G in the TGN, thereby producing G-deficient virus particles with reduced infectivity.

High voltage redox properties of cytochrome c oxidase

In earlier studies evidence was obtained for the existence of both high and low redox potential forms of cytochrome a3 (Hendler et al. 1986. Biophys. J. 49:717-729; Hendler and Sidhu. 1988. Biophys. J. 54:121-133). The current paper describes additional experiments that support this conclusion and then reviews a large number of experimental observations that appear to be consistent with the view that cytochrome a3 displays at least (see Sidhu and Hendler. 1990. Biophys. J. 57:1125-1140) two different forms, which are distinguishable by their redox potentials, spectra, and reactivity with CO.

Mid-descending aortic traumatic aneurysms

Two patients with traumatic rupture of the mid-descending aorta successfully repaired are presented. Most clinical series of aortic tears do not include this entity. A review of the world literature reveals only 9 previous cases. In 6 of the 11 patients the diagnosis was either missed or delayed. In 4 patients the diagnosis was delayed or missed because of the absence of a superior mediastinal hematoma, and in 2 patients the diagnosis was delayed because of inadequate (single-plane) aortography. Suspicion may be lacking because of absence of the upper mediastinal hematoma considered to be the sine qua non for the diagnosis of aortic rupture. Although deceleration is considered to be the mechanism of injury in tears at the isthmus, severe hyperextension (often associated with fracture dislocation of the underlying thoracic vertebra) is considered to be the causative factor in descending aortic tears. Experience with the 2 patients presented here demonstrates that a high index of suspicion and complete two-plane aortography is required to avoid the potential for catastrophic outcome subsequent to overlooking a tear of the mid-descending aorta.