Photo thermal effect graphene detector featuring 105 Gbit s-1 NRZ and 120 Gbit s-1 PAM4 direct detection

One of the main challenges of next generation optical communication is to increase the available bandwidth while reducing the size, cost and power consumption of photonic integrated circuits. Graphene has been recently proposed to be integrated with silicon photonics to meet these goals because of its high mobility, fast carrier dynamics and ultra-broadband optical properties. We focus on graphene photodetectors for high speed datacom and telecom applications based on the photo-thermo-electric effect, allowing for direct optical power to voltage conversion, zero dark current, and ultra-fast operation. We report on a chemical vapour deposition graphene photodetector based on the photo-thermoelectric effect, integrated on a silicon waveguide, providing frequency response >65 GHz and optimized to be interfaced to a 50 Ω voltage amplifier for direct voltage amplification. We demonstrate a system test leading to direct detection of 105 Gbit s^-1 non-return to zero and 120 Gbit s^-1 4-level pulse amplitude modulation optical signals.

Toward the improvement of 3D-printed vessels' anatomical models for robotic surgery training

Multi-Detector Computed Tomography is nowadays the gold standard for the pre-operative imaging for several surgical interventions, thanks to its excellent morphological definition. As for vascular structures, only the blood flowing inside vessels can be highlighted, while vessels' wall remains mostly invisible. Image segmentation and three-dimensional-printing technology can be used to create physical replica of patient-specific anatomy, to be used for the training of novice surgeons in robotic surgery. To this aim, it is fundamental that the model correctly resembles the morphological properties of the structure of interest, especially concerning vessels on which crucial operations are performed during the intervention. To reach the goal, vessels' actual size must be restored, including information on their wall. Starting from the correlation between vessels' lumen diameter and their wall thickness, we developed a semi-automatic approach to compute the local vessels' wall, bringing the vascular structures as close as possible to their actual size. The optimized virtual models are suitable for manufacturing by means of three-dimensional-printing technology to build patient-specific phantoms for the surgical simulation of robotic abdominal interventions. The proposed approach can effectively lead to the generation of vascular models of optimized thickness wall. The feasibility of the approach is also tested on a selection of clinical cases in abdominal surgery, on which the robotic surgery is performed on the three-dimensional-printed replica before the actual intervention.

From CT scanning to 3D printing technology: a new method for the preoperative planning of a transcutaneous bone-conduction hearing device

SUMMARY

The aim of the present study was to assess the feasibility and utility of 3D printing technology in surgical planning of a transcutaneous bone-conduction hearing device (Bonebridge^®) (BB), focusing on the identification of the proper location and placement of the transducer. 3D printed (3DP) models of three human cadaveric temporal bones, previously submitted to CT scan, were created with the representation of a topographic bone thickness map and the sinus pathway on the outer surface. The 3DP model was used to detect the most suitable location for the BB. A 3DP transparent mask that faithfully reproduced the surface of both the temporal bone and the 3DP model was also developed to correctly transfer the designated BB area. The accuracy of the procedure was verified by CT scan: a radiological marker was used to evaluate the degree of correspondence of the transducer site between the 3DP model and the human temporal bone. The BB positioning was successfully performed on all human temporal bones, with no difficulties in finding the proper location of the transducer. A mean error of 0.13 mm was found when the transducer site of the 3DP model was compared to that of the human temporal bone. The employment of 3D printing technology in surgical planning of BB positioning showed feasible results. Further studies will be required to evaluate its clinical applicability.

New frontiers and emerging applications of 3D printing in ENT surgery: a systematic review of the literature

3D printing systems have revolutionised prototyping in the industrial field by lowering production time from days to hours and costs from thousands to just a few dollars. Today, 3D printers are no more confined to prototyping, but are increasingly employed in medical disciplines with fascinating results, even in many aspects of otorhinolaryngology. All publications on ENT surgery, sourced through updated electronic databases (PubMed, MEDLINE, EMBASE) and published up to March 2017, were examined according to PRISMA guidelines. Overall, 121 studies fulfilled specific inclusion criteria and were included in our systematic review. Studies were classified according to the specific field of application (otologic, rhinologic, head and neck) and area of interest (surgical and preclinical education, customised surgical planning, tissue engineering and implantable prosthesis). Technological aspects, clinical implications and limits of 3D printing processes are discussed focusing on current benefits and future perspectives.

Anti-GD2-like IgM autoreactivity in multiple sclerosis patients

Seric IgM autoreactivity in 100 multiple sclerosis (MS) and 106 control (70 of whom had other neurological diseases) patients was assessed either by immunohistochemistry on normal human CNS tissue or to GD2, GD1a, GD3 by ELISA and thin layer chromatography (TLC) techniques. By double immunohistochemistry, we found that 44% of the total MS population showed seric IgM reactivity to oligodendrocytes and myelin, this finding being particularly frequent in patients with secondary progressive MS. In the non-MS cohort, positive signals were seen only in one patient. In all cases, extraction of lipids from CNS sections abolished the immunoreactivity. Among the gangliosides investigated by ELISA, anti-GD2-like IgM autoantibodies were detected in the serum of 30% of MS patients, a subgroup of whom (below 10%) reacted also with GD1a and/or GD3. More than 85% of MS cases with anti-GD2-like IgM immunoreactivity by ELISA showed also IgM anti-oligodendrocyte/myelin staining by immunohistochemistry. However, no immunostaining in MS sera was observed when gangliosides were resolved by TLC. A positive correlation with neurological disability was observed, as the Expanded Disability Status Scale of MS patients with anti-GD2-like IgM autoreactivity by ELISA was significantly worse than seronegative MS cases. The results of the present study enforce the role of glycolipids as potential autoantigens and of IgM autoantibodies in MS pathogenesis.

Comparative efficacy of selegiline versus rasagiline in the treatment of early Parkinson's disease

OBJECTIVES

The monoamine oxidase B inhibitors selegiline and rasagiline have not been compared in head-to-head clinical trials in patients with early Parkinson's disease.  The aim of this review was to compare the efficacy of these two agents in this setting.

MATERIALS AND METHODS

Randomized, placebo-controlled trials with an endpoint of the mean change from baseline in the Unified Parkinson's Disease Rating Scale (UPDRS) total score were included. Analysis included calculation of the standardized mean differences (SMDs) with 95% confidence intervals (CIs) and Forest Plot analyses for comparisons of pooled results.

RESULTS

Five studies with selegiline (n = 1029) and four with rasagiline (n = 820) were included. Treatment duration was 2.5-9 months. Both selegiline and rasagiline showed significant SMDs versus placebo (-0.690, 95% CI -0.811, -0.569 and -1.025, 95% CI -1.230, -0.820; respectively), indicating a significant effect of both drugs on UPDRS. The SMD between selegiline and rasagiline was not significantly different (SMD 0.079; 95% CI -0.010, +0.167).

CONCLUSIONS

It appears that selegiline and rasagiline have comparable efficacy in improving Parkinsonian symptoms in patients with early stage disease.

Patient-specific aortic endografting simulation: from diagnosis to prediction

Traditional surgical repair of ascending aortic pseudoaneurysm is complex, technically challenging, and associated with significant mortality. Although new minimally invasive procedures are rapidly arising thanks to the innovations in catheter-based technologies, the endovascular repair of the ascending aorta is still limited because of the related anatomical challenges. In this context, the integration of the clinical considerations with dedicated bioengineering analysis, combining the vascular features and the prosthesis design, might be helpful to plan the procedure and predict its outcome. Moving from such considerations, in the present study we describe the use of a custom-made stent-graft to perform a fully endovascular repair of an asymptomatic ascending aortic pseudoaneurysm in a patient, who was a poor candidate for open surgery. We also discuss the possible contribution of a dedicated medical images analysis and patient-specific simulation as support to procedure planning. In particular, we have compared the simulation prediction based on pre-operative images with post-operative outcomes. The agreement between the computer-based analysis and reality encourages the use of the proposed approach for a careful planning of the treatment strategy and for an appropriate patient selection, aimed at achieving successful outcomes for endovascular treatment of ascending aortic pseudoaneurysms as well as other aortic diseases.

[Trend of the asbestos related diseases mortality in workers of a company in the province Cremona which manufactured asbestos products]

The study analyzes the trend of asbestos-related diseases and mortality in workers of a company in the province of Cremona which manufactured asbestos products. It is confirmed that the exposure to a high concentration of asbestos fibers (estimated to more than 20 fibers/cc) strictly correlates with the onset of pathologies from asbestos. In the studied population were found 19 cases of neoplastic diseases (12 mesotheliomas and 7 bronchopulmonary carcinomas). This figure, compared to the company working population, which over the years has been an average of 80 units, while not enabling to calculate an incidence rate due to the lack of reliable data on population, is indicative of a very significant cause-effect relationship since these are neoplastic diseases that can still arise. So it is necessary to continue the health monitoring of formerly exposed workers and appropriate to try to extend it to all workers of the asbestos compartment.

Mutagenicity evaluation with Ames test of hydro-alcoholic solution of terpenes

Mutagenic properties of terpenes (both synthesis and plant derived) have been tested, up to now, as a single molecule. A terpenes containing hydro-alcoholic solution deriving from frankincense and myrrh resins and hyssop essential oil was assayed for mutagenicity by means of ames test. Extraction technique conducted with electromagnetic fields at room temperature enabled to obtain a solution of free active molecules that did not undergo thermal degradation and characterized by biocidal activity. In order to verify lack of mutagenic hazard in coming into contact with human, the solution was appropriately diluted and tested with Salmonella typhimurium TA98, TA1535 and YG1024 strains, both in absence and in presence of metabolic system S9. For none of the tested conditions a 2-fold increase of induced revertants, as regards to spontaneous, was registered. The ratio between induced and spontaneous His+ revertants (Mutagenic Index) was around 1.00 in all the determinations and no statistically significant differences have been identified comparing the sample and the negative control. A similar result has been obtained for the dose-response curve. In conclusion, we verified that tested terpenes solution lacks of mutagenicity on Salmonella typhimurium with and without metabolic activator so this plant extract can be safely used as biocide.

Evaluation of immunohistochemistry in identifying Bartonella henselae in cat-scratch disease

Cat-scratch disease (CSD) is largely due to infection with Bartonella henselae. Microbiologic detection is difficult, and molecular testing is not readily available. A monoclonal antibody (mAB) to B henselae has become commercially available. We evaluated the usefulness of immunohistochemical analysis (IHC) for diagnosing CSD on surgical specimens and compared these results with polymerase chain reaction (PCR) detection and serologic testing for B henselae. We studied 24 formalin-fixed, paraffin-embedded (FFPE) cases of lymphadenitis with histologic and/or clinical suspicion of CSD. Control cases included 14 cases of lymphadenopathy other than CSD. FFPE tissue sections were evaluated with an mAB to B henselae, Steiner silver stain (SSS), and PCR that targeted B henselae and Bartonella quintana. Positive cases were as follows: SSS, 11 (46%); PCR, 9 (38%); and IHC, 6 (25%). Only 2 cases (8%) were positive for all 3 studies. All control cases were negative for IHC and PCR. The diagnostic sensitivity of these 3 tests is low for CSD. SSS seems to be the most sensitive test but is the least specific. PCR is more sensitive than IHC and may, therefore, serve as a helpful second-line test on all IHC- cases.

Pathology of rituximab-induced Kaposi sarcoma flare

Background

Kaposi sarcoma (KS) flare may occur following therapy with corticosteroids, as part of the immune reconstitution inflammatory syndrome seen with highly active antiretroviral therapy (HAART), and after rituximab therapy. The exact mechanism responsible for iatrogenic KS flare is unclear.

Methods

A case of AIDS-associated cutaneous KS flare following rituximab therapy was compared to similar controls by means of immunohistochemistry using vascular makers (CD34, CD31), monoclonal antibodies to Human Herpesvirus 8 (HHV8) gene products (LNA-1, K5), as well as B-lymphocyte (CD20) and T-lymphocyte (CD3, CD4, CD8) markers.

Results

CD20+ B-cell depletion with rituximab in KS flare occurred concomitantly with activation of the HHV8 immediate early gene protein K5. KS flare in this patient was successfully treated with liposomal doxorubicin and valganciclovir.

Conclusion

Rituximab-induced KS flare appears to be related to HHV8 activation. Effective management of iatrogenic KS flare therefore depends upon the control of HHV8 viremia in conjunction with specific chemotherapy for KS.

Degree of Antioxidant Protection: A Parameter to Trace the Origin and Quality of Goat's Milk and Cheese

Traceability is an essential tool in reassuring consumers and traders that food is as safe, authentic, and of good quality as expected. Today, food traceability procedures often consist of attached documents and declarations, but scientific parameters that could objectively identify a product would be preferable. Scientific efforts in this area are mostly focused on selection and validation of experimental indicators that would be useful for tracing a food product in any step of its commercial life, describing its raw materials, processing procedures, and storage conditions. In this research, milk and cheese samples from zero grazing and grazing goats were studied to identify a tracing parameter correlated to the feeding system. In particular, alpha-tocopherol and cholesterol were analyzed by HPLC on a normal phase column and were combined to calculate the degree of antioxidant protection (DAP). This parameter, expressed as the molar ratio between antioxidant compounds and an oxidation target, is useful for tracing and distinguishing products from grazing and zero-grazing animals. Degree of antioxidant protection values greater than 7.0 x 10(-3) were found in samples from grazing goats and values lower than 7.0 x 10(-3) were found in samples from zero-grazing goats, for both milk and cheese, meaning that cholesterol was highly protected against oxidative reactions when herbage was the only feed or was dominant in the goat diet. The reliability of DAP to measure the antioxidant protection of cholesterol appeared more effective when the feeding system was based on grazing than when cut herbage was utilized indoors by animals. The DAP index was able to distinguish dairy products when the grazed herbage in the goats' diet exceeded 15%.

Efficacy and safety of oral beclomethasone dipropionate for ileal or ileal-right colon Crohn's disease of mild-to-moderate activity or in remission: Retrospective study

Although conventional glucocorticosteroids are the main treatments for active Crohn's disease, several problems are associated with steroid dependence and steroid-related adverse events. To assess the efficacy and safety of oral beclomethasone dipropionate (BDP) coated tablets in adults with mild-to-moderate Crohn's disease. Thirty-four patients (age 18-70years) with a diagnosis of Crohn's disease confirmed by conventional criteria (barium enema, clinical criteria, colonoscopy, histology) were retrospectively evaluated in the study. All subjects received a treatment schedule with BDP 5-10mg/day for 24weeks. BDP significantly (p=0.005) reduced mean Crohn's Disease Activity Index (CDAI) score from 169.6 at baseline to 123.2 after 24weeks. Clinical success was evident at 24weeks in 66.7% of patients with initial active disease, and remission was maintained at week 24 in 93.8% of patients with remission at baseline. Overall, female non-smokers had the best response to treatment. BDP was well tolerated and the only adverse events observed were nausea (n=1), facial erythema (n=1) and one patient with raised fasting blood glucose level. These results clearly suggest that oral BDP coated tablets are effective and safe for treatment of mild-to-moderate Crohn's disease of ileal or ileal-right colonic localisation.

The identification of ganglion cells in Hirschsprung disease by the immunohistochemical detection of ret oncoprotein

The absence of ganglion cells (GCs) is the primary anatomic abnormality in Hirschsprung disease. Light microscopy is the mainstay in establishing this diagnosis. However, establishing a condition of aganglionosis may be challenging on routine H&E-stained sections of colonic biopsies and resections. We studied the identification of GCs by retinoblastoma oncoprotein (ret) immunoreactivity and routine H&E light microscopy by evaluating 53 blocks from 34 patients demonstrating GCs on original H&E-stained sections and 55 blocks from 38 patients lacking GCs on original H&E-stained sections. All blocks demonstrating GCs on H&E-stained sections also were positive for GCs on ret staining (100%). In 3 blocks that were negative for GCs by H&E staining (5%), GCs were shown on ret-stained sections. Immunoreactivity for ret has comparable specificity but slightly higher sensitivity to routine light microscopic evaluation in identifying GCs. GCs are identified more readily by ret immunoreactivity than by routine morphologic examination.

MAX, a novel retrotransposon of the BEL-Pao family, is nested within the Bari1 cluster at the heterochromatic h39 region of chromosome 2 in Drosophila melanogaster

A homogeneous array of 80 tandem repeats of the Bari1 transposon is located in the pericentromeric h39 region of chromosome 2 of Drosophila melanogaster. Here, we report that the Bari1 cluster is interrupted by an 8556-bp insertion. DNA sequencing and database searches identified this insertion as a previously unannotated retrotransposon that we have named MAX. MAX possesses two ORFs; ORF1 putatively encodes a polyprotein comprising GAG and RT domains, while ORF2 could encode a 288-amino acid protein of unknown function. Alignment with the RT domains of known LTR retrotransposons shows that MAX belongs to the BEL-Pao family, which remarkable for its widespread presence in different taxa, including lower chordates. We have analyzed the distribution of MAX elements within representative species of the Sophophora subgroup and found that they are restricted to the species of the melanogaster complex, where they are heavily represented in the heterochromatin of all autosomes and on the Y chromosome.

Vimentin and leukocyte common antigen-negative molding cells in pleural effusions of patients with small cell lung carcinoma

OBJECTIVE

To determine whether the presence of vimentin and leukocyte common antigen (LCA)-negative molding cells (VLNMC) could help in identifying rare small cell lung carcinoma (SCLC) cells.

STUDY DESIGN

Thirty-four cell blocks of pleural effusions (PEs) from 26 patients with confirmed SCLC were stained immunohistochemically with vimentin and LCA antibodies and compared with hematoxylin and eosin-stained preparations.

RESULTS

VLNMC were present in 22/22 PEs originally diagnosed as positive or atypical/suspicious for SCLC. Focal vimentin staining was seen in SCLC in 10/22 cases, and 1 case showed many vimentin-positive SCLC cells. One of 11 PEs originally interpreted as negative showed rare groups of VLNMC. This was supported by a subsequent PE obviously positive for SCLC.

CONCLUSION

Immunoperoxidase stains for vimentin and LCA highlight SCLC in PEs as VLNMC; however, morphologic criteria must prevail in making the final diagnosis.

Role of liver biopsy in the diagnosis of hepatic iron overload in the era of genetic testing

We studied hepatic iron overload (HIOL) patterns in 32 patients who underwent liver biopsies and testing for HFE mutations (C282Y, H63D). Iron-stained biopsy specimens were examined for patterns of iron deposits: hereditary hemochromatosis (HH) pattern or non-HH pattern. Visual iron grade based on amount of cellular and lobular iron was evaluated. We found the HH pattern in 17 biopsy specimens (53%) and the non-HH pattern in 6 specimens (19%). HH with superimposed non-HH was noted in 9 cases (28%). In 25 patients with HFE mutations, HH alone and combined with non-HH patterns was noted in 22 specimens (88%). Visual iron grade correlated approximately with the hepatic iron index. Heavy HIOL was noted in C282Y homozygotes and 1 patient with cirrhosis without either HFE mutation. Mild steatohepatitis was found in 21 specimens (66%); it was associated with the non-HH pattern in 80% (12/15) and the HH pattern in 62% (16/26) of cases. Liver biopsy can identify pattern and grade of HIOL and associated pathology for diagnosis and management of patients with abnormal iron studies and elevated liver function test results. Genetic tests for HFE mutations and liver biopsies are complementary in the workup of these patients.

Tyrosine kinase activation in breast carcinoma with correlation to HER-2/neu gene amplification and receptor overexpression

The HER-2/neu oncogene encodes a transmembrane receptor with intrinsic tyrosine kinase activity. A pilot study was performed to investigate downstream effects of HER-2/neu (or related growth factor receptor) activation by identifying phosphorylated tyrosine. Fifty-four breast carcinomas were evaluated for HER-2/neu overexpression by the HercepTest (Dako, Carpinteria, CA) and the monoclonal CB11 antibody (Ventana, Tucson, AZ). Phosphotyrosine (an indication of tyrosine kinase activity) was detected by an antiphosphotyrosine mouse monoclonal antibody (Upstate Biotechnology, Lake Placid, NY). The gene amplification status was evaluated in 50 of the 54 cases by fluorescence in situ hybridization (FISH) using the Ventana gene probe. The HER-2/neu oncogene amplification was detected in 28% (14 of 50) of cases. Of the 14 cases showing oncogene amplification, tyrosine kinase activity was detected in 9 (64.2%) cases. There was moderate agreement between HER-2/neu gene amplification and tyrosine kinase activity (kappa = 0.43). Immunohistochemical staining of 3+ (with both HercepTest and CB11) showed better agreement with HER-2/neu oncogene amplification and increased tyrosine kinase activity than 2+ immunohistochemical staining. Overall, oncogene amplification and overexpression correlated with increased tyrosine kinase activity, supporting the mechanism of tyrosine kinase activation by HER-2/neu amplification and overexpression. However, 7 cases showing increased tyrosine kinase activity did not show gene amplification or 3+ receptor expression (by either HercepTest or CB11), raising the possibility of other growth factor receptors operating via the tyrosine kinase pathway. There was no apparent correlation between tyrosine kinase activity and hormone receptor status (estrogen or progesterone). Increased tyrosine kinase activity is more commonly associated with higher-grade tumors and thus may correlate with aggressive biologic behavior in breast carcinoma. The results of this pilot study suggest that a larger-scale investigation into downstream activation of tyrosine kinase and correlation to clinical outcome or response to Herceptin therapy may identify subsets of patients whose clinical response or outcome may be predicted by tyrosine kinase activation.

Endoscopic biopsy pathology of Helicobacter pylori gastritis. Comparison of bacterial detection by immunohistochemistry and Genta stain

OBJECTIVES

To describe the endoscopic biopsy pathology of Helicobacter pylori gastritis, compare bacterial detection by immunohistochemistry using a specific antibody with the Genta stain, and to compare the relative costs of the 2 techniques.

DESIGN

One hundred cases of gastritis identified as positive for H pylori by Genta stain and 100 cases considered negative by the same technique were stained using an anti-H pylori-specific polyclonal antibody. Laboratory reagent and labor costs for the 2 methods were compared.

RESULTS

Chronic active gastritis with lymphoid follicles was significantly associated with H pylori infection (P <.0001). The immunohistochemical method had a sensitivity of 97% and a specificity of 98% compared with the Genta stain, with strong agreement for grading density of organisms (kappa = 0.85; P <.001). Reagent costs were similar for both methods, but immunohistochemistry using an autoimmunostainer required less dedicated technical time and hence was less expensive than the Genta stain.

CONCLUSIONS

Immunohistochemistry using a specific antibody is an accurate and cost-effective method for H pylori detection in gastric biopsies.

Delayed involution of the mammary epithelium in BALB/c-p53null mice

In mammals, weaning of neonates and subsequent milk stasis initiates removal of the secretory epithelium of the mammary gland by apoptosis. The p53 tumor suppressor gene is induced rapidly following weaning of neonates, but its role in the process of involution has not been defined. Therefore, experiments were performed to identify the cell types in which the p53 gene is expressed during involution and determine the consequences of its absence in BALB/c-p53null mice. Both p53 mRNA and protein were detected in the mammary epithelium within 48 h following weaning and resulted in an eightfold increase in levels of p21WAF1 mRNA. Induction of p21WAF1 mRNA was absent in BALB/c-p53null mice, and therefore, was shown to be p53-dependent. The BALB/c-p53null mice exhibited delayed involution of the mammary epithelium, as measured by 60% greater epithelial area compared to BALB/c-p53(wt) mice through 5 days post-weaning. The delay was transient with no differences being apparent at 7 days post-weaning. Expression of the stromal protease stromelysin-1 was unaffected by the absence of p53 suggesting that stromal responses were intact. These data demonstrate that p53 participates in the first stage of involution initiated by the epithelium itself, but does not affect the second phase during which stromal proteases are induced.

1H-NMR study of reduced heme proteins myoglobin and cytochrome P450

The 1H-NMR spectra of deoxymyoglobin and reduced cytochrome P450 are analyzed by NOE spectroscopy. Progress has been made in the assignment of the hyperfine-shifted signals of deoxymyoglobin. The nuclear longitudinal-relaxation-time values indicate short electron-relaxation times whereas Curie relaxation contributes significantly to the signals linewidths. For reduced cytochrome P450 the linewidths are larger due to the Curie-relaxation contribution in a large protein. Therefore, the spectral information is poor. The electron-relaxation rates are discussed in terms of possible electronic structure.

[Quantitative bacterial ecology of normal nasal mucosa]

A quantitative research into the aerobic bacteria of human nasal cavities has been carried out; 183 healthy individuals observed, negative results 18 (9.83%). Streptococcus, Enterococcus, Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus, Streptococcus pneumoniae, Neisseria, were numerically determined and the incidence of each single species or genus exactly specified. Among gram-negative bacteria, Enterobacter, Providencia, Proteus, Citrobacter freundii, Haemophilus influenzae, Klebsiella pneumoniae, Escherichia coli, Serratia, Herella, Pseudomonas, and among the Hyphomycetes, Candida albicans have been identified and their number calculated. Diphteroid bacteria were also detected and counted; among them, the Corynebacterium pseudodiphtheriticum seemed to be the most frequent and numerous species. Finally, interference phenomena in vivo by Staphylococcus aureus and environmental and nourishment competition by Staphylococcus epidermidis, Streptococcus and Diphtheroids were noted.

[Quantitative study and typization of aerobic bacteria in the conjunctival sacs of healthy eyes]

We carried out a qualitative and quantitative bacteriological research into the conjunctives of 220 subjects in good health mostly women (180) exempt from recent or previous eyes diseases. In order to gather conjunctival bacteria we employed with a few variations Hadley's et al. (1973 [12]) method. Among the calculated bacterial flora we found as the most numerous ones Staphylococcus epidermidis (mean valor 1960/ml), then Streptococci (480/ml), Micrococci (465/ml), Diphteroides (360/ml), Enterococci (77/ml) and numerous (700/ml) Gram-positives Cocci like Sarcina, Micrococcus tetragenes, Diplococcus, and very rarely bacterial genera Gram-negatives or Iphomycetes, also numerically inferior as regards the researches of other Authors, because owen study is carried by into eyes exempt from diseases.