Food processing: a century of change.

In 1900, the population was beset with poverty, and infectious and deficiency diseases were common. The first half of the century was blighted by world wars, economic depression and post-war austerity. Nevertheless, a combination of enlightened social policy and the application of medical, nutritional and food science, resulted in substantial improvements in health, such that, by 1950, many hitherto common infectious diseases were under control, and the diet was generally nutritionally adequate. The second half of the century saw increasing economic prosperity, and unprecedented social and scientific advances. The impact on food processing was manifold: nascent technologies such as freezing and chilling were increasingly exploited, and the consumer became the major focus of a food industry that became more sophisticated, embracing automation, computerisation and new developments in, for example, drying, heat processing, controlled and modified atmosphere packaging, ingredients and quality assurance. By 1999, this had led to an industry which provided foods that were not only safe, nutritious and palatable, but which were also increasingly convenient and healthy.

Changes in fibrinogen levels in patients undergoing open and laparoscopic Nissen fundoplication.

BACKGROUND: Venous thromboembolic complications may be more common after laparoscopic surgical techniques, possibly due to changes in venous flow and blood coagulability. METHODS: This study assessed fibrinogen, cross-linked fibrin degradation products (D-dimer), prothrombin international normalized ration (INR), activated partial thromboplastic time (APTT) and platelets, during and after both open and laparoscopic Nissen fundoplication to determine whether coagulability is increased by the laparoscopic approach. RESULTS: Seven patients underwent open and thirteen underwent laparoscopic Nissen fundoplication. Fibrinogen levels following open fundoplication fell from 2.8 +/- 0.3 g/L pre-operatively to 2.0 +/- 0.3 g/L following skin incision, and then increased to 4.1 +/- 0.4 g/L on the first postoperative day. Similar changes in fibrinogen occurred following laparoscopic fundoplication (2.7 +/- 0.2, 2.5 +/ 0.2 and 3.8 +/- 0.4 g/L, respectively). No significant changes in the other coagulation indices were observed. CONCLUSIONS: These results demonstrate hypercoagulability on the first postoperative day, irrespective of the operative technique. No differences between the results following laparoscopic and open fundoplication were demonstrated.

Laparoscopic cardiomyotomy with a Dor patch for achalasia.

OBJECTIVE: To evaluate early experience with laparoscopic Heller's cardiomyotomy with placement of a Dor patch for achalasia. DESIGN: A prospective case series. SETTING: A university teaching hospital. PATIENTS: Fourteen patients (5 men, 9 women, median age 47 years) with esophageal achalasia, treated between July 1992 and July 1994. INTERVENTIONS: Laparoscopic Heller's cardiomyotomy with a Dor patch. MAIN OUTCOME MEASURES: Clinical relief of symptoms, confirmed by esophageal manometry, 24-hour ambulatory pH monitoring and barium-contrast radiography. RESULTS: Three of the 14 patients required conversion to an open procedure, and 1 underwent early laparotomy for postoperative bleeding. The median operating time was 120 minutes (range from 75 to 210 minutes), and the median duration of hospitalization was 4 days (range from 3 to 18 days). Normal physical activity was resumed after a median of 2 weeks (range from 0.5 to 6 weeks). Symptomatic dysphagia was completely relieved in 12 patients and improved in 2. Only one patient experienced symptoms of reflux postoperatively. Postoperative esophageal manometry (seven patients), 24-hour pH monitoring (five patients) and barium-meal radiography (seven patients) confirmed the clinical results. CONCLUSION: Laparoscopic Heller's cardiomyotomy with a Dor patch provides a viable alternative to open cardiomyotomy and forceful endoscopic dilatation.

Stenosis of the esophageal hiatus following laparoscopic fundoplication.

Three patients from an overall experience of more than 250 laparoscopic Nissen fundoplications have undergone further surgery for stenosis of the esophageal hiatus. This complication may be associated with diathermy dissection of the esophagus during laparoscopic mobilization.

Paraoesophageal hiatus hernia: an important complication of laparoscopic Nissen fundoplication.

Postoperative paraoesophageal hiatus hernia occurred in 17 of 253 patients who underwent laparoscopic fundoplication at five different hospitals. Ten patients have undergone subsequent surgical revision, eight by an open technique and two by laparoscopy. This complication may have important implications for the technique of laparoscopic fundoplication, as it is possible that routine posterior repair of the diaphragmatic hiatus may greatly reduce the risk. Early postoperative contrast radiology may also achieve earlier diagnosis, enabling correction to be undertaken by laparoscopy.

Laparoscopic Nissen fundoplication.

OBJECTIVE: The authors laparoscopic approach for a Nissen fundoplication is presented. SUMMARY BACKGROUND DATA: The technique has been undertaken in 155 patients over 29 months, with 137 patients having been observed for more than 3 months. METHODS: Three hundred sixty degree fundoplication was undertaken using three or four sutures to secure the wrap. Short gastric vessels were not divided, and the anterior wall of the stomach was used to construct the wrap around the esophagus with a large bougie in position. RESULTS: The operation was not completed laparoscopically in 19 patients because a satisfactory wrap could not be achieved. Ten patients undergoing laparoscopic fundoplication underwent a subsequent operation related to the laparoscopic procedure within 6 months, and there was one postoperative death. Seven other patients were readmitted to the hospital several days subsequent to their discharge, four because of pulmonary emboli. Of 137 patients who have been observed for more than 3 months, 133 patients are well and currently are free from reflux symptoms. CONCLUSIONS: In uncomplicated cases, laparoscopic fundoplication has similar advantages to laparoscopic cholecystectomy. In spite of the fact that it has not yet achieved the overall usefulness of open fundoplication, it seems likely that laparoscopic fundoplication will be used increasingly in the treatment of patients with gastroesophageal reflux disease.

Herpetic keratitis.

Herpes simplex and herpes zoster cause a wide range of acute and chronic corneal disease. The primary care clinician should be aware of the varied presentations of these two viruses. This paper presents the clinical features and treatment options that are available.

Giant cell arteritis.

Giant cell arteritis is a visually devastating disease that primarily affects the over 55 age group. This granulomatous inflammation affects large and medium-sized arteries anywhere in the body. Systemic manifestations of this disease include: jaw claudication, scalp tenderness, malaise and vertigo. Decreased appetite and/or anorexia may also be seen. Ocular manifestations may include ischemic optic neuropathy with sudden markedly reduced visual acuity. Steroid treatment is used to protect the uninvolved eye. In its classic form the disease is monitored by adjusting the steroid dosage with the erythrocyte sed rate (ESR). Prognosis for visual restoration in the involved eye is poor.

Presumed ocular histoplasmosis syndrome.

Presumed ocular histoplasmosis syndrome (POHS) is a commonly observed fungal infection. Ocular findings include peripapillary atrophy, peripheral punched-out lesions, and a macular subretinal neovascular membrane. Laser photocoagulation can be beneficial in reducing visual loss from macular scarring due to subretinal neovascular membranes. Herein we describe a patient with POHS in which laser treatment regressed a parafoveal subretinal neovascular membrane. Her vision improved from 20/70 to 20/20 in the treated eye.

Molybdenum in enzymatic and heterogeneous catalysis.

The chemistry common to molybdenum at the active centers of molybdoenzymes and at the surface of heterogeneous catalysts is described. Oxomolybdenum(VI) compounds catalyze selective oxidation of unsaturated hydrocarbons, e.g., propene to acrolein. Similarly, oxomolybdenum species take part in reactions catalyzed by molybdoenzymes, e.g., xanthine oxidase, sulfite oxidase, nitrate reductase. In these reactions H+, O2- or HO-, and electrons transfer between substrate molecules and molybdenum atoms and groups at the active centres. The chemistry involved is the acid-base and redox chemistry of molybdenum. Molybdenum disulfide catalyzes hydrogenation of unsaturated hydrocarbons, e.g., acetylene. The active site is a coordinately unsaturated molybdenum atom in a sulfur-ligand environment. The enzyme nitrogenase, which is a protein-bound iron-molybdenum sulfide, is also an excellent hydrogenation catalyst. Both catalysts exploit the chemistry of lower-valent molybdenum coordinated by sulfur. The extent to which understanding of the catalysis can be transferred between the two types of catalyst is assessed.

The composition of intracellular granules from the metal-accumulating cells of the common garden snail (Helix aspersa).

Certain cells in the hepatopancreas of the common garden snail (Helix aspersa) contain intracellular granules that are sites of metal-ion accumulation. These granules have been extracted and investigated by u.v. and i.r. spectroscopy, atomic-absorption spectroscopy, X-ray microanalysis, thermogravimetric analysis, enzymic assay and microanalysis. The deposits contain about 18% (w/w) water, 5% (w/w) organic matter and 76% (w/w) inorganic material of which the main components are Ca2+, Mg2+ and P2O7(4)-. The possible origin of these granules is discussed, as is their role in detoxifying heavy-metal ions.

Reactions of molybdenum-sulphur compounds with cyanide: chemical evolution and deactivation of molybdoenzymes.

Reactions of molybdenum-sulphur compounds with cyanide are reported which may be relevant to (1) the chemical evolution of molybdoenzymes and (2) deactivation of molybdoenzymes by cyanide. (1) With aqueous cyanide MoS2 gave thio-bridged complex anions [(Mo(CN)6)2(mu-S)]6- and [(Mo(CN)4(mu-S))2]6-. Under prebiotic conditions such complexes could have been formed similarly from molybdenite and may have been precursors of molybdoenzymes. (2) Only those compounds which contained terminal sulphur bound to molybdenum (i.e., Mo = S groups), viz. oxothiomolybdates and the complex [(Mo(mu-S)(S)(Et2NCS2))2], reacted with cyanide; thiocyanate was formed and the molybdenum underwent two-electron reduction. That the cyanolysable sulphur of xanthine oxidase reacts in the same way with cyanide suggests the presence of a Mo = S group which could be a structural feature of the enzyme or could have been formed by initial cyanolysis of a bound persulphide or cysteine residue.