Cytotoxicity, Antimicrobial, Anti-inflammatory and Antioxidant Activity of Camellia Sinensis and Citrus Mediated Copper Oxide Nanoparticle-An In vitro Study

Aim

Several applications of copper oxide nanoparticles (CuONPs) have been documented in various fields, including healthcare, dentistry, medication delivery, tissue and cancer imaging, biolabeling, and biosensing. Therefore, this study aimed to synthesize CuONPs using the plant extracts of Camellia Sinesis (CS) and citrus limon (CL). The nanoparticles were then evaluated for their cytotoxicity, antibacterial, anti-inflammatory, and antioxidant activities.

Materials and Methods

CuONPs were prepared using CS and CL through the green synthesis method. The Zone of Inhibition (ZOI) test was used to assess the antibacterial activity against strains of Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, and Candida albicans. The albumin denaturation assay was used to assess the substances' anti-inflammatory activity. The cytotoxicity was determined by conducting the brine shrimp lethality test. Additionally, the antioxidant nature was tested using the 1,1-diphenyl-2-picryl hydrazyl method.

Results

CuONPs mediated by CS and CL were successfully synthesized. The nanoparticles demonstrated significant antimicrobial activity against the bacteria being studied, specifically S. aureus. The cytotoxic effect was observed to be the least when the concentrations were below 20 µL. A potent antioxidant effect, characterized by its maximum absorbance at 517 nm, was observed at a concentration of 50 µL. A significant anti-inflammatory effect was noted for all tested concentrations.

Conclusion

The use of CS- and CL-mediated CuONPs demonstrates a favorable antimicrobial effect with reduced cytotoxicity, as well as improved anti-inflammatory and antioxidant effects at higher concentrations.

Association of crossbite with vertical skeletal growth patterns: A retrospective study

Crossbite is a type of malocclusion in which teeth are positioned more buccally or lingually than their corresponding opposing tooth in the upper or lower dental arch, resulting in a lateral mismatch of the teeth in the dental arches. Crossbite can be unilateral or bilateral, and it can be anterior or posterior. The link between crossbite and skeletal growth pattern remains uncertain. The current study aimed to find the prevalence of crossbite in subjects visiting a private dental hospital and evaluate if there is any association between crossbite and skeletal growth pattern. Data required for the study were procured from the dental information archiving software. The data were sorted and entered into an Excel spreadsheet. IBM SPSS software version 23 was used to conduct the statistical analysis. Graphs and tables were used to interpret the findings. the prevalence of crossbite was found to be 6.4%. Subjects with horizontal growth pattern commonly had crossbite, but no statistical significance (P = 0.07), standard deviation (1.011), was noted. There was no statistically significant association between different skeletal growth patterns however subjects with horizontal growth pattern reported more commonly with crossbite.

Association of vertical growth pattern with canine impactions in Dravidian subjects

Canine impaction, ectopic canines, canine transposition, canine transmigration, and agenesis are all caused by disturbances during development and eruption of the teeth. The position of the canines is of utmost importance, and they should be carefully inspected as they follow the longest path during eruption in the oral cavity and their shape and position play a major role in occlusal guidance. The prevalence of canine impaction may also be connected to the pattern of facial growth. The objective of this study was to analyze the association of vertical growth pattern and canine impaction in Dravidian population. The dental records were consulted for information. The patient information was gathered from the outpatient data records of patients who were treated with fixed orthodontic treatment at the private dental setup. Patients with canine impactions were shortlisted. Malocclusion, growth pattern, and type of impaction were recorded. The data obtained were tabulated and analyzed using statistical software. Out of 1385 subjects, 35 patients had impacted canines. Among 35 patients with impacted canines, 23 (65.71%) have a vertical growth pattern, 6 (17.14%) have an average growth pattern, and 6 (17.14%) have a horizontal growth pattern. According to the findings of this investigation, there was no gender-related difference in canine impaction. The canine impaction prevalence in Dravidian subjects was found to be 2.53%. Most of them with impacted canines had a vertical growth pattern.

Synthesis, characterization, and antimicrobial activity of silver nanoparticles derived from Mentha X piperita + Ocimum tenuiflorum: An in vitro study

The objective of the study was to synthesize silver nanoparticles using Mentha X Piperita (Mint) + Ocimum tenuiflorum (tulsi) and to confirm its size and shape. 0.5 mg of tulsi and 0.5 mg mint were diluted in distilled water (100 ml). The dissolved formulation was heated for 15 min at 70°C and filtered. The filtrate was homogeneously combined with 0.9 mg of silver nitrate to prepare nanoparticles of silver (AgNPs). The characterization of the obtained nanoparticle was done using transmission electron microscopy. Using agar disc diffusion assay, the antibacterial property was evaluated against common oral microbes at different concentrations. Silver nanoparticles showed excellent antimicrobial activity against Streptococcus mutans at 100 μL concentration. At 25 and 50 μL, all microbes showed similar extent of antimicrobial activity when quantified. Tulsi and mint prove to be effective in synthesizing silver nanoparticles that have good antimicrobial activity against oral microbes.

Assessment of anterior open bite prevalence in children visiting a dental hospital - A retrospective evaluation

Anterior open bite (AOB) is the insufficient vertical overlapping between the maxillary and mandibular anteriors when the teeth are in centric occlusion. The purpose of this study was to determine the prevalence of AOB in children and adolescents who visited a private dental hospital. In this study, subjects aged between 16 and 18 years with AOB were included. Data about orthodontic examination of patients were taken from preentered dental records of the hospital. Data of patients with AOB regarding age, gender, and intraoral and extraoral features were collected from the case records of the subjects, and statistical analysis was performed (Chi-square test and nonparametric correlations). The prevalence percentage of open bite in the anteriors was 2.7%, with more prevalence in Class 1 subjects (81.5%). Subjects with AOB had competent lips (81.8%), straight nasolabial angle (86.8%), and shallow palatal vault (49.5%). AOB had no significant relationship with the type of malocclusion, palatal vault, and lip competency, according to the Chi-square test. AOB and the nasolabial angle had a significant association. Both acute and right-angled nasolabial angles were commonly seen in adolescent patients with AOB. In children and adolescents visiting a private dental hospital in Chennai, the prevalence of AOB was found to be 2.7%. A significant association was observed between AOB and nasolabial angle.

Association of severity of malocclusion with socioeconomic status in the South Indian population

Malocclusion has been linked to various factors out of which certain dietary patterns and unhealthy habits are the most overlooked. The dietary patterns and unhealthy habits vary according to socioeconomic status. The present research was aimed to perform an association of malocclusion severity with socioeconomic status. This study was done in a retrospective manner and was conducted at Saveetha Dental College. A total of 241 clinical case records of the participants with malocclusion reporting for orthodontic therapy were selected and enrolled for the study. Data on the socioeconomic status and the severity of malocclusion as assessed with the Index of Orthodontic Treatment Needs (IOTNs) index were noted. All these records were collected and entered into Excel and then analyzed through statistics. Descriptive statistics and nonparametric Chi-square tests were performed. From the analysis, the proportion of IOTN Grade 1 malocclusion (30%) was found to be the highest. The highest number of patients with Grade 1 malocclusion belonged to the lower socioeconomic class. Socioeconomic status and the severity of malocclusion were significantly associated with each other. Malocclusion prevalence and severity were more among participants belonging to lower socioeconomic groups.

Severity of mandibular arch crowding in different sagittal malocclusions

Mandibular anterior crowding is caused by a variety of factors. Mandibular incisor crowding can be caused by a number of causes including incisor and molar inclination, early loss of deciduous molars, mandibular growth, and oral musculature. The study was aimed to perform an association of the lower anterior crowding severity with gender and type of malocclusion. The current study was performed in a hospital setup and data about mandibular arch crowding patients were collected from the Records management system of a Private Dental Hospital in Chennai city. All the patient data on Mandibular arch crowding were sourced and tabulated after which statistical analysis with SPSS-IBM was done. Data collection was done over a period from June 2019 to February 2021. The entire study sample size was 634 case records. The result obtained from the statistical analysis was found that nearly 46% of the patients were found to have Mandibular arch crowding with female predilection (50%). The most commonly associated age groups were children than adults (63.2%) associated with mild type of crowding (65.1%). The most commonly involved malocclusion was found to be Class 1 (88.4%) Mild imbrications of the lower arch were common and were seen mainly in subjects with Class I malocclusion. Female subjects presented with more prevalence of mandibular arch crowding when compared to male subjects. Children were more affected by crowding than adults.

ATM technique - A novel radiographic technique to assess the position of Buccal Shelf Implants

OBJECTIVES

Success of the buccal shelf implants depends on its proper placement. Radiographic techniques like cone beam computed tomography (CBCT), posteroanterior cephalogram (PA cephalogram) have been used to evaluate the position of buccal shelf implant placement. However, these techniques have disadvantages like increased radiation exposure, metal artefact, less availability in dental offices and are more expensive.The aim of Arvind's Trans Mandibular (ATM) technique is to overcome this drawback by using an intraoral periapical radiograph (IOPA) film or radiovisiography (RVG) sensor to assess the post-operative placement of buccal shelf implants.

METHODS

Radiographs were taken for four patients after the placement of buccal shelf implants. The IOPA sensor was placed beneath the lower border of the mandible using this modified extra oral technique to access the position of the buccal shelf implants in relation to the adjacent molars. The findings from the IOPA image were verified with CBCT images.

RESULTS

The radiographic images taken using ATM technique were compared with the gold standard CBCT technique. The ATM technique was able to accurately assess the postoperative bucco-lingual position of the implant with respect to the roots of molars in all the four cases. The proximity of the implant to the roots of the molar can be clearly visualized in all the cases.

CONCLUSIONS

ATM is a novel radiographic technique using IOPA radiographic film or RVG sensor to assess the post-operative bucco-lingual placement of buccal shelf implants in relation to lower molar roots.

Hereditary ovarian tumour syndromes: current update on genetics and imaging

Hereditary ovarian tumour syndromes are a diverse group of hereditary syndromes characterised by the development of specific histotypes of ovarian neoplasms. While BRCA syndromes are exclusively associated with high-grade serous carcinomas, patients with Lynch syndrome show a preponderance of endometrioid subtype of ovarian and endometrial carcinomas. Distinct non-epithelial phenotypes, such as sex cord stromal tumours with annular tubules, Sertoli-Leydig cell tumours, and small cell carcinoma of the hypercalcaemic type occur in patients with Peutz-Jeghers, DICER1, and rhabdoid tumour predisposition syndromes, respectively. Gorlin-Goltz syndrome is characterised by the development of bilateral, multiple ovarian fibromas in 14-24% of patients. Ovarian steroid cell tumours and broad ligament papillary cystadenomas are characteristically found in women with von Hippel-Lindau syndrome. Recent studies have allowed the characterisation of tumour genetics and associated oncological pathways that contribute to tumourigenesis. Implications of the diagnosis of these syndromes on screening, management, and prognosis are discussed.

A Comparative Evaluation of Intracanal Calcium Hydroxide Removal with Hand File, Rotary File, and Passive Ultrasonic Irrigation: An In Vitro Study

Aim

The aim of this study was to compare the effectiveness of hand file (K-file), rotary file (HERO shaper), and passive ultrasonic irrigation (PUI; U-file) in removing Ca(OH)₂ from the root canal.

Materials and Methods

Thirty single-rooted teeth were collected and decoronated to standardize the length to 14 mm. Cleaning and shaping were conducted using HERO shaper rotary files (up to no. 25, 4% taper). Ca(OH)₂ powder was mixed with normal saline and filled into the canals using lentulo spiral and the orifice was sealed with zinc oxide eugenol. After 7 days of incubation, samples were divided into three groups of 10 samples each: Group I (hand files)-no. 20 K-file; Group II (rotary files)-no. 25, 4% HERO shaper; Group III (PUI)-no. 20 U-file. Ca(OH)₂ paste was removed using 2 mL of 3% sodium hypochlorite solution followed by 1-minute activation of the respective file system. All the samples were finally irrigated with 17% ethylenediaminetetraacetic acid and flushed with distilled water.

Results

Ultrasonic group was more effective in removing Ca(OH)₂ followed by HERO shaper and hand file.

Conclusion

It was concluded that PUI had the highest ability to remove Ca(OH)₂ from the root canal walls.

Musculoskeletal Disorders and Mental Health-related Issues as Occupational Hazards among Dental Practitioners in Salem City: A Cross-sectional Study

Background:

Like in any other profession, dental surgeons are also afflicted by many occupational health hazards such as Musculoskeletal disorders (MSD) and mental health related issues.

Aims:

To assess the distribution of MSD and mental health related issues amidst dentists in Salem City according to age, sex and number of working hours per week.

Objectives:

A survey was organized to check the rate of occurrence of these occupational health hazards among dental practitioners in Salem city.

Materials and Methods:

The study was conducted among one hundred and fifty dentists practicing in Salem City in the form of questionnaire. Dentists were asked about any occupational disease that they suffered related to a musculo–skeletal pain and its location whether in the back, upper limbs or lower limbs. In addition to this, dentists were asked about mental stress that they had experienced.

Results:

MSD showed higher rate of prevalence compared to mental health related issues.

Conclusion:

The application of preventive measures is necessary, in view of the high rate of these disorders in the society of dental practitioners.

A comparative evaluation of microleakage of restorations using silorane-based dental composite and methacrylate-based dental composites in Class II cavities: An in vitro study

Aim:

The aim of this in vitro study was to evaluate and compare the microleakage of restorations using low shrinkage silorane-based dental composite and methacrylate-based dental composites in Class II cavity at the occlusal and gingival margins.

Materials and Methods:

Sixty mandibular molars were collected and divided into three experimental groups and one negative control group. Class II slot cavity was prepared on the mesial surface. Experimental groups were restored with Group I: silorane-based microhybrid composite, Group II: methacrylate-based nanohybrid composite, and Group III: Methacrylate-based microhybrid composite, respectively. Group IV: negative control. The samples were thermocycled, root apices were sealed with sticky wax and coated with nail varnish except 1 mm around the restoration. This was followed by immersion in 2% Rhodamine-B dye solution under vacuum at room temperature for 24 h. Then, the samples were sectioned longitudinally in the mesiodistal direction and evaluated under stereomicroscope ×40 magnification. Scoring was done according to the depth of dye penetration in to the cavity. Statistical analysis of the data was done.

Results:

The results were that no statistically significant difference in the microleakage at the occlusal margin for all the restorative materials, whereas at the gingival margin, silorane-based microhybrid composite showed less microleakage than the methacrylate-based nano- and micro-hybrid composites.

Conclusion:

In general, silorane-based microhybrid composite had less microleakage among the other materials used in this in vitro study.

Role of dietary zinc in heat-stressed poultry: a review

High ambient temperatures compromise performance and productivity through reducing feed intake and decreasing nutrient utilization, growth rate, egg production, egg quality, and feed efficiency, which lead to economic losses in poultry. Environmental stress also leads to oxidative stress associated with a reduced antioxidant status in the bird in vivo, as reflected by increased oxidative damage and lowered plasma concentrations of antioxidant vitamins (e.g., vitamins E, A, and C) and minerals (e.g., Zn). Zinc has an important role in numerous biological processes in avian and mammalian species. For instance, Zn is an essential component of many enzymes, and it has both structural and catalytic functions in metalloenzymes. Furthermore, dietary Zn is required for normal immune function as well as proper skeletal development and maintenance. One of the most important functions of Zn is related to its antioxidant role and its participation in the antioxidant defense system. This work compiles past and present information about the role of Zn in heat-stressed poultry health.

A stability-indicating HPLC assay method for docetaxel

A novel stability-indicating high-performance liquid chromatographic assay method was developed and validated for docetaxel in the presence of degradation products generated from forced decomposition studies. A gradient HPLC method was developed to separate the drug from the degradation products, using a Hichrom RPB HPLC column. Mixture of water and acetonitrile was used as mobile phase. The flow rate was 1.0 ml/min and the detection was done at 230 nm. Using the above method one can carry out the quantitative estimation of impurity namely DCT-1 and docetaxel. The developed gradient LC method was subsequently validated.

Zinc activates NF-kappaB in HUT-78 cells

Zinc is essential for human health, and its deficiency in human beings results in growth failure, immune disorders affecting Th1 functions, decreased interleukin-2 (IL-2) production, and cognitive impairment. Nearly 2000 transcription factors require zinc for their structural integrity; however, it is not known whether cellular zinc deficiency results in any change in activation of any of the transcription factors. Inasmuch as NF-kappaB binds to the promoter enhancer area of IL-2 and IL-2Ralpha genes, we investigated the effect of zinc deficiency on activation of NF-kappaB and its binding to DNA in HUT-78, a Th0 malignant human lymphoblastoid cell line. We show here for the first time that in zinc-deficient HUT-78 cells, phosphorylated IkappaB, and IKK, ubiquitinated IkappaB and binding of NF-kappaB to DNA were all significantly decreased. Zinc increased the translocation of NF-kappaB from cytosol to nucleus. We also demonstrate that the binding of recombinant NF-kappaB (p50)(2) to DNA in HUT-78 cells was zinc specific. We conclude that zinc plays an important role in the activation of NF-kappaB in HUT-78 cells.

Effects of zinc deficiency on Th1 and Th2 cytokine shifts

Nutritional deficiency of zinc is widespread throughout developing countries, and zinc-deficient persons have increased susceptibility to a variety of pathogens. Zinc deficiency in an experimental human model caused an imbalance between Th1 and Th2 functions. Production of interferon-gamma and interleukin (IL)-2 (products of Th1) were decreased, whereas production of IL-4, IL-6, and IL-10 (products of Th2) were not affected during zinc deficiency. Zinc deficiency decreased natural killer cell lytic activity and percentage of precursors of cytolytic T cells. In HuT-78, a Th0 cell line, zinc deficiency decreased gene expression of thymidine kinase, delayed cell cycle, and decreased cell growth. Gene expression of IL-2 and IL-2 receptors (both alpha and beta) and binding of NF-kappaB to DNA were decreased by zinc deficiency in HuT-78. Decreased production of IL-2 in zinc deficiency may be due to decreased activation of NF-kappaB and subsequent decreased gene expression of IL-2 and IL-2 receptors.

Duration of symptoms and plasma cytokine levels in patients with the common cold treated with zinc acetate. A randomized, double-blind, placebo-controlled trial

BACKGROUND

Adults and children in the United States get two to six colds per year. Evidence that zinc is effective therapy for colds is inconsistent.

OBJECTIVE

To test the efficacy of zinc acetate lozenges in reducing the duration of symptoms of the common cold.

DESIGN

Randomized, double-blind, placebo-controlled trial.

SETTING

Detroit Medical Center, Detroit, Michigan.

PATIENTS

50 ambulatory volunteers recruited within 24 hours of developing symptoms of the common cold.

INTERVENTION

Participants took one lozenge containing 12.8 mg of zinc acetate or placebo every 2 to 3 hours while awake as long as they had cold symptoms.

MEASUREMENTS

Subjective symptom scores for sore throat, nasal discharge, nasal congestion, sneezing, cough, scratchy throat, hoarseness, muscle ache, fever, and headache were recorded daily for 12 days. Plasma zinc and proinflammatory cytokine levels were measured on day 1 and after participants were well.

RESULTS

Forty-eight participants completed the study (25 in the zinc group and 23 in the placebo group). Compared with the placebo group, the zinc group had shorter mean overall duration of cold symptoms (4.5 vs. 8.1 days), cough (3.1 [95% CI, 2.1 to 4.1] vs. 6.3 [CI, 4.9 to 7.7] days), and nasal discharge (4.1 [CI, 3.3 to 4.9] vs. 5.8 [CI, 4.3 to 7.3] days) and decreased total severity scores for all symptoms (P < 0.002, test for treatment x time interaction). Mean changes in soluble interleukin-1 receptor antagonist level differed nonsignificantly between the zinc group and the placebo group (difference between changes, -89.4 pg/mL [CI, -243.6 to -64.8 pg/mL]).

CONCLUSION

Administration of zinc lozenges was associated with reduced duration and severity of cold symptoms, especially cough. Improvement in clinical symptoms with zinc treatment may be related to a decrease in proinflammatory cytokine levels; however, in this study, the observed differences between changes in cytokine levels in zinc and placebo recipients were not significant.

Effect of zinc supplementation on incidence of infections and hospital admissions in sickle cell disease (SCD)

Zinc deficiency is a common nutritional problem in adult sickle-cell disease (SCD) patients. Hyperzincuria and increased requirement of zinc due to continued hemolysis in SCD are probable bases for zinc deficiency in these patients. Zinc deficiency affects adversely T-helper1 (TH1) functions and cell mediated immunity and interleukin (IL)-2 production is decreased in zinc deficient subjects. We hypothesized that zinc supplementation will improve T-helper1 function and decrease incidence of infections in patients with SCD. We tested this hypothesis in 32 SCD subjects who were divided in three groups (Grs A, B, and C). Grs A (n = 11) and B (n = 10) were zinc deficient based on cellular zinc criteria and Gr C (n = 11) were zinc sufficient. Gr A subjects were observed for 1 year (baseline), following which they received zinc acetate (50 to 75 mg of elemental zinc orally daily) for 3 years. Gr B subjects were observed for 1 year (baseline), following which they received placebo for 1 year and then switched to zinc supplementation (50 to 75 mg of elemental zinc orally daily) for 2 years. Gr C subjects did not receive any intervention inasmuch as they were zinc sufficient. Prolonged zinc supplementation resulted in an increase in lymphocyte and granulocyte zinc (P = 0.0001), and an increase in interleukin-2 production (P = 0.0001), decreased incidence of documented bacteriologically positive infections (P = 0.0026), decreased number of hospitalizations and decreased number of vaso-occlusive pain crisis (P = 0.0001). The predominant pathogens isolated were staphylococci and streptococci involving the respiratory tract and aerobic gram-negative bacteria, particularly Escherichia coli, involving the urinary tract. Further confirmation of our observations will require prospective studies of zinc supplementation in a larger number of SCD patients.

Zinc and immunity

Nutritional deficiency of zinc is widespread throughout the developing countries and a conditioned deficiency of zinc is known to occur in many diseased states. Zinc is known to play an important role in the immune system and zinc deficient subjects may experience increased susceptibility to a variety of pathogens. We have studied the effects of a mild deficiency of zinc on T cells in an experimental model of human zinc deficiency. We showed that T cell functions were affected adversely even when the deficiency of zinc was mild in humans. Characteristically during zinc deficiency, the serum thymulin activity (a thymic hormone) was decreased which was restored following zinc supplementation. Our studies also showed that zinc deficiency caused an imbalance between TH1 and TH2 functions. The production of IFN-g, IL-2, TNF-a (products of TH1 cells) were decreased, whereas the production of IL-4, IL-6 and IL-10 (products of TH2) were not affected during zinc deficiency. T cell subpopulation studies revealed that the CD4+ CD45RA+ to CD4+ CD45RO+ ratio was decreased as a result of zinc deficiency, suggesting that zinc may be required for the regeneration of new CD4+ T cells. We further documented that zinc deficiency decreased NK cell lytic activity and caused a decrease in the percentage of CD8+ CD73+ T cells which are known to be predominantly precursors of cytotoxic T cells. In a suitable cell culture model our studies revealed that the gene expression of a DNA synthesizing enzyme TK was affected adversely which resulted in delayed cell cycle and decreased cell growth. The above immunological consequences of zinc deficiency may be responsible for decreased cell mediated immune functions in zinc deficient subjects.

Zinc and immunity

Nutritional deficiency of zinc is widespread throughout the developing countries and a conditioned deficiency of zinc is known to occur in many diseased states. Zinc is known to play an important role in the immune system and zinc deficient subjects may experience increased susceptibility to a variety of pathogens. We have studied the effects of a mild deficiency of zinc on T cells in an experimental model of human zinc deficiency. We showed that T cell functions were affected adversely even when the deficiency of zinc was mild in humans. Characteristically during zinc deficiency, the serum thymulin activity (a thymic hormone) was decreased which was restored following zinc supplementation. Our studies also showed that zinc deficiency caused an imbalance between TH1 and TH2 functions. The production of IFN-g, IL-2, TNF-a (products of TH1 cells) were decreased, whereas the production of IL-4, IL-6 and IL-10 (products of TH2) were not affected during zinc deficiency. T cell subpopulation studies revealed that the CD4+ CD45RA+ to CD4+ CD45RO+ ratio was decreased as a result of zinc deficiency, suggesting that zinc may be required for the regeneration of new CD4+ T cells. We further documented that zinc deficiency decreased NK cell lytic activity and caused a decrease in the percentage of CD8+ CD73+ T cells which are known to be predominantly precursors of cytotoxic T cells. In a suitable cell culture model our studies revealed that the gene expression of a DNA synthesizing enzyme TK was affected adversely which resulted in delayed cell cycle and decreased cell growth. The above immunological consequences of zinc deficiency may be responsible for decreased cell mediated immune functions in zinc deficient subjects.

Nutritional and zinc status of head and neck cancer patients: an interpretive review

In this review, we provide evidence based on our studies, for zinc deficiency and cell mediated immune disorders, and the effects of protein and zinc status on clinical morbidities in patients with head and neck cancer. We investigated subjects with newly diagnosed squamous cell carcinoma of the oral cavity, oropharynx, larynx, and hypopharynx. Patients with metastatic disease and with severe co-morbidity were excluded. Nutritional assessment included dietary history, body composition, and prognostic nutritional index (PNI) determination. Zinc status was determined by zinc assay in plasma, lymphocytes, and granulocytes. Pretreatment zinc status and nutritional status were correlated with clinical outcomes in 47 patients. Assessment of immune functions included production of TH1 and TH2 cytokines, T cell subpopulations and cutaneous delayed hypersensitivity reaction to common antigens. At baseline approximately 50% of our subjects were zinc-deficient based on cellular zinc criteria and had decreased production of TH1 cytokines but not TH2 cytokines, decreased NK cell lytic activity and decreased proportion of CD4+ CD45RA+ cells in the peripheral blood. The tumor size and overall stage of the disease correlated with baseline zinc status but not with PNI, alcohol intake, or smoking. Zinc deficiency was associated with increased unplanned hospitalizations. The disease-free interval was highest for the group which had both zinc sufficient and nutrition sufficient status. Zinc deficiency and cell mediated immune dysfunctions were frequently present in patients with head and neck cancer when seen initially. Zinc deficiency resulted in an imbalance of TH1 and TH2 functions. Zinc deficiency was associated with increased tumor size, overall stage of the cancer and increased unplanned hospitalizations. These observations have broad implications in the management of patients with head and neck cancer.

Myxoma of maxilla

A rare case of Myxoma of right maxilla in a 25 year female, presenting as-bilateral nasal obstruction with destruction of the septum and maxillary antral bone is reported.

Zinc and immune function: the biological basis of altered resistance to infection

Zinc is known to play a central role in the immune system, and zinc-deficient persons experience increased susceptibility to a variety of pathogens. The immunologic mechanisms whereby zinc modulates increased susceptibility to infection have been studied for several decades. It is clear that zinc affects multiple aspects of the immune system, from the barrier of the skin to gene regulation within lymphocytes. Zinc is crucial for normal development and function of cells mediating nonspecific immunity such as neutrophils and natural killer cells. Zinc deficiency also affects development of acquired immunity by preventing both the outgrowth and certain functions of T lymphocytes such as activation, Th1 cytokine production, and B lymphocyte help. Likewise, B lymphocyte development and antibody production, particularly immunoglobulin G, is compromised. The macrophage, a pivotal cell in many immunologic functions, is adversely affected by zinc deficiency, which can dysregulate intracellular killing, cytokine production, and phagocytosis. The effects of zinc on these key immunologic mediators is rooted in the myriad roles for zinc in basic cellular functions such as DNA replication, RNA transcription, cell division, and cell activation. Apoptosis is potentiated by zinc deficiency. Zinc also functions as an antioxidant and can stabilize membranes. This review explores these aspects of zinc biology of the immune system and attempts to provide a biological basis for the altered host resistance to infections observed during zinc deficiency and supplementation.

Zinc may regulate serum leptin concentrations in humans

OBJECTIVE

Leptin, the product of the ob gene, plays a key role in a feedback loop that maintains energy balance by signaling the state of energy stores to the brain and by influencing the regulation of appetite and energy metabolism. Zinc also plays an important role in appetite regulation. Thus, we evaluated the relationship between zinc status and the leptin system in humans.

METHODS

We studied nine healthy men with marginal zinc deficiency, induced by dietary means, before and after zinc supplementation.

RESULTS

Zinc restriction decreased leptin levels while zinc supplementation of zinc-depleted subjects increased circulating leptin levels. In addition, zinc supplementation increased IL-2 and TNF-alpha production that could be responsible for the observed increase in leptin concentrations.

CONCLUSIONS

Zinc may influence serum leptin levels, possibly by increasing the production of IL-2 and TNF-alpha.

Effects of zinc and nutritional status on clinical outcomes in head and neck cancer

The head and neck cancer patient often presents with both protein malnutrition and trace element deficiencies. Zinc has been found to be deficient in many head and neck cancer patients. In this study, pretreatment zinc status and nutritional status (measured by the Prognostic Nutritional Index [PNI]) were correlated with clinical outcomes in 47 patients. The patients were followed-up for a median of 52 mo from the time of enrollment. Our results showed that the tumor size and overall stage correlated significantly to zinc status whereas no such correlation was seen with PNI, alcohol intake, or smoking in our subjects. The results also showed that impaired zinc status was associated with an increased number of treatment morbidities, unplanned hospitalizations, and treatment delays (P < 0.05). Nutritional status was not associated with any studied outcome variable. The disease-free interval was highest for the group which had both zinc-sufficient and nutrition-sufficient status. Although our data do not prove conclusively, they do suggest that impaired zinc status at presentation may contribute to treatment morbidity, and that for an optimal mean disease-free interval, a sufficient zinc and nutritional status is required.

Cardiovascular responses to application of lower body negative pressure of male volunteers in seated position

Lower body negative pressure (LBNP) has been used to evaluate orthostatic tolerance and for studying the effects of +Gz induced physiological strain and hence has great practical significance in aerospace medicine. Cardiovascular responses in man on application to LBNP (-40 mmHg) in seated (upright) position in a specially designed LBNP chamber have been studied in eight normal healthy male volunteers between the age group of 25-36 yrs. They were subjected to -40 mmHg negative pressure in steps of -10 mmHg for a duration of 5 min each. The total duration of the experiment was 20 min. Heart rate (HR), blood pressure (BP) Cardiac output (CO) were measured and mean blood pressure (MBP) and total peripheral resistance (TPR) were computed. The results indicate a significant increase in HR (P < 0.01), SV (P < 0.01). Studies on limited number of subjects on application to LBNP (40 mmHg) in supine position have also been carried out and compared with the physiological strain induced in subjects in seated position. Study of HR, SV, CO, responses of the subjects on exposure to LBNP in seated position elicit similar response in subjects exposed to +Gz stress as reported by other workers. It is concluded that LBNP technique can be used to study the effects of +Gz induced physiological strain in man.

Zinc deficiency in head and neck cancer patients

BACKGROUND

Although a great deal of attention has been given to protein and calorie malnutrition in patients with head and neck cancer, zinc status has not been assessed properly in such patients in the past.

METHODS

In this study we characterized zinc status by cellular zinc criteria and assessed several measures of protein and calorie malnutrition in patients with head and neck cancer. We determined prognostic nutritional index (PNI) based on serum albumin, serum transferrin, triceps skin fold measures, and delayed hypersensitivity, as proposed by Buzby et al. In this study, the baseline zinc status and PNI of 60 head and neck cancer patients were correlated with the tumor size and overall stage of the disease.

RESULTS

Our results showed that the tumor size and overall stage correlated significantly to zinc status whereas no correlation was seen with PNI, alcohol intake, or smoking in our study subjects.

CONCLUSION

We conclude that zinc status is a better indicator of tumor burden and stage of the disease in head and neck cancer patients than the patients' overall nutritional status.

Decreased expression of CD73 (ecto-5'-nucleotidase) in the CD8+ subset is associated with zinc deficiency in human patients

We used flow cytometry to observe the changes in T cell populations resulting from zinc deficiency in subjects with sickle cell anemia (SCA) and in healthy human volunteers without SCA. Zinc deficiency was associated with significant decreases in cellular zinc concentration, CD4+/CD8+ ratio, and percentage of CD73+ cells in the CD8+ population. The decrease in the percentage of CD73+ cells in the CD8+ subset was significantly correlated with lymphocyte zinc concentration and was accompanied by essentially no change in the percentage of CD11b+ cells in the CD8+ subset. Daily oral zinc supplementation in nine zinc-deficient human volunteers (25 mg elemental zinc) and in seven zinc-deficient SCA subjects (50 mg elemental zinc) resulted in increases in the absolute lymphocyte count and significant increases in the CD4+/CD8+ ratio and in the percentage of CD73+ cells in the CD8+ subset. In zinc-supplemented subjects, the increase in the percentage of CD73+ cells was accompanied by a significant decrease in the percentage of CD11b+ cells in the CD8+ subset. Changes in the CD4+/CD8+ and CD73+/CD11b- cell ratios in the CD8+ subset after treatment may provide a useful diagnostic criterion for zinc deficiency in humans.

Changes in cytokine production and T cell subpopulations in experimentally induced zinc-deficient humans

We have utilized an experimental model of human zinc deficiency for study of cytokines production by TH1 and TH2 cells. Additionally, we determined ratios of CD4+ to CD8+ and CD4+ CD45RA+ to CD4+CD45RO+ cells and percentages of CD73+ T cytolytic cells in the CD8+ subset. The data were collected during baseline, at the end of the zinc-restricted period, and following zinc repletion. Our results showed that functions of TH1 cells, as evidenced by production of interferon-gamma, interleukin-2 (IL-2), and tumor necrosis factor-alpha, were decreased, whereas functions of TH2 cells (production of IL-4, IL-6, and IL-10) were unaffected by zinc deficiency. Thus an imbalance between TH1 and TH2 cells resulted because of zinc deficiency in humans. Our studies also showed that zinc may be required for regeneration of new CD4+ T lymphocytes and maintenance of T cytolytic cells. We conclude that an imbalance between TH1 and TH2 cells, decreased recruitment of T naive cells, and decreased percentage of T cytolytic cells may account for decreased cell-mediated immune functions in zinc-deficient subjects.

Trace elements in head and neck cancer patients: zinc status and immunologic functions

In this study we have assessed zinc status and zinc-dependent cell-mediated immune functions (interleukin-2 production by mononuclear cells, natural killer cell lytic activity, and interleukin-1 beta production by mononuclear cells) in adult patients with squamous cell carcinoma of the upper aerodigestive tract at diagnosis and before any therapy was instituted. Inasmuch as significant interactions between zinc, copper, and iron exist, we also assayed the plasma copper level, serum iron level, and total iron-binding capacity in our patients. We recruited 30 cancer subjects and 21 control subjects. On the basis of cellular zinc criteria, we diagnosed a mild deficiency of zinc in 53% of cancer subjects. The plasma zinc level was not decreased in our subjects. A univariate analysis was applied by use of one-way analysis of variance comparing study variables among the three study groups (controls and zinc-deficient and zinc-sufficient cancer patients) and Tukey's multiple comparison test, and we showed that interleukin-2 production and natural killer lytic activity were decreased in zinc-deficient cancer patients. Interleukin-1 beta production (ELISA assay) was increased in both zinc-deficient and zinc-sufficient groups. Plasma copper level was not different, but the iron utilization was decreased in both groups of cancer subjects. We conclude that zinc deficiency and zinc-dependent immunologic dysfunctions are present in more than half of the patients with head and neck cancer in the Detroit area.

Analysis of 24-hour ECG in patients with panic disorder

Previous evidence suggests an increased cardiovascular morbidity in patients with panic disorder. In this study, we compared 24-hour ECG in patients with panic disorder (n = 22; age: 36.1 +/- 7.6 years) and healthy controls (n = 21; age: 34.6 +/- 10.0 years). The QTc intervals during the day or night were not significantly different between patients and controls. Ventricular ectopic beats were also not significantly different between the two groups. These results do not suggest any overt cardiac arrhythmias in this age group of patients with panic disorder.

Zinc deficiency: changes in cytokine production and T-cell subpopulations in patients with head and neck cancer and in noncancer subjects

Cell-mediated immune dysfunctions and susceptibility to infections have been observed in zinc-deficient human subjects. In this study, we investigated the production of cytokines and characterized the T-cell subpopulations in three groups of mildly zinc-deficient subjects. These included head and neck cancer patients, healthy volunteers who were found to have a dietary deficiency of zinc, and healthy volunteers in whom we induced zinc deficiency experimentally by dietary means. We used cellular zinc criteria for the diagnosis of zinc deficiency. We assayed enzyme-linked immunosorbent assay the production of cytokines from phytohemagglutinin-stimulated peripheral blood mononuclear cells and assessed by flow cytometry the differences in T-cell subpopulations. Our studies showed that the cytokines produced by TH1 cells were particularly sensitive to zinc status, inasmuch as the production of interleukin-2 (IL-2) and interferon-gamma were decreased even though the deficiency of zinc was mild in our subjects. TH2 cytokines (IL-4, IL-5, and IL-6) were not affected by zinc deficiency. Natural killer cell lytic activity also was decreased in zinc-deficient subjects. Recruitment of naive T cells (CD4+CD45 RA+) and CD8+ CD73+ CD11b-, precursors of cytolytic T cells, were decreased in mildly zinc-deficient subjects. An imbalance between the functions of TH1 and TH2 cells and changes in T-cell subpopulations are most probably responsible for cell-mediated immune dysfunctions in zinc deficiency.

Zinc deficiency affects cell cycle and deoxythymidine kinase gene expression in HUT-78 cells

Although zinc is known to be involved in cell proliferation and DNA synthesis, the mechanism by which zinc may regulate these processes is not understood. We have studied the role of zinc on cell proliferation and gene expression of a DNA synthesizing enzyme, deoxythymidine kinase (TK), in a T helper human malignant lymphoblastoid cell line (HUT-78). In zinc-deficient and zinc-sufficient media, the cell doubling time (mean +/- SD) of HUT-78 was 59 +/- 8 hours and 32.6 +/- 6 hours, respectively. The effect of zinc was T cell specific, inasmuch as the cell growth of another T malignant lymphoblastoid cell line, MOLT-3 (immature T cells), was not affected by zinc deficiency. Iron, copper, or manganese did not completely correct the cell growth of zinc-deficient HUT-78 cells. TK activity and the relative accumulation of TK-mRNA were significantly decreased in zinc-deficient cells during the G1 phase of cell cycle in comparison with zinc-sufficient cells. Nuclear run-on experiments and actinomycin-D studies showed that the transcription of TK-mRNA was affected adversely by zinc deficiency. Cell cycle studies showed that more zinc-deficient cells remained in S phase and did not undergo mitosis in comparison with zinc-sufficient cells. In conclusion, our data show that zinc is a T cell-specific growth factor and that a decreased gene expression of DNA-synthesizing enzyme TK in zinc-deficient HUT-78 cells in G1 phase affected adversely the DNA synthesis in S phase and delayed cell cycle.

Zinc status and serum testosterone levels of healthy adults

Zinc deficiency is prevalent throughout the world, including the USA. Severe and moderate deficiency of zinc is associated with hypogonadism in men. However, the effect of marginal zinc deficiency on serum testosterone concentration is not known. We studied the relationship between cellular zinc concentrations and serum testosterone cross-sectionally in 40 normal men, 20 to 80 y of age. In four normal young men (27.5 +/- 0.5 y), we measured serum testosterone before and during marginal zinc deficiency induced by restricting dietary zinc intake. We also measured serum testosterone in nine elderly men (64 +/- 9 y) who were marginally zinc deficient before and after 3 to 6 mo of supplementation with 459 mumol/ d oral zinc administered as zinc gluconate. Serum testosterone concentrations were significantly correlated with cellular zinc concentrations in the cross-sectional study (lymphocyte zinc versus serum testosterone, r = 0.43, p = 0.006; granulocyte zinc versus serum testosterone, r = 0.30, p = 0.03). Dietary zinc restriction in normal young men was associated with a significant decrease in serum testosterone concentrations after 20 weeks of zinc restriction (baseline versus post-zinc restriction mean +/- SD, 39.9 +/- 7.1 versus 10.6 +/- 3.6 nmol/L, respectively; p = 0.005). Zinc supplementation of marginally zinc-deficient normal elderly men for six months resulted in an increase in serum testosterone from 8.3 +/- 6.3 to 16.0 +/- 4.4 nmol/L (p = 0.02). We conclude that zinc may play an important role in modulating serum testosterone levels in normal men.

Zinc deficiency in women, infants and children

Zinc deficiency in humans is widespread and is more prevalent in areas where the population subsists on cereal proteins. Conditioned deficiency of zinc is seen in many diseased states. A mild deficiency of zinc in pregnancy is associated with increased maternal morbidity, abnormal taste sensation, prolonged gestation, inefficient labor, atonic bleeding, and increased risks to the fetus. Among the urban poor in the US, a marginal zinc intake during pregnancy was associated with increased risk of preterm and very preterm delivery. Factors responsible for zinc deficiency in premature infants include high fecal losses of zinc, low body stores of zinc at birth, and increased zinc requirement during rapid growth. Zinc supplemented infants demonstrated improved linear growth velocity and maximum motor development scores. Marginal and moderate growth impairment in children as a consequence of inadequate zinc intake has been reported from many developed and developing countries. In one study from Japan, 21 prepubertal children were diagnosed to have zinc deficiency. The caloric intake, growth velocity, serum zinc, and plasma insulin-like growth factor-1 increased significantly in the zinc supplemented group. The clinical manifestations of zinc deficiency include growth retardation, hypogonadism in males, neurosensory disorders, cell-mediated immunological dysfunctions, and skin changes. Approximately 300 enzymes are known to require zinc for their activities. Zinc is required for DNA synthesis, cell division and protein synthesis. Several hundreds of zinc containing nucleoproteins are probably involved in gene expression of various proteins. A deficiency of zinc also affects proliferation and maturity of lymphocytes adversely.

Zinc: an overview

Zn deficiency in humans is widespread throughout the world. It is more prevalent in areas where the population subsists on cereal proteins. Conditioned Zn deficiency is seen in many disease states. Its deficiency during growth periods results in growth failure and lack of gonadal development in males. Other effects of Zn deficiency include skin changes, poor appetite, mental lethargy, delayed wound healing, neurosensory disorders, and cell-mediated immune disorders. Severe Zn deficiency, as seen in acrodermatitis enteropathica (a genetic disorder), is fatal if Zn is not administered to these patients. A clinical diagnosis of marginal Zn deficiency in humans remains problematic. Assays of Zn in granulocytes and lymphocytes provide better diagnostic criteria for marginal Zn deficiency than plasma Zn. Approximately 300 enzymes are known to require Zn for their activities. Zn is required for DNA synthesis, cell division, and protein synthesis. Recently, we learned that Zn-finger proteins are involved in genetic expression of various growth factors and steroid receptors. We suspect that several hundred Zn-containing nucleoproteins are probably involved in gene expression of various proteins. Zn deficiency adversely affects lymphocyte proliferation. This may be related to the enzymatic role of Zn in DNA synthesis and cell division. Thymulin, a thymic hormone involved in T-lymphocyte maturation, is known to be Zn dependent and is adversely affected by Zn deficiency. Thus, an adverse effect of Zn deficiency may also be in lymphocyte differentiation and maturity. Zn deficiency is known to decrease interleukin 2 production by helper T lymphocytes, and abnormalities in T-lymphocyte subpopulations have been observed in Zn-deficient humans.(ABSTRACT TRUNCATED AT 250 WORDS)

Zinc: health effects and research priorities for the 1990s

This review critically summarizes the literature on the spectrum of health effects of zinc status, ranging from symptoms of zinc deficiency to excess exposure. Studies on zinc intake are reviewed in relation to optimum requirements as a function of age and sex. Current knowledge on the biochemical properties of zinc which are critical to the essential role of this metal in biological systems is summarized. Dietary and physiological factors influencing the bioavailability and utilization of zinc are considered with special attention to interactions with iron and copper status. The effects of zinc deficiency and toxicity are reviewed with respect to specific organs, immunological and reproductive function, and genotoxicity and carcinogenicity. Finally, key questions are identified where research is needed, such as the risks to human health of altered environmental distribution of zinc, assessment of zinc status in humans, effects of zinc status in relation to other essential metals on immune function, reproduction, neurological function, and the cardiovascular system, and mechanistic studies to further elucidate the biological effects of zinc at the molecular level.

Proximal splenorenal shunts for extrahepatic portal venous obstruction in children

OBJECTIVE

The results of proximal splenorenal shunts done in children with extrahepatic portal venous obstruction were evaluated.

SUMMARY BACKGROUND DATA

Extrahepatic portal venous obstruction, a common cause of portal hypertension in children in India, is being treated increasingly by endoscopic sclerotherapy instead of by proximal splenorenal shunt. It is believed that surgery (or the operation) carries high mortality and rebleeding rates and is followed by portosystemic encephalopathy and postsplenectomy sepsis. However, a proximal splenorenal shunt is a definitive procedure that may be more suitable for children, particularly those who have limited access to medical facilities and safe blood transfusion.

METHODS

Between 1976 and 1992, the authors performed 160 splenorenal shunts in children. Twenty were emergency procedures for uncontrollable bleeding and 140 were elective procedures--102 for recurrent bleeding and 38 for hypersplenism.

RESULTS

The overall operative mortality rate was 1.9%--10% (3/160-2/20) after emergency operations and 0.7% (1/140) after elective operations. Rebleeding occurred in 17 patients (11%), and pneumococcal meningitis developed in 1 patient who recovered later. Encephalopathy did not develop in any patient. Four patients died in the follow-up period--two of rebleeding, one of chronic renal failure and a subphrenic abscess, and one of unknown causes. The 15-year survival rate by life table analysis was 95%.

CONCLUSIONS

A proximal splenorenal shunt, a one-time procedure with a low mortality rate and good long-term results, is an effective treatment for children in India with extrahepatic portal venous obstruction.

Homeostasis of zinc in marginal human zinc deficiency: role of absorption and endogenous excretion of zinc

Although biochemical and immunologic aspects of mild or marginal human zinc deficiency have been well characterized, there is a paucity of data regarding the effects of prolonged marginal zinc deficiency on zinc homeostasis. It appears that human beings are able to maintain zinc homeostasis by increasing efficiency of zinc absorption and decreasing endogenous excretion of zinc when they are subjected to short-term dietary zinc restriction. However, a mild deficiency of zinc in human beings under usual circumstances is an outcome of chronic exposure to diets low in zinc lasting for many months and years. Therefore, it is important to determine whether or not the adapted zinc homeostasis during the short duration of dietary zinc deprivation is also maintained during a prolonged period of dietary zinc restriction. We assessed the efficiency of zinc absorption as well as endogenous zinc excretion during a 6-month period of dietary zinc restriction (63.1 mumol/day) in human volunteers by using a stable zinc (70Zn). Prolonged marginal zinc deficiency did not impair the functional role of endogenous zinc excretion in zinc homeostasis, but efficiency of zinc absorption was not sustained and decreased in the majority of our volunteers when the zinc-restricted diet was continued for 6 months. Such altered mechanisms of zinc homeostasis suggest that chronic human zinc deficiency warrants reassessment of dietary zinc requirement to preserve normal zinc status in the subsets of population that are vulnerable to zinc deficiency.