bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Formaldehyde Exposure on Human Body-A Review Article
Authors: Utuh Isaac Azubuike , Ugwoha Ejikeme
Published: January 2022

Formaldehyde, a ubiquitous volatile organic compound, is used extensively in the manufacture of many products and processes across industries, yet little is known of its inherent risks in the occupations. Because of formaldehyde public health significance, many countries and regulatory agencies have issued guidelines, advisories, and regulations for its exposure. These permissible exposure limits are different for different countries and institutions, suggesting that there is currently no global agreement on what comprises safe formaldehyde exposure levels. Formaldehyde has a wide range of chronic toxicity effects affecting different cells, tissues and organs of the body including, but not limited to, neuronal, pulmonary, immunological, haematological, genetic and reproductive and developmental systems. It is also carcinogenic, nephrotoxic and hepatotoxic. Most of the mechanisms through which formaldehyde exerts its toxic effects are not clearly understood. Due to its global economic importance, formaldehyde has clearly come to stay despite its known toxicities. It is proposed that well-designed epidemiologic, in addition to mechanistic and animal studies, need to be carried out to better appreciate the systemic effects of formaldehyde exposure.
Sinonasal Anatomical Variations in Chronic Rhinosinusitis
Authors: Aboelyazeed Mohammed Moustafa , Tomoum Mohamed Osama , Elsherif Hossam Sayed , Moawad Gamea Ahmed
Published: January 2022

Background: There is a wide range of anatomical variations affecting the nose, paranasal sinuses (PNS). These variations may cause impairment of mucociliary drainage of the PNS resulting in sinusitis.

Aim: The aim of this study was to determine the incidence of anatomic variations of the different structures of the nose in a group of patients with chronic rhinosinusitis without nasal polyposis and compare them with cases didn’t have sinusitis.

Methods: This case control study included 140 patients who had diagnostic criteria of CRS according to EPOS 2020. Cases were collected from February 2020 to February 2021 from the outpatient clinic of Otorhinolaryngology Department of Tanta University Hospital. Patients were divided into two equal groups: The first group was the study group including 70 patients who had chronic rhinosinusitis as detected by Computed tomography (CT) of paranasal sinuses. The second group was the control group including 70 patients who had normal CT of paranasal sinuses.

Results: There was significant relation between the studied anatomical variations and chronic rhinosinusitis for Septal deviation, Haller cells, Supra agger frontal cell and Supra bulla frontal cell.

Conclusions: The relation between anatomical variations and sinusitis is not clear till now. Some studies showed statistically significant association between common anatomical variations and the presence of sinusitis while in other studies no statistically significant relationship. In our study there was significant statistical relation between Septal deviation, Haller cells, Supra agger frontal cell and Supra bulla frontal cell and chronic rhinosinusitis.
Case Report on Ectopic Pregnancy with Septicmia
Authors: Lacharwar Neha , Sharma Ranjana
Published: January 2022

Introduction: Ectopic pregnancy is a complication of pregnancy in which the embryo implants outside the uterus. Abdominal discomfort and vaginal bleeding are common signs and symptoms, but only around half of the women who are affected experience both. The discomfort can be severe, dull, or crampy. If there is bleeding into the abdomen, pain may radiate to the shoulder. A rapid heart rate, fainting, or shock may occur as a result of severe bleeding. The foetus, with a few exceptions, is unable to live. Obstetricians and gynaecologists face a number of obstacles when dealing with emergencies in Jehovah's Witnesses.

Main symptoms and/or important clinical findings: She is a 20-year-old woman who had an emergency diagnostic laparotomy for a ruptured ectopic pregnancy with pyosalpinx and septicemia on February 14, 2021. Her diagnostic Ultrasonography has been completed. A complete blood investigation has been completed. She was moderately symptomatic before 8 days, when she was primigravida with 2 months of pregnancy, and then she got abdomen cramps that worsened with time.

The main diagnoses, therapeutic interventions and outcomes: She is a 20-year-old woman who had a post-surgical case of Explore Laparotomy For Ruptured Ectopic Pregnancy with pyosalpinx and septicemia, as well as acute abdominal pain. Her treatment began on the day of admission with IV fluids, antibiotics and injectables. Started, advised for Zonac suppository PR, and finished all necessary research. 

Nursing Perspectives: Laboratory techniques are urgently required. In order to limit the development of treatments to enhance the outcome.

Conclusion: Although it is rare for an ectopic pregnancy to go past the first trimester, it does happen. Thus, it is necessary to rule out ruptured ectopic pregnancy in all cases of surgical abdominal urgency during pregnancy, as it is life-threatening to the mother if proper diagnosis and care are delayed. Despite the fact that early intervention saves lives and minimizes morbidity, ectopic pregnancy still accounts for 4 to 10% of all pregnancy-related deaths and is associated with a high rate of ectopic site gestations in subsequent pregnancies.
Clinical Significance of Nlr(Neutrophil Lymphocyte Ratio) and Plr(Platelet Lymphocyte Ratio) in Predicting Post Operative Complication in Major Abdominal Surgery
Authors: Shah Shyamal , Lamture Yashwant , Gharde Pankaj , Tote Darshana , Yeola Meenakshi
Published: January 2022

Background: The Expression Major abdominal surgery is defined as a lengthy surgical procedure that lasts more than 30 minutes. Gastrectomy, Pancreatectomy, Hepatectomy, Colectomy, Small Bowel Resection, Tumor Resection, And Laparoscopic Gastrointestinal Operations are among the procedures covered. The term "abdominal tumour resection" refers to a wide range of procedures used to remove benign and malignant intraabdominaltumours. There Is A Greater Tendency Of Systemic Inflammatory Reaction When The Abdomen Organs Are Exposed To The External Environment For A Long Period Of Time. As a result, the goal of this research was to concentrate on the clinical significance of the neutrophil lymphocyte ratio and platelet lymphocyte ratio in patients undergoing major abdominal surgery.

This review included a total of 15 studies conducted between 2000 and 2021. The influence of Clinical Importance Of The Neutrophil Lymphocyte Ratio and Platelet Lymphocyte Ratio In Patients Undergoing Major Abdominal Surgery has been reviewed collectively.

Results: 15 studies were included in this review were Iincluded. The present study evaluated the value of nlr and PLR as predictive markers of post operative complications in major abdominal surgeries. In the current study, we investigated the value of nlr and PLR for predicting post operative complications in patients undergoing major abdominal surgeries.

Conclusions: In Cases of Major Abdominal Surgeries, The nlr and PLR Ratio Is An Important Inflammatory Predictive Value In Assessing Post-Operative Morbidity. The platelet/lymphocyte ratio (PLR) and the neutrophil/lymphocyte ratio (NLR) are two affordable, reproducible, and quantitative measures of systemic inflammation.
A Study Protocol on Evidence Generation of Standard Nursing Protocol on Chemotherapy-Induced Neutropenia among Staff Nurses
Authors: Bawankar Payal , Ankar Ruchira
Published: January 2022

Background: Neutropenia is a condition that can occur in chemotherapy patients. Neutropenia affects roughly one out of every three chemotherapy patients. If neutropenia develops, the patient's health is affected, and the chemotherapy regimen or dose must be extended to allow the body creates new neutrophils. Even though neutropenia is common during chemotherapy, severe neutropenia is uncommon, and infections caused by it can result in significant morbidity and mortality. The protocol can help nurses make decisions about what type of care is best for their patients.

Objectives:

To report practices at baseline and post-intervention of staff nurses regarding chemotherapy-induced neutropenia.

To develop and implement the evidence-based standard nursing protocol on chemotherapy-induced neutropenia among staff nurses.

To associate the knowledge and practice score with selected demographic variables.

Materials and Methods: A Quasi-experimental research design was utilized in the current study. Pre/post-test design was utilized so the participants’ pre-test results were considered as the control for comparing their post-test results. A non-probability purposive sampling technique will be used to collect the data. The study included 100 oncology nurses’ knowledge and practice assessed by using a structured questionnaire and checklist. The study will be conducted in a selected hospital in the Wardha district.

Expected Result: This study is on evidence generation of standard nursing protocol on chemotherapy Induced neutropenia among staff nurses hence it will be assessed by evidence generation of the standard nursing protocol. Will be accepted as the results of intervention that leads to improved Knowledge regarding chemotherapy Induced neutropenia among staff nurses.
Case Report on Cervical Dysplasias
Authors: Dhawale Pragati , Takshande Vaishali , Gomase Kavita J.
Published: January 2022

Introduction: Cervical dysplasia is a precancerous disorder in which abnormal cell growth occurs on the cervix's surface lining or endocervical canal, which connects the uterus and the vaginal canal. Cervical intraepithelial neoplasia is another name for it (CIN). Clinical finding:-Abdominal pain, weight loss, fever (Temperature – 101oF).

Diagnostic Evaluation: Blood test: HB- 10.8 gm%, Total RBC count- 4.15 millions/cu mm, RDW –13.1%, Total WBC count-6100 /cu mm, Total platelets- 2.381ACS/MM3.

Cytopathology Examination: Cervical cytology Smear shows only scattered superficial and intermediated squamous cell with few neutrophils. Colposcopy Examination: Moderated dysplasia, chronic cervicitis. Colposcopy finings- cervical erosion seen on post lip,-Mosaic pattern of blood vessels seen on green filter, Aceto white areas seen at 7o’clock position, Less iodine uptake at 7o’ clock and 12o’clock positions, aceto white areas reduced as compared to previous colposcopy.

Therapeutic Intervention: Vaginal hysterectomy lateral Sphincterotomy I/V/O Cervical Dysplasia Inj. Gentamacine 80 mg iv 12 hrly, Inj. Ctax 1 gm IV 12hrly, Inj. Pan 40 mg iv 12 hrly, Inj Metro 100 ml /8 hrs, Inj. Neomal 100 ml Iv 12 hrly, Inj Pause 8 hrly, zonac suppository TDS, Tab-Gabapentin 300 mg HS, Glucose powder, protein powder 2tbsp BD with milk.

Outcomes: After treatment the patient shows improvement. Her abdominal pain and fever were relived and the surgery precancerous cells are removed, Patient condition was improved.

Conclusion: My patient was hospitalized to AVBRH gynecology unit with abdominal pain, fever, weight loss. After receivingproper therapy, her condition has improved.
A Review on Cutaneous Leishmaniasis
Authors: Shamsudheen Safeetha , Mathew Vimal , Venkateswarlu B. S. , Iqubal Risvana , Palathingal Mariya , Ali T. V. Ashira , Mathew Smiya , Maheswari D. Uma
Published: January 2022

Leishmaniasis is a vector-borne disease caused by flagellated protozoans belonging to the genus Leishmania. Cutaneous leishmaniasis (CL) is a parasitic disease transmitted by sandflies called phlebotomine that causes a variety of skin lesions. It has a wide range of clinical manifestations that are influenced by a number of unknown parasite and host factors. The disease can take many forms, ranging from self-limited and even self-healing cutaneous manifestations to fatal systemic disease. The standard treatment is pentavalent antimony. Pentavalent antimonials are the cornerstones of cutaneous leishmaniasis treatment, with novel oral and topical options on the horizon. Many lesions heal on their own and does not need to be treated. Antimonials are likely to cause a high number of reversible side effects. Other medications used in treatment include amphotericin B, pentamidine isethionate, paromomycin and antifungals. Although the cutaneous version of the disease is frequently self-limiting, it can leave considerable scarring and lead to more invasive mucocutaneous disease. As a result, treatment to prevent these problems may be considered. In endemic regions, leishmania parasites are frequently diagnosed clinically and, if possible, by microscopic inspection of lesion biopsy samples to visually confirm the aetiology. In non-endemic nations, the use of more advanced medical procedures that allow for species identification is mainly limited to research or therapeutic contexts. The application, use and adverse effects of drugs for systemic and topical treatment are also described.
Modification of Lifestyle and Weight Loss in Curing PCOS
Authors: Kumari Shambhavi , Quazi Nazli
Published: January 2022

(PCOS) is hormonal imbalance endocrine condition which harms females aged 17-40 years of age. Women suffering from PCOS are related to obesity in the abdomen and insulin resistance. Patients do does not have to be obese all the time. Women with PCOS suffer from fertility issues, hyperandrogenaemia, heavy menstrual flow, and anovulation, which is a sign of PCOS. It leads to insulin dysfunction, low metabolism, and chronic low-grade swelling. As per the Indian Council Of medical research (ICMR) data, 12.2% of adolescents in India are suffering from PCOS. Women with PCOS also suffer from anxiety, depression, lower self-esteem, and body dissatisfaction, leading to poor lifestyles. A systemic approach to a balanced diet with exercise helps in improving endocrine disorder, reproductive problems, and cardiovascular disease even without shedding much weight. Fat intake should be limited to < or approximately 30% of total calorie intake with less hydrogenated fat. Excessive carbohydrate intake having a low glycaemic index gives rise to dyslipidemia and hence leads to an increase in overall body weight with an increase in appetite, which provokes hunger and desire for carbohydrates. Energy consumption should be spread out among numerous meals each day, reducing mid-day beverages and snacks. It is advised to use drugs to regulate insulin sensitivity and elevate loss in body weight which can benefit only when used early with combined exercise and diet.
Sequences of S-surface of Human COVID-19
Authors: Alameedy Fadyia Mahdi Muslim
Published: January 2022

Aims: Diagnosing the Coronavirus and viruses that share infection for different age groups through real time PCR, as well as using the Sanger sequencing method to homology sequence identity between local human Coronavirus isolate and NCBI-BLAST submitted Coronavirus isolate.

Study Design: Cross section.

Place and Duration of Study: From the central health laboratory and quarantine centers, work was carried out in different places for the purpose of diagnosis in Al-Hakim and Al-Sadr Teaching Hospital and the Central Health Center in addition to the private laboratories, between April 2020 and July 2021.

Methodology: Diagnosing the virus through qRT- PCR, PCR and sanger sequencing. Sample: We included 300 patients (174 men, 128 women; age range 18- 83years) with from people who were infected for the first time with the Coronavirus and repeated infections with the virus with other viruses that affect the respiratory system.

Results: The current study showed that the number of cases of Coronavirus infection (110) case, Influenza virus (90) case, Parainfluenzavirus (65) case, Metapneumovirus (108)case and Rhinovirus (95)case for the period from 4-4-2020 up to 26-26 7-2021 all viruses were diagnosed through qReal time PCR technique by designing primers according to the location NCBI Regarding the sequences test, the results showed the percentage of similarity with the studied strains at a rate ranging between (99.92 - 78 %).

Conclusion: Most of the infections with the Coronavirus are common with respiratory viruses in different proportions, in addition to the fact that the age group (51-61) year is more infected, and (110) case of Influenza shares with the Coronavirus more infection and the results of Sanger sequences between(99.92 - 78 %).
Cloning and Expression of Trichoderma reesei Cellobiohydrolase I in Pichia pastoris
Authors: Godbole Shubhada , Decker Stephen R. , Nieves Rafael A. , Adney William S. , Vinzant Todd B. , Baker John O. , Thomas Steven R. , Himmel Michael E.
Published: July 2002

Pichia pastoris was transformed with the Trichoderma reesei cbh1 gene, and the recombinant enzyme was purified and analyzed kinetically and by circular dichroism. The P. pastoris rCBH I was recognized by MoAb raised to T. reesei CBH I but was found in multiple molecular weight species on SDS−PAGE gels. Carbohydrate content determination and SDS−PAGE western analysis indicated that the recombinant protein was hyperglycosylated, although a species very similar in molecular weight to the T. reesei enzyme could be isolated chromatographically. The P. pastoris rCBH I also demonstrated activity toward soluble and insoluble substrates (i.e., pNPL and Sigmacell), although at a level significantly lower than the wild‐type enzyme. More seriously, the yeast‐expressed enzyme showed non‐wild‐type secondary structure by circular dichroism. We conclude that P. pastoris may not serve as an adequate host for the site‐directed mutagenesis of T. reesei CBH I.
Anatomy of Denonvilliers' fascia and pelvic nerves, impotence, and implications for the colorectal surgeon
Authors: Lindsey I , Guy R J , Warren B F , Mortensen N J McC
Published: July 2002

Background

The development and anatomy of Denonvilliers' fascia have been controversial for many years and confusion exists about its operative appearance. Better appreciation of this poorly understood anatomy, and its significance for impotence after rectal dissection, may lead to further functional improvements in pelvic surgery.

Method

A literature review of the embryology and anatomy of Denonvilliers' fascia and impotence after pelvic rectal surgery was undertaken.

Results

Denonvilliers' fascia has no macroscopically discernible layers. The so-called posterior layer refers to the fascia propria of the rectum. The incidence of erectile and ejaculatory dysfunction after rectal excision is high in older patients, and when performed for rectal cancer. There is no consensus about the relationship of Denonvilliers' fascia to the plane of anterior dissection for rectal cancer.

Conclusion

Colorectal surgeons should focus on the important anatomy between the rectum and the prostate to improve functional outcomes after rectal excision. A classification of the available anterior dissection planes is proposed. Surgeons should be encouraged to document the plane used as well as outcome in terms of sexual function.
A quantitative model for differential motility of gliomas in grey and white matter
Authors: Swanson K. R. , Alvord E. C. , Murray J. D.
Published: July 2002

We have extended a mathematical model of gliomas based on proliferation and diffusion rates to incorporate the effects of augmented cell motility in white matter as compared to grey matter. Using a detailed mapping of the white and grey matter in the brain developed for a MRI simulator, we have been able to simulate model tumours on an anatomically accurate brain domain. Our simulations show good agreement with clinically observed tumour geometries and suggest paths of submicroscopic tumour invasion not detectable on CT or MRI images. We expect this model to give insight into microscopic and submicroscopic invasion of the human brain by glioma cells. This method gives insight in microscopic and submicroscopic invasion of the human brain by glioma cells. Additionally, the model can be useful in defining expected pathways of invasion by glioma cells and thereby identify regions of the brain on which to focus treatments.
Gestational age‐ and birthweight‐specific declines in infant mortality in Canada, 1985–94
Authors: Joseph K.S. , Kramer M.S. , Allen A.C. , Cyr M. , Fair M. , Ohlsson A. , Wu Wen S. , For The Fetal and Infant Health Study Group of the Canadian
Published: July 2002

We studied infant mortality rates in Canada within specific gestational age and birthweight categories after using probabilistic techniques to link information in Statistics Canada’s live births data base (1985–94) with that in the death data base (1985–95). Gestational age‐ and birthweight‐specific mortality rates in 1992–94 were contrasted with those in 1985–87 with changes expressed in terms of relative risks with 95% confidence intervals [CI]. Statistically significant reductions in infant mortality were observed beginning at 24–25 weeks of gestation and extended across the gestational age range to post‐term births. Crude infant mortality rates, infant mortality rates among those  500 g and among those  1000 g decreased by 22%, 25% and 26%, respectively, from 1985–87 to 1992–94. The magnitude of the reductions in infant mortality rates ranged from 14%[95% CI 7, 21%] at 24–25 weeks of gestation to 40%[95% CI 31, 47%] at 28–31 weeks. Almost all reductions in gestational age‐ and birthweight‐specific infant mortality between 1985–87 and 1992–94 were due to approximately equal reductions in neonatal and post‐neonatal mortality. Live births  42 weeks of gestation did not follow this rule; post‐neonatal mortality rates among such live births decreased significantly by 51%[95% CI 26, 68%], although neonatal mortality rates showed no significant change. The mortality reductions observed across the gestational age and birthweight range are probably a consequence of specific clinical interventions complementing improvements in fetal growth. Temporal changes in the outcome of post‐term pregnancies need to be carefully examined, especially in relation to recent changes in the obstetric management of such pregnancies.
Endothelial dysfunction in Type 1 diabetic subjects with and without microalbuminuria
Authors: Meeking D. R. , Cummings M. H. , Thorne S. , Donald A. , Clarkson P. , Crook J. R. , Watts G. F. , Shaw K. M.
Published: July 2002

Aims The primary aim of this study was to determine whether micro‐ albuminuria is associated with endothelial dysfunction in Type 1 diabetes mellitus. The secondary aim was to determine whether any reported bio‐ chemical markers of cardiovascular risk are associated with endothelial dysfunction in this group.

Methods Measurements were made of the vasodilatory responses of the brachial artery to post‐ischaemic hyperaemia and to sublingual glyceryl trinitrate (GTN) (causing endothelium‐dependent and endothelium‐independent dilation, respectively) using a high‐resolution ultrasound technique in 18 Type 1 diabetic patients with microalbuminuria, 18 age and sex‐matched normoalbuminuric Type 1 diabetic patients and 18 non‐diabetic control subjects.

Results There was a significant reduction in flow‐mediated dilation (FMD) in microalbuminuric and normoalbuminuric diabetic patients compared with control subjects (2.4% (95% confidence interval (CI) 1.0–3.8%) and 2.3% (95% CI 0.7–3.9%) respectively vs. 6.3% (95% CI 5.1–7.5%), P < 0.0001) but no difference in GTN‐mediated dilation (14.7% (95% CI 10.7–18.7%) and 15.2% (95% CI 11.2–19.2%) vs. 18.7% (95% CI 16.1–21.3%), P = 0.09). There was no significant difference in FMD, however, between the microalbuminuric group and normoalbuminuric group (P = 0.45). FMD was not significantly associated with urinary albumin–creatinine ratio, glycosylated haemoglobin, plasma glucose, lipid or lipoprotein concentrations in diabetic patients. There was a positive correlation between active transforming growth factor (TGF)‐β concentration, a novel biochemical marker of macrovascular disease, and FMD in diabetic patients (r = 0.36, P < 0.05). GTN‐mediated dilation was positively associated with HDL‐cholesterol concentration (r = 0.49, P = 0.002) but not with other biochemical variables (including active TGF‐β concentration). Active TGF‐β concentration was not associated with degree of microalbuminuria or other biochemical parameters.

Conclusions These data suggest that endothelial dysfunction occurs in Type 1 diabetic patients regardless of urine albumin status. Endothelial dysfunction appears therefore to predate the development of microalbuminuria as a marker for the development of coronary artery disease. It is also concluded that low plasma levels of active TGF‐β are associated with an impaired endothelial response and this may provide a useful tool for identifying Type 1 diabetic patients at a greater risk of coronary artery disease.
The presbyopic add. I. Magnitude and distribution in a historical context
Authors: Pointer Jonathan S.
Published: July 2002

The presbyopic addition or ‘add’ is the (binocular) spherical positive power supplement super‐imposed on any distance refractive correction to counter near vision difficulties associated with the physiological age‐related loss of accommodation and consequent recession of the near point: its necessity is first encountered in middle age. The continuous (linear) ascending trend in near lens power versus increasing age advocated since the seventeenth century is at odds with the twentieth‐century clinical observation that there is a deceleration in add requirement beyond an individual's mid‐fifties. It is shown here that this difference is reconciled – in broadly qualitative terms if not in magnitude – when typical clinical near addition data are superimposed on the accepted distance hypermetropic refractive base recorded from early middle age onwards: a continuous rising function is produced spanning most of the three decades beyond 40 years of age. This result is considered in the context of the age markings found on certain eighteenth‐century antique near vision glasses and the recommendations attached to the self‐selection of ready‐made reading glasses in the late twentieth century.
The presbyopic add. III. Influence of the distance refractive type
Authors: Pointer Jonathan S.
Published: July 2002

The possibility of the distance refractive type–emmetropia, hypermetropia or myopia–influencing the magnitude and rate of change of the presbyopic add does not seem to have received systematic consideration. To address this possibility a further series of transverse clinical data on the progression of the presbyopic add is presented. Analysis of these data reveals the influence of the distance refractive type on the presbyopic progression. Hypermetropes appear to show a two‐phase rise in add requirement whereas emmetropes follow a linear and myopes a curvilinear path over the four decades between 41 and 80 years of age. Nevertheless the magnitude of the binocular add requirement at a given age for each of the three refractive types is very similar and all three classes maintain an increasing requirement with advancing age.
Accommodation and presbyopia
Authors: Atchison David A.
Published: July 2002

The mechanism of accommodation has been studied for at least four hundred years. The most interesting aspect of accommodation is that its time course is well in advance of other physiological functions – it begins to decline by adolescence and is lost about two‐thirds of the way through the normal line span. The state of presbyopia is reached when accommodation has declined sufficiently to interfere with close tasks requiring acute vision. Presbyopia is generally considered to originate with the ‘plant’ of the accommodative system, either within the lens and its capsule or within their support structures. One of the lenticular theories, the Hess–Gullstrand theory, is distinguished from other theories by its claim that as age increases there is an increasing excess amount of ciliary muscle contraction beyond the ability of the lens and capsule to respond to it. For all other theories, the maximum possible amount of ciliary muscle contraction is always necessary to produce maximum accommodation, at least beyond the age at which it reaches its peak. From my review of the present understanding of the mechanisms of accommodation and the theories of the development of presbyopia, I conclude that there is overwhelming evidence against the Hess–Gullstrand theory and that it is unlikely that changes in the ciliary muscle contractility contribute significantly to the development of presbyopia.
Morphometric analysis of corneal endothelial giant cells in normal and traumatized corneas
Authors: Jackson A. J. , Gardiner T. , Archer D. B.
Published: July 2002

Corneal endothelial cells from normal and traumatized human, primate, cat and rabbit eyes were studied by specular microscopy. Morphometric analysis was performed on micrographs of corneal endothelium using a semi‐automated image analysis system. The results showed that under normal conditions the corneal endothelium of all four species exhibit major morphological similarities (mean cell areas: human 317 ± 32 μm2, primate 246 ± 22 μm2, cat 357 ± 25 μm2, rabbit 308 ± 35 μm2). The normal corneal endothelium in man was found to be more polymegethous than that of the other species. Trauma to cat, primate and human corneas resulted in a long‐term reduction in endothelial cell density and enhanced polymegethism. In contrast, the reparative response of the rabbit ensured the reformation of an essentially normal monolayer following injury. Endothelial giant cells were a normal inclusion in the rabbit corneal endothelium but were only significant in cat, primate and man following trauma. The presence of corneal endothelial giant cells in amitotic corneas may therefore represent a compensatory response in the absence of mitotic potential.
Contact lens fitting after photorefractive keratectomy: a comparison of two groups of patients
Authors: Astin Christine L. K.
Published: July 2002

From a research programme comparing two photorefractive keratectomy (PRK) methods, Group S using Summit ExciMed UV 200, and Group V using the VisX 20:20 excimer laser system, 10 patients from each group were recruited. They were referred 6–12 months post‐PRK for lens fitting to correct resultant ametropia or irregular astigmatism. Ablation zone diameters were: Group S, 4.5 mm; Group V, 4–6 mm. For Group S, best fit rigid gas permeable (RGP) lenses generally had a back optic zone radius (BOZR) 0.10 mm steeper than the mean keratometry reading (K) and overall diameter of 9.20–10.0 mm. For Group V best fit RGP lenses generally had a BOZR of 0.20 mm steeper than the mean K. The lenses often required large diameters to improve lens centration and extra negative power to compensate for the positive power of the central tear pool. Several patients required soft lens fitting to improve comfort and some finally opted for repeat PRK.
Research support by the British College of Optometrists
Authors: Woodward E. Geoffrey
Published: July 2002

The British College of Optometrists has now been in existence for 15 years. One of its first actions was to establish a formal system of research support. The initiation of the scheme and its subsequent expansion is described. In the first year £5,000 was allocated but current expenditure for 1994/1995 is £78,671. Research topics funded are described as are the award of higher degrees by universities and also the current occupation of former scholars. The thesis submission rate for College scholars compares well with those of the major established Research Councils.
Establishing the threshold prior to single and multiple stimulus supra‐threshold strategies
Authors: Henson David B. , Agnihotri Sarita
Published: July 2002

The purpose of this study was to establish whether the routines used to establish the threshold at the beginning of single and multiple stimulus supra‐threshold strategies yield the same values and whether data from one strategy can, therefore, be compared with those from the other without having to compensate for a difference in test intensities. Single stimulus and multiple stimulus supra‐threshold strategies were conducted on 79 subjects using a Henson 4000 perimeter. On average the multiple stimulus strategy gave a value 0.095 dB higher than the single stimulus strategy. The differences between the two strategies was so small that results from the two strategies can be compared without having to compensate for any changes in the supra‐threshold test intensity.
Broken down by age and sex. The optical correction of presbyopia revisited
Authors: Pointer Jonathan S.
Published: July 2002

New transverse clinical data are presented which describe the time course of presbyopia, as indicated by the temporal change in magnitude of the binocular spectacle add, in normally sighted male and female Caucasian subjects. An initial steep increase in add requirement beginning in the early forties becomes relatively slower but still of significance beyond the mid‐fifties. This observation is correlated with the age‐related progressive decline in the amplitude of accommodation, itself a consequence of physiological changes in the crystalline lens and capsule. The continuing need for an increase, albeit at a reduced rate, in the positive near supplement beyond the mid‐to‐late fifties (by which time little or no useful accommodation is available), is now attributed to the visually disruptive effects within the high spatial frequency domain of progressive age‐related lenticular changes. The magnification afforded by the positive add increases spatial grain and thereby enhances visibility of detail in an ageing visual system free of any gross senile pathology. A small but consistent gender difference (≃0.1 D) is revealed in presbyopic corrections: physiological and (more probable) physical bases are suggested for the observation that females require an add of greater magnitude than their age‐matched male counterparts.
Form deprivation myopia: elastic properties of sclera
Authors: Phillips J. R. , McBrien N. A.
Published: July 2002

Thinning of the posterior sclera may imply that stretching and/or weakening of the sclera plays a role in axial elongation of myopic eyes. We investigated the elastic stress‐strain properties of sclera from developing tree shrew eyes made myopic by monocular deprivation (MD) of form vision. Five days of MD induced a relative myopia (mean ± SEM) of −5.6 D ± 0.6 D (retinoscopy) and a vitreous chamber elongation (deprived minus control) of 106 ± 14 μm, n = 10 (ultrasonography). Posterior scleral test samples (2 mm wide) cut from myopic eyes were significantly thinner than their contralateral eye controls (149 ± 4 μm versus 164 ± 4 μm, n = 10, P < 0.01) when measured with a force‐controlled micrometer. However, posterior sclera from control eyes was significantly thicker than that from age‐matched normal eyes (164 ± 4 μm versus 149 ± 3μm, n = 10, P < 0.01). Under uniaxial tension, posterior scleral samples from myopic eyes failed at 18% lower load (162 g versus 198 g) and extended approximately 25% more than controls at a load corresponding to 20 mm Hg intraocular pressure. These differences were largely accounted for by the differences in scleral thickness. Finite element modelling of tree shrew eyes using the material properties summarised above, implies that simple elastic stretching of the sclera accounts for less than 20% of the observed difference in axial length between myopic and contralateral control eyes.
The Bristol Shared Care Glaucoma Study: study design
Authors: Spencer I. C. , Spry P. G. D. , Gray S. F. , Baker I. A. , Menage M. J. , Easty D. L. , Sparrow J. M.
Published: July 2002

The purpose of this study was the evaluation of community based optometric monitoring of stable glaucoma patients and glaucoma suspects compared to the routine Hospital Eye Services (HES) monitoring. Four hundred and five subjects were recruited from routine outpatient clinics at the Bristol Eye Hospital. All eligible participants were seen in the routine hospital clinic and then within two months were given a ‘Gold Standard Assessment’ (GSA) by an independent research team. Participants then visited one of 12 glaucoma‐trained optometrists, for a standard battery of tests. Randomisation resulted in 204 subjects being allocated to community care, with reviews on a six monthly basis, with 201 who remained a control group within the hospital. Referral criteria were established to enable optometric detection of apparent glaucomatous progression. A questionnaire was used to assess patient satisfaction with both care types. Additionally a cost analysis exercise was performed.
Surface wettability and hydrophilicity of soft contact lens materials, before and after wear
Authors: Shirafkan Abbas , Woodward E. Geoffrey , Port Michael J. A. , Hull Christopher C.
Published: July 2002

Surface wettability and hydrophilicity of pHEMA soft contact lenses were investigated utilising adherent liquid/laser method (ALLM) and adherent liquid/balance method (ALBM). The measurements were carried out before and after periods of 15 min to 2 h contact lens wear. Following the lens removal, the wetting angle of the contact lens of the left eyes and hydrophilicity (maximum force) of the contact lens of the right eyes of the five subjects were immediately measured, respectively, without cleaning (one value for pre‐lens wear and eight values for post‐lens wear). The wettability of soft contact lenses significantly increased after 15 min of wearing and stabilised at a maximum level after 30 min in vivo. Contact lens hydrophilicity was found to decrease as the lens was worn. The reduction continued for up to 1.5 h of wearing, for male cases, and for the female cases, the reduction continued until the end of the experiment.
Different uses of chromatic signals in patients with congenital and acquired colour vision deficiencies
Authors: Cole V. A.
Published: July 2002

Chromatic signals can be used to generate perceived colour and also to detect spatially structured objects defined only by chromatic differences. These two attributes have previously been investigated in dichromats and cerebral achromatopsic patients using a new colour vision test developed at City University that makes possible the isolation of pure chromatic signals (Barbur et al. Proc. R. Soc. LondonB 258, 327–334, 19941). We have investigated acquired colour vision changes in a 69‐year‐old patient, after conventional colour vision tests gave ambiguous results. His ability to detect an object using chromatic signals was impaired more than his ability to detect a colour change, and this impairment was greater in the right eye than in the left eye. This dissociation suggests parallel pathways may be involved in the two processes of coding chromatic signals. Recent neurological testing on the same patient has indicated the onset of multiple sclerosis. Our much earlier finding based on colour vision testing may therefore have useful diagnostic implications.
The use of coherence functions in the study of ocular mechanisms
Authors: Eadie A. S. , Pugh J. R. , Winn B.
Published: July 2002

The study of ocular mechanisms is often concerned with the possible interaction of two systems. Spectral analysis has been used previously by many investigators as a tool to investigate the interrelationships in the behaviour of two or more systems. This note demonstrates the value of computing coherence functions following spectral analysis to obtain a more rigorous tool for the investigation of synergy between two systems.
Is there a visual deficit in dyslexia resulting from a lesion of the right posterior parietal lobe?
Authors: Polikoff B. R. , Evans B. J. W. , Legg C. R.
Published: July 2002

Dyslexia has conventionally been attributed to a left hemisphere deficit affecting language skills. However, it has recently been suggested that two‐thirds of dyslexic people have a lesion of the right posterior parietal lobe (RPPL) resulting in poor oculo‐motor control. It has been reported that neurological patients with RPPL lesions commonly manifest a neglect of the left side of space and this has also been described in clinical observations of ‘visual dyslexics’. We investigated this hypothesis with a sample of 53 dyslexic children and 53 controls using a line‐bisection task. In the horizontal test condition both groups tended to transect slightly to the left of the midpoint (mean displacement 0.14 mm for controls; 0.4 mm for dyslexics). The result suggests a small right side neglect which, contrary to one report in the literature, is found here in developmental dyslexics as well as controls, and leads to the conclusion that RPPL lesion is unlikely to be a common feature of dyslexia.
Elimination and minimization of the spherical aberration of intraocular lenses in high myopia
Authors: González Concepción , Pascual Inmaculada , Bacete Angeles , Fimia Antonio
Published: July 2002

By applying Seidel aberration theory we have studied the spherical aberration of intraocular lenses in place (SIL), and the total spherical aberration of pseudophakic eyes (SIT). The optimum lens shapes for zero SIL and SIT or for minimum SIL and SIT of 12 schematic, highly myopic eyes were investigated. When the power required for emmetropization is positive, the total Seidel spherical aberration of the whole eye cannot be zero but can only be minimized. If the power of the intraocular lens is negative, the total Seidel spherical aberration of the whole eye can be made zero, and one of the optimum lens shapes would be meniscus with the convex surface towards the retina. In addition to improving the quality of the image, the lens has advantages from the physiological point of view, since it helps to maintain the structure of the eye.
Prevalence of spectacle and contact lens wear in the UK fire service
Authors: Margrain Thomas H. , Owen Christopher G. , Woodward E. Geoffrey
Published: July 2002

Despite the fact that firefighting has been shown to be a visually demanding occupation, the present visual standards for firefighters prohibit the use of spectacles or contact lenses operationally. To determine the proportion of the UK fire service currently using spectacles and contact lenses, and how many may benefit from optical correction, a questionnaire was distributed. This contained 30 questions and was sent to 1550 firefighters. The data from 1064 returned questionnaires have been analysed. The results show that approximately 20% of those serving in the fire service have used an optical correction at some time in their lives. When not working, approximately 6% of firefighters wear spectacles for distance vision and 15% wear them for reading. Only 0.4% of firefighters use contact lenses. Half of this contact lens wearing group use their lenses while on operational duty. In total, approximately 2% of firefighters use an optical correction for operational duties. The results indicate that a high visual standard at the time of entry into an occupation cannot guarantee good vision throughout an individual's career. In addition, an estimated 11 000 firefighters in the UK, who have spectacles or contact lenses, do not use them for operational duties. The present visual standards prevent this group of firefighters from obtaining their optimal visual performance at work.
An evaluation of the keratoconic cornea using computerised corneal mapping and ultrasonic measurements of corneal thickness
Authors: Owens Helen , Watters Grant A.
Published: July 2002

Reports indicate the presence of up to three independent cone shapes in keratoconus (round/oval/global) but the preponderance of one cone over another is unclear. This work evaluates keratoconic corneal topography and corneal thickness using videokeratoscopy and ultrasound pachometry, respectively. An EyeSys™ videokeratoscope (VKS) (EyeSys Laboratories, Houston, TX, USA) was used to assess the topography of 54 keratoconic eyes (27 subjects) and 27 age‐matched normals. In addition, ultrasonic pachometry measurements were made over 14 known areas in normal and keratoconic eyes. Corneal thinning was significant for all keratoconic areas measured except for the far temporal cornea. A correlation between corneal radius and thickness was evident. Analysis of cone shape revealed a potential fourth variety: the asymmetric bow‐tie cone. Further topographic evaluation of this cone entity using the VKS revealed its dependence on gaze direction which may account for apparent differences in progression patterns between round and bow‐tie cones.
Determination of the radius of curvature of the anterior lens surface from the Purkinje images
Authors: Smith George , Garner Leon F.
Published: July 2002

A new method for calculating the radius of curvature of the anterior surface of the crystalline lens from the measured heights of the Purkinje image PI and PIII is given. Equations are developed for determination of the radius of curvature of the equivalent mirror for three configurations commonly used in phakometry. The method can be applied to targets at any distance from the corneal vertex, for both a stationary target mounted independently of the camera, and for a mobile source attached to the camera where the distance of the target to the corneal vertex will change as the camera is refocused from image PI to PIII. The situation where only one recording is made of images PI and PIII, where the camera is focused on image PI, and the height of the defocused image of PIII is measured is also considered. The errors in calculating the anterior lens radius with the equivalent mirror method if no allowance is made for an object at a finite distance is examined. The new method described is an alternative to collimating targets to overcome the errors in phakometry that occur with targets at finite distances.
Optimal photographic imaging of the bulbar conjunctival vasculature
Authors: Palmer J. R. , Owen C. G. , Ford A. M. , Jacobson R. E. , Woodward E. G.
Published: July 2002

A method for imaging the conjunctiva to yield greater contrast between the vasculature and the scleral background, by optimisation of the imaging system, is described. A simple modification to the image capture system, based on first principles calculations, is shown to give images with much improved information content. This will enhance the assessment of hyperaemic changes induced by foreign materials, indicating the degree of biocompatibility, e.g. with contact lenses and ophthalmic medications. Observation of vascular abnormalities associated with pathological conditions may assist in their diagnosis and monitor progressive changes.
Reliability of visual acuity in children with reduced vision
Authors: Kheterpal Sundeep , Jones Helen S. , Auld Rosemary , Moseley Merrick J.
Published: July 2002

We examined the test‐‐retest reliability of visual acuity in 18 children referred to the Hospital Eye Service with reduced vision. Unaided distance acuities were recorded, using logarithmically scaled letter charts, on two occasions separated by an interval of one week during which no clinical intervention took place. Coefficients of repeatability were found to be ±0.25 and ±0.21 log units in left and right eyes, respectively. A further analysis of 14 subjects' data each of whom had one eye with consistently poorer acuity in both test sessions yielded coefficients of repeatability of ±0.15 and ±0.22 log units in, respectively, the better and poorer eyes. The reliability of visual acuity recorded in the better eye closely approximates to that previously found in normal adults, whilst that of the poorer eye appears more comparable to that of adult clinical populations.