Natural fermentation of fresh Jasmine flowers inspired the development of a biotechnological ingredient with global anti-ageing properties.

OBJECTIVE: This study focused on the development of a new-to-world ingredient harnessing the natural potential of fresh Jasminum grandiflorum flowers to self-ferment by its phytobiome revealing flower content. Analytical investigations were conducted to highlight specific phytocompounds generated during the natural fermentation of flowers in comparison to a conventional extraction. The synergy with another extraction technology maximized the generation of biocompounds for an interesting efficacy. METHODS: Jasmine extract was elaborated by combining two patented technologies: the phytofermentology™, inspired by plant-microorganisms interaction and designed to develop ingredients obtained by natural fermentation of the vegetal using its own phytobiota; and the PSR™ technology allowing the extraction of bioactive phytocompounds such as small RNAs from plants. RESULTS: Analytical investigations of Jasmine extract highlighted uniqueness and richness of the phytocompound profiles, such as organics acids and phenolic compounds, markers of fermentation only obtained after phytofermentology in comparison to conventional extraction. Jasmine extract has the particularity to contain jasmintides, flower small peptides belonging to the family of cysteine-rich peptides (CRPs). Antioxidant and global anti-ageing properties were investigated in cell-free assays demonstrating interesting results: about 20% scavenging of free radicals from 0.5% of Jasmine extract and protection from DNA damage of 26% in comparison to a stressed control. CONCLUSION: Phytofermentology™ technology combined with PSR™ technology, meant to be respectful of the environment, allowed to development of biofunctionals very close to nature with a unique analytical signature as Jasmine extract, using the potential of fresh flowers phytobiota to self-ferment. The efficacy of the ingredient on global antioxidation and anti-ageing via hyaluronidase/tyrosinase inhibitions was highlighted by cell-free evaluation assays. Further and complementary studies should be conducted to confirm the bioefficacy of this ingredient with in vitro / ex vivo assays.

Cette étude a pour objectif de développer un nouvel ingrédient unique en exploitant le potentiel des fleurs fraîches de Jasminum grandiflorum à fermenter naturellement en utilisant leur phytobiome, révélant ainsi le contenu de ces fleurs. Des investigations analytiques ont été menées pour mettre en évidence des phytocomposés spécifiques générés lors de la fermentation naturelle des fleurs par rapport à une extraction conventionnelle. La synergie avec une autre technologie d'extraction maximise la génération de biocomposés pour une plus grande efficacité de l'extrait. L'extrait de jasmin a été élaboré en combinant deux technologies brevetées: la phytofermentologie™, inspirée de l'interaction plante/micro­organismes et conçue pour développer des ingrédients obtenus par fermentation naturelle d'un végétal en utilisant son propre phytobiote; et la technologie PSR™ permettant l'extraction de phytocomposés bioactifs tels que les petits ARN des plantes. Les recherches analytiques de l'extrait de jasmin ont mis en évidence le caractère unique et la richesse des profils des différents phytocomposés composant l'extrait, tels que les acides organiques et les composés phénoliques, marqueurs de fermentation obtenus uniquement grâce à la phytofermentologie par rapport à l'extraction conventionnelle. L'extrait de jasmin a la particularité de contenir des jasmintides, petits peptides de fleurs appartenant à la famille des peptides riches en cystéine (CRP). Les propriétés antioxydantes et anti­âge ont été étudiées par des tests acellulaires démontrant des résultats intéressants: environ 20 % d'élimination des radicaux libres à partir de 0,5 % d'extrait de jasmin et une protection contre les dommages à l'ADN de 26 % par rapport à un contrôle stressé. La technologie phytofermentologie™ combinée à la technologie PSR™, se voulant respectueuse de l'environnement, a permis de développer des ingrédients très proches de la nature avec une signature analytique unique comme l'extrait de Jasmin, utilisant le potentiel d'auto­fermentation du phytobiote des fleurs fraîches. L'efficacité de l'ingrédient sur l'antioxydation globale et l'anti­âge via les inhibitions enzymatiques de la hyaluronidase et de la tyrosinase a été mise en évidence par des tests d'évaluation acellulaires. Des études supplémentaires et complémentaires devraient être menées pour confirmer la bioefficacité de cet ingrédient avec des tests in vitro/ex vivo.

Microarray profiling of gene expression in human keratinocytes suggests a new protective activity against UV-induced DNA damage for a compound previously known to interact with SCF-KIT signalling pathway.

The stem cell factor (SCF) and its protein-tyrosine kinase receptor KIT are together implicated in the regulation of diverse biological processes and particularly in melanogenesis. Indeed, this signalling pathway controls melanoblast migration from the neural crest during embryogenesis and allows the communication between keratinocytes and melanocytes in the adult. In melanocytes, the binding of SCF to its transmembrane receptor leads to the activation of signalling pathways implicating protein kinases which finally control the expression of pigmentation-related genes. We have developed a biological compound called IV09.007, which we previously described as a modulator of the SCF/KIT signalling pathway with a pro-pigmenting effect. In the present work, we have studied the expression and localization of both SCF and KIT mRNAs and proteins in the skin or skin-derived cell lines. Then, we explored with a microarray approach the ability of IV09.007 to modulate the expression of genes in human keratinocytes and melanocytes in culture. Thereby, we observed the regulation of genes implicated in DNA repair, mainly related to base/nucleotides excision pathways. A modulated transcriptional response was also observed for some genes implicated in the response against oxidative stress, in apoptosis inhibition and in lowering inflammatory immune response. These microarray results predicted a conferred protective effect of IV09.007 and we verified this hypothesis by performing comet assays on UVB-irradiated keratinocytes or melanocytes, to demonstrate the efficacy of IV09.007 on preventing DNA damage.

Mandible changes evaluated by computed tomography following Botulinum Toxin A injections in square-faced patients.

BACKGROUND: A facial contour that is oval is more pleasing in Asian women. Patients with a square face often seek facial contouring procedures to improve their appearance. Treatment often involves various combinations of Botulinum NeuroToxin A (BoNTA) injections into the masseters and/or mandibular angle resection. Many physicians claim that muscle paralysis with injections alone will decrease pulling on the underlying bone and also treat underlying bony flaring when present. Muscular changes after BoNTA injections have been well documented. However, the effect of BoNTA injections on the underlying mandibular bone morphology has not been studied to the best of the authors' knowledge. The goal of this study was to determine whether there are mandibular changes after masseter injection with botulinum toxin. METHODS: In this retrospective study of ten female patients seeking treatment for a square face, three-dimensional CT scans were taken before and 3 months after standardized BoNTA injections in bilateral masseters. Mandibular cortex thickness, mandibular bone thickness, and mandibular volume were measured. RESULTS: Soft-tissue changes were observed but no bony changes were observed 3 months after injections. CONCLUSIONS: In this study of adult patients, there were no statistically significant mandibular changes 3 months after BoNTA injection. The current theory of mandibular flaring resolution after partial muscle paralysis is not supported by our findings. Therefore, a patient presenting both masseteric hypertrophy and bony flaring will most likely require a combined muscular and bony procedure.

Alveolar bone grafting in the treatment of midline alveolar cleft and diastema in incomplete median cleft lip.

Median cleft lip is a rare congenital anomaly. The wide diastema with mesial tipping observed in these patients has been largely overlooked. A midline submucosal alveolar cleft prevents adequate treatment. The purpose of this article is to describe an alveolar bone grafting (ABG) technique used in the combined surgical-orthodontic approach to diastema treatment in patients presenting with incomplete median cleft lip. Patients treated for incomplete median cleft lip and diastema were identified in the clinic registry from 1981 to 2007. Six patients were identified; 4 underwent ABG before permanent maxillary incisor eruption, the other 2 were seen later when they were 11 years old. All 6 ABGs were successful. The incisors erupted through the graft or were successfully moved into it with lasting results. Follow-up ranged from 8 to 21 years. The existence of a midline submucosal alveolar cleft and subsequent diastema should be recognized and addressed in all patients who present with incomplete median cleft lip repair. This includes taking maxillary occlusal view X-rays before the age of 5 years to detect the cleft, and proceed to ABG if necessary, generally before permanent maxillary incisor eruption.

Caspase-2 deficiency prevents programmed germ cell death resulting from cytokine insufficiency but not meiotic defects caused by loss of ataxia telangiectasia-mutated (Atm) gene function.

It is well established that programmed cell death claims up to two-thirds of the oocytes produced during gametogenesis in the developing fetal ovaries. However, the mechanisms underlying prenatal germ cell loss in females remain poorly understood. Herein we report that caspase-11 null female mice are born with a reduced number of oocyte-containing primordial follicles. This phenotype is likely due to failed cytokine processing known to occur in caspase-11 mutants since neonatal female mice lacking both interleukin (IL)-1alpha and IL-1beta also exhibit a reduced endowment of primordial follicles. In addition, germ cell death in wild-type fetal ovaries cultured ex vivo is suppressed by either cytokine, likely via ligand activation of type 1 IL-1 receptors expressed in fetal germ cells. Normal oocyte endowment can be restored in caspase-11 null female mice by simultaneous inactivation of the gene encoding the cell death executioner enzyme, caspase-2. However, caspase-2 deficiency cannot overcome gametogenic failure resulting from meiotic recombination defects in ataxia telangiectasia-mutated (Atm) null female mice. Thus, genetically distinct mechanisms exist for developmental deletion of oocytes via programmed cell death, one of which probably functions as a meiotic quality-control checkpoint that cannot be overridden.

Intrathecal fentanyl does not modify the duration of spinal procaine block.

PURPOSE: To document the clinical characteristics of spinal procaine with or without the addition of fentanyl in light of the failure rate observed previously with procaine 10%. METHODS: In a randomized, prospective, double-blind study, 52 patients received spinal anesthesia with 100 mg procaine and either saline 0.9% (0.4 ml) (CONTROL group) or 20 microg fentanyl (0.4 ml) (FENTANYL group). Sensory anesthesia to needle prick was evaluated each minute for ten minutes, every three minutes for 33 minutes and every five minutes until regression to T10. Motor block was assessed with the Bromage scale. Patients were questioned by telephone for pain suggesting transient radicular irritation (TRI) 48 hr later. RESULTS: Mean time to reach highest sensory level, maximum number of segments blocked and mean time for regression of the sensory level to T10 showed no difference. Time to recuperate to full flexion of knees and feet (Bromage 4) showed no difference. Nine patients had nausea (five in CONTROL group and four in FENTANYL group) and nine had pruritus (three in CONTROL group and six in FENTANYL group). No patient reported pain suggesting TRI. CONCLUSION: Spinal procaine is appropriate for short-duration surgery. Fentanyl does not change the characteristics of the block or the incidence of side effects associated with spinal procaine.

Spinal anesthesia: a comparison of procaine and lidocaine.

PURPOSE: To compare spinal procaine to spinal lidocaine with regard to their main clinical characteristics and incidence of transient radicular irritation (TRI). METHODS: In this randomized, double-blind, prospective study, patients (two groups, n=30 each) received either 100 mg of lidocaine 5% in 7.5% glucose (Group L) or 100 mg of procaine 10% diluted with 1 ml cerebrospinal fluid (Group P). After spinal anesthesia, segmental level of sensory block was assessed by pinprick. Blood pressure and the height of the block were noted each minute for the first ten minutes, then every three minutes for the next 35 min and finally every five minutes until regression of the block to L4. Motor blockade was evaluated using the Bromage scale. To evaluate the presence of TRI, each patient was questioned 48 hr after surgery. RESULTS: Time to highest sensory level and to maximum number of segments blocked showed no difference between groups. Mean time for sensory regression to T10 and for regression of the motor block were shorter in Group P. Eighty minutes following injection, sensory levels were lower in Group P. Five patients had inadequate surgical anesthesia in Group P and only one in Group L. No patient in Group P had TRI (95% CI 10-12%) while eight (27%) in Group L did (95% CI 12-46%). CONCLUSIONS: Procaine 10% was associated with a clinical failure rate of 14.2%. This characteristic must be balanced against an absence of TRI, which occurs more frequently with the use of lidocaine 5%.

Spinal procaine with and without epinephrine and its relation to transient radicular irritation.

PURPOSE: To document the clinical characteristics of procaine with or without the addition of epinephrine. METHODS: In this randomized, prospective, double blind study, 62 patients received spinal anesthesia with 100 mg procaine and either 0.3 mg epinephrine (EPI group) or 0.3 ml NaCl 0.9% (SALINE group). Sensory anesthesia to needle prick was evaluated q 1 min for 10 min, q 3 min for 33 min and q 5 min until regression to L4. Motor block was assessed with the Bromage scale. Patients were questioned, by telephone, for transient radicular irritation (TRI) 48 hr later. RESULTS: Time to reach highest sensory level and number of segments blocked showed no difference. Mean time for regression of the sensory level to T10 was longer in EPI (83 +/- 23 vs 66 +/- 20 min, P < 0.01). Time to recuperate to full flexion of knees and feet (Bromage 4) was longer in EPI (126 +/- 37 vs 100 +/- 30 min, P < 0.01). Patients in EPI received more ephedrine. Eighteen patients had nausea (15 EPI/3 SALINE, P < 0.0015). One patient had TRI, incidence: 1.67%, 95% CI (< 1%-9%). CONCLUSION: Spinal procaine is appropriate for surgery of short duration. Epinephrine prolongs sensory and motor blocks by 25%. However, it is associated with a high incidence of nausea.

Defects in regulation of apoptosis in caspase-2-deficient mice.

During embryonic development, a large number of cells die naturally to shape the new organism. Members of the caspase family of proteases are essential intracellular death effectors. Herein, we generated caspase-2-deficient mice to evaluate the requirement for this enzyme in various paradigms of apoptosis. Excess numbers of germ cells were endowed in ovaries of mutant mice and the oocytes were found to be resistant to cell death following exposure to chemotherapeutic drugs. Apoptosis mediated by granzyme B and perforin was defective in caspase-2-deficient B lymphoblasts. In contrast, cell death of motor neurons during development was accelerated in caspase-2-deficient mice. In addition, caspase-2-deficient sympathetic neurons underwent apoptosis more effectively than wild-type neurons when deprived of NGF. Thus, caspase-2 acts both as a positive and negative cell death effector, depending upon cell lineage and stage of development.

Activation of caspase-2 in apoptosis.

Members of the CED-3/interleukin-1beta-converting enzyme (ICE) protease (caspase) family are synthesized as proforms, which are proteolytically cleaved and activated during apoptosis. We report here that caspase-2 (ICH-1/NEDD-2), a member of the ICE family, is activated during apoptosis by another ICE member, a caspase-3 (CPP32)-like protease(s). When cells are induced to undergo apoptosis, endogenous caspase-2 is first cleaved into three fragments of 32-33 kDa and 14 kDa, which are then further processed into 18- and 12-kDa active subunits. Up to 50 microM N-acetyl-Asp-Glu-Val-Asp-aldehyde (DEVD-CHO), a caspase-3-preferred peptide inhibitor, inhibits caspase-2 activation and DNA fragmentation in vivo, but does not prevent loss of mitochondrial function, while higher concentrations of DEVD-CHO (>50 microM) inhibit both. In comparison, although the activity of caspase-3 is very sensitive to the inhibition of DEVD-CHO (<50 nM), inhibition of caspase-3 activation as marked by processing of the proform requires more than 100 microM DEVD-CHO. Our results suggest that the first cleavage of caspase-2 is accomplished by a caspase-3-like activity, and other ICE-like proteases less sensitive to DEVD-CHO may be responsible for activation of caspase-3 and loss of mitochondrial function.

Characterization of the avian Ich-1 cDNA and expression of Ich-1L mRNA in the hen ovary.

We have sequenced the chicken interleukin-1beta-converting enzyme (ICE) and ced-3 homolog (Ich-1) cDNA, and evaluated Ich-1 mRNA expression in the hen ovary during follicle development. While two alternatively spliced forms of Ich-1, Ich-1L and Ich-1S, were amplified by PCR from an embryonic chicken cDNA library, only the Ich-1L form was found to be expressed in adult ovarian granulosa and theca tissues. The deduced amino acid (aa) sequence of ICH-1L is 70.8% identical to human ICH-1L and contains the conserved QACRG peptide active catalytic sequence characteristic of many ICE-related family of cysteine proteases.

Specific cleavage of alpha-fodrin during Fas- and tumor necrosis factor-induced apoptosis is mediated by an interleukin-1beta-converting enzyme/Ced-3 protease distinct from the poly(ADP-ribose) polymerase protease.

Interleukin-1beta-converting enzyme (ICE)/Ced-3 proteases play a critical role in apoptosis. One well characterized substrate of these proteases is the DNA repair enzyme poly(ADP-ribose) polymerase. We report here that alpha-fodrin, an abundant membrane-associated cytoskeletal protein, is cleaved rapidly and specifically during Fas- and tumor necrosis factor-induced apoptosis; this cleavage is mediated by an ICE/Ced-3 protease distinct from the poly(ADP-ribose) polymerase protease. Studies in cells treated with these apoptotic stimuli reveal that both fodrin and poly(ADP-ribose) polymerase proteolysis are inhibited by acetyl-Tyr-Val-Ala-Asp chloromethyl ketone and CrmA, specific inhibitors of ICE/Ced-3 proteases. However, fodrin proteolysis can be distinguished from poly(ADP-ribose) polymerase proteolysis by its relative insensitivity to acetyl-Asp-Glu-Val-Asp aldehyde (DEVD-CHO), a selective inhibitor of a subset of ICE/Ced-3 proteases that includes CPP32. DEVD-CHO protects cells from Fas-induced apoptosis but does not prevent fodrin proteolysis, indicating that cleavage of this protein can be uncoupled from apoptotic cell death. Moreover, purified fodrin is cleaved in vitro by CPP32 (but not by ICE) into fragments of the same size observed in vivo during apoptosis. These findings suggest that fodrin proteolysis in vivo may reflect the activity of multiple ICE/Ced-3 proteases whose partial sensitivity to DEVD-CHO reflects a limited contribution from CPP32, or an ICE/Ced-3 protease less sensitive than CPP32 to DEVD-CHO inhibition.

Activation of an interleukin 1 converting enzyme-dependent apoptosis pathway by granzyme B.

Cytotoxic T lymphocytes (CTL) can induce apoptosis through a granzyme B-based killing mechanism. Here we show that in cells undergoing apoptosis by granzyme B, both p45 pro-interleukin 1 beta converting enzyme (ICE) and pro-CPP32 are processed. Using ICE deficient (ICE -/-) mice, embryonic fibroblasts exhibit high levels of resistance to apoptosis by granzyme B or granzyme 3, while B lymphoblasts are granzyme B-resistant, thus identifying an ICE-dependent apoptotic pathway that is activated by CTL granzymes. In contrast, an alternative ICE-independent pathway must also be activated as ICE -/- thymocytes remain susceptible to apoptosis by both granzymes. In ICE -/- B cells or HeLa cells transfected with mutant inactive ICE or Ich-1S that exhibit resistance to granzyme B, CPP32 is processed to p17 and poly(ADP-ribose) polymerase is cleaved indicating that this protease although activated was not associated with an apoptotic nuclear phenotype. Using the peptide inhibitor Ac-DEVD-CHO, apoptosis as well as p45 ICE hydrolysis are suppressed in HeLa cells, suggesting that a CPP32-like protease is upstream of ICE. In contrast, p34cdc2 kinase, which is required for granzyme B-induced apoptosis, remains inactive in ICE -/- B cells indicating it is downstream of ICE. We conclude that granzyme B activates an ICE-dependent cell death pathway in some cell types and requires a CPP32-like Ac-DEVD-CHO inhibitable protease acting upstream to initiate apoptosis.

Effects of human immunodeficiency virus type 1 infection on programmed cell death in the presence or absence of Bcl-2.

The effect of human immunodeficiency virus (HIV-1) infection on the programmed cell death of CD4+ lymphocytes was studied by using Jurkat cells stably expressing high levels of the Bcl-2 protein (Jurkat-Bcl2) or control cells (Jurkat-P). Both Jurkat-Bcl2 and Jurkat-P cells exhibited surface CD4 expression adequate to support HIV-1 infection. We observed no differences between HIV-1-infected Jurkat Bcl2 cells and control cells with respect to kinetics of virus replication, protein expression, and processing. Severe cytopathic effects, which were typical of acute HIV-1 infection and consisted of syncytium formation followed by single-cell lysis, were observed in both cell types. However, several lines of evidence, such as cell viability analysis by trypan blue dye exclusion, chromosomal DNA laddering, and morphologic analysis by acridine orange/ethidium bromide or Giemsa staining, indicated that HIV-1 did not induce a significant amount of programmed cell death in either cell type. These results suggest that apoptosis is at most a minor element in HIV-1-induced cytopathicity in Jurkat lymphocytes.

Ich-1, an Ice/ced-3-related gene, encodes both positive and negative regulators of programmed cell death.

We report here the isolation and characterization of Ich-1, a gene related to the C. elegans cell death gene ced-3 and the mammalian homolog of ced-3, interleukin-1 beta-converting enzyme (ICE). Alternative splicing results in two distinct Ich-1 mRNA species. One mRNA species encodes a protein product of 435 amino acids (ICH-1L) that is homologous to both the P20 and P10 subunits of ICE (27% identity) and the entire CED-3 protein (28% identity). The other mRNA encodes a 312 amino acid truncated version of ICH-1L protein (ICH-1S). Overexpression of IchL induces programmed cell death, suggesting that Ich-1 is also a mammalian programmed cell death gene. More interestingly, overexpression of the Ich-1S suppresses Rat-1 cell death induced by serum deprivation. These observations suggest that Ich-1 plays an important role in both positive and negative regulation of programmed cell death in vertebrate animals.

Possible red-man syndrome associated with systemic absorption of oral vancomycin in a child with normal renal function.

OBJECTIVE: To report possible red-man syndrome (RMS) associated with oral administration of vancomycin. CASE SUMMARY: A 23-month-old child with acute myeloblastic leukemia developed symptoms compatible with RMS while receiving oral vancomycin for suspected Clostridium difficile colitis. Serum concentrations of vancomycin, measured at the time of the clinical episode, demonstrated significant oral absorption of the drug. Serum concentrations of vancomycin decreased later, implying a possible decrease in absorption, after the patient's neutrophil count returned to normal. The child later experienced another clinical episode compatible with RMS while vancomycin was being administered intravenously for suspected sepsis. DISCUSSION: There is no published report of RMS following oral administration of vancomycin. The reaction described took place while the child was neutropenic. Because of the absence of any significant renal function alteration that could explain the importance of the serum concentrations observed, we assume that C. difficile, neutropenia-, and chemotherapy-associated colitis may have resulted in extensive intestinal lesions, leading to an increased amount of vancomycin being systemically absorbed. This increased absorption during profound neutropenia may have been sufficient to exceed a purported threshold, leading to RMS. CONCLUSIONS: This case demonstrates that significant absorption of vancomycin may occur in neutropenic patients with normal renal function, and that it may be accompanied by RMS, usually associated with rapid infusions or large parenteral doses of the drug.

Target cell-specific determinants of membrane fusion within the human immunodeficiency virus type 1 gp120 third variable region and gp41 amino terminus.

The entry of human immunodeficiency virus type 1 (HIV-1) into target cells involves binding to the viral receptor (CD4) and membrane fusion events, the latter influenced by target cell factors other than CD4. The third variable (V3) region of the HIV-1 gp120 exterior envelope glycoprotein and the amino terminus of the HIV-1 gp41 transmembrane envelope glycoprotein have been shown to be important for the membrane fusion process. Here we demonstrate that some HIV-1 envelope glycoproteins containing an altered V3 region or gp41 amino terminus exhibit qualitatively different abilities to mediate syncytium formation and virus entry when different target cells are used. These results demonstrate that the structure of these HIV-1 envelope glycoprotein regions determines the efficiency of membrane fusion in a target cell-specific manner and support a model in which the gp41 amino terminus interacts directly or indirectly with the target cell during virus entry.

Attenuation of human immunodeficiency virus type 1 cytopathic effect by a mutation affecting the transmembrane envelope glycoprotein.

The cytopathic effects of human immunodeficiency virus type 1 (HIV-1) infection are specific for cells that express the CD4 viral receptor and consist of syncytium formation and single-cell lysis. Here we report that a mutation (517A) affecting the amino terminus of the HIV-1 gp41 transmembrane envelope glycoprotein resulted in a virus that was markedly less cytopathic than was wild-type HIV-1. In systems in which cell-to-cell transmission of HIV-1 occurred, the replication ability of the 517A virus was comparable with that of the wild-type virus. Even though the levels of viral protein expression, virion production, and interaction of the envelope glycoproteins with CD4 were similar for the 517A and wild-type viruses, both syncytium formation and single-cell lysis were attenuated for the 517A mutant virus. These results demonstrate that an envelope glycoprotein region important for mediating post-receptor binding events in cell membrane fusion is important for the induction of cytopathic effects by HIV-1. These results also indicate that levels of HIV-1 viral proteins or viral particles produced in infected cells are in themselves not sufficient to induce cytopathic effects.