Morphological development of larval cobia Rachycentron canadum and the influence of dietary taurine supplementation.

The morphological development of larval cobia Rachycentron canadum from 3 days post hatch (dph) until weaning (27 dph) was examined using S.E.M. Two groups of fish were studied: a control group (CF), reared under standard feeding protocol, and a group in which prey items were enriched with supplemental taurine (4 g l(-1) day(-1) ; TF). TF fish grew faster (P < 0·001), attained greater size (mean ±s.e. 55·1 ± 1·5 v. 33·9 ± 1·0 mm total length) and had better survival (mean ±s.e. 29·3 ± 0·4 v. 7·1 ± 1·2 %) than CF fish. Canonical variance analysis confirmed findings with respect to differences in growth between the treatment groups with separation being explained by two cranial measurements. S.E.M. revealed that 3 dph larvae of R. canadum (in both groups) possess preopercular spines, superficial neuromasts on the head and body, taste buds in the mouth, an olfactory epithelium which takes the form of simple concave depressions, and primordial gill arches. Gill filaments start to form as early as 6 dph and lamellae buds are visible at 8 dph in both groups. In CF fish, the cephalic lateral line system continues its development at 12-14 dph with invagination of both supra- and infraorbital canals. At the same time, a thorn-like or acanthoid crest forms above the eye. At 14 dph, invaginations of the mandibular and preopercular canals are visible and around 22 dph enclosure of all cranial canals nears completion. In CF larvae, however, completely enclosed cranial canals were not observed within the course of the trial, i.e. 27 dph. In TF larvae, grooves of the cephalic lateral line system form 4 days earlier than observed in CF larvae of R. canadum (i.e. at 8 dph), with enclosure commencing at 16 dph, and completed by 27 dph. Along the flanks of 6 dph larvae of either treatment, four to five equally spaced neuromasts delineate the future position of the trunk lateral line. As myomeres are added to the growing larvae, new neuromasts appear such that at 16 dph a neuromast is associated with each myomere. By 27 dph, the trunk lateral line starts to invaginate in CF larvae, while it initiates closure in TF larvae. These findings elucidate important features of the larval development of R. canadum and show that dietary taurine supplementation benefits larval development, growth and survival in this species. Moreover, they suggest a conditional requirement for taurine in larval R. canadum.

Barriers to tuberculosis care delivery among miners and their families in South Africa: an ethnographic study.

SETTING: South African miners suffer the highest tuberculosis (TB) rates in the world. Current efforts to stem the epidemic are insufficient. Historical legacies and persistent disease burden demand innovative approaches to reshape health care delivery to better serve this population. OBJECTIVE: To characterize social and behavioral health determinants for successful TB care delivery and treatment from the perspective of miners/ex-miners, health care workers and policy makers/managers. DESIGN: We conducted applied ethnography with 30 miners/ex-miners, 13 family/community members, 14 health care providers, and 47 local policy makers/managers in South Africa. RESULTS: Miners/ex-miners felt health care delivery systems failed to meet their needs. Many had experienced unnecessary physical and psychological harm due to limited health education about TB, minimal engagement in their own care, lack of trust in providers, and a system that did not value their experience. Stigma and fear associated with TB result in denial of symptoms and delays in care seeking. Health care providers and policy makers/managers felt discouraged by system constraints in providing optimal care. CONCLUSION: Our findings describe long-term effects of perpetual TB misinformation and stigma resulting from fear and disempowerment among miners and their families/communities. To reduce the TB burden, there is an urgent need to co-design a care delivery system with miners to better meet their needs.

Replacement of fish meal in cobia (Rachycentron canadum) diets using an organically certified protein.

A six-week feeding trial was conducted to evaluate the use of a yeast-based, certified organic protein source as a replacement for fish meal in diets for cobia. Five experimental diets were formulated to provide 40% crude protein and 11% dietary lipid (dry matter basis) with the yeast-based protein source replacing Special Select® menhaden fish meal at 25%, 50%, 75% and 100% of dietary protein. Ten juvenile cobia (initial weight 11.5 g/fish) were randomly stocked in triplicate 300 l circular fiberglass tanks (n = 30 treatment- 1) and hand-fed the diets based upon total tank biomass two times daily at 0900 and 1400 h. Fish were group weighed weekly to monitor performance and adjust feeding rations. Water temperature and salinity were maintained at 27 °C and 15‰, respectively. At the end of the feeding trial, weight gain, ranging from 86% to 512%, and feed conversion ratio values, ranging from 1.9 to 5.8, were significantly affected by the inclusion of the yeast-based protein source, with decreasing values as inclusion levels of the yeast-based protein source rose above 25% of dietary protein. Cobia fed the diet containing 25% of dietary protein from the yeast-based protein source had equal weight gain and feed conversion ratio values as fish fed the control diet composed of 100% fish meal (503 vs. 512 and 1.9 vs. 1.9, respectively). Biological indices including hepatosomatic index, visceral somatic index and muscle ratio were all similarly affected by inclusion of the yeast-based protein source, with significant impacts when inclusion levels rose above 25% of dietary protein. As with the weight gain and feed efficiency ratio values, fish fed the diet containing 25% of protein from the yeast-based source had similar values as those observed in the control animals. This study represents the first attempt to utilize an organically certified protein source as a replacement for fish meal in diets for juvenile cobia. Although levels of inclusion of the yeast-based protein source above 50% of dietary protein resulted in detrimental effects on production characteristics, the data clearly suggest that, at a minimum, 25% of dietary protein can be provided by this yeast-based protein in diets for cobia.

Primary small-cell cancer of the esophagus.

Primary small-cell cancer of the esophagus is a rare tumor that disseminates early with a uniformly poor prognosis if untreated. Sixteen patients with malignant dysphagia referred to the Thoracic Surgical Unit, City Hospital, Edinburgh, within a 10-year period had a diagnosis of primary small-cell cancer of the esophagus. Seven patients underwent subtotal esophagectomy or esophagogastrectomy, either alone or with adjuvant chemotherapy or radiotherapy, with a mean survival of 20 months (standard deviation 35.4 months, range 2 weeks to 96 months). The remaining nine patients had disseminated disease when they were first seen and were treated symptomatically by intubation alone (1 patient), intubation and palliative chemotherapy or radiotherapy (3 patients), palliative chemotherapy (2 patients), palliative radiotherapy (1 patient), or no therapy (2 patients), with a mean survival of 4.8 months (standard deviation 2.6 months, range 2 to 9 months). Patients seen with this aggressive tumor should be assessed urgently for evidence of metastatic spread and then offered resection in combination with chemotherapy if they are otherwise fit for operation. This treatment regimen has given us one long-term survivor (96 months) who, we believe, is the only patient to have been cured of this condition. Patients seen with disseminated disease should have symptomatic treatment of the dysphagia combined with palliative chemotherapy.

Comparison of hospitalization between nursing home and community residents.

The authors prospectively identified 96 consecutive nursing home residents (NHR) admitted to the medical wards of their affiliated hospitals to determine the outcome of hospitalization for these patients in comparison with 88 admissions in a similarly aged community residents (CR) population. Nursing home and community resident groups were similar in age, sex, marital status, and distribution among the four study hospitals. Dementia was a more common preexisting diagnosis in NHR than in CR. Reasons for admission differed between the two groups. Although NHR experienced a longer hospitalization than CR, frequency and duration of intensive care unit admissions were similar. Fatal outcome occurred more commonly in NHR compared with CR (27 v 11%, P less than .001). Predictors of mortality were examined. Nursing home residents also experienced a higher mortality than CR within the six months after hospitalization (35 v 20%, P less than .005).

Potential complications of vascular stapling in thoracoscopic pulmonary resection.

In a series of 57 patients undergoing thoracoscopic pulmonary lobectomy, 2 required expeditious conversion to open thoracotomy when a stapling device (Endo-GIA 30 V3; Autosuture, Ascot, UK) used on the main right lower pulmonary artery in 1 case and on the left superior pulmonary vein in the other cut but failed to staple the vessel involved. In both instances the vessel was successfully controlled while a thoracotomy was performed and the involved vessel was oversewn. Both patients made an uncomplicated postoperative recovery. As the number of thoracoscopic pulmonary resections increases, it is likely that similar episodes will occur in the future. These cases strongly emphasize the fact that patients undergoing this procedure should do so in a center specializing in thoracic surgery where there is the necessary surgical expertise and equipment to deal with such potentially life-threatening vascular complications.

The "annular sandwich": a simple method of reinforcing a friable mitral valve annulus.

In 6 patients undergoing prosthetic mitral valve replacement a ring of Teflon felt, instead of conventional Teflon pledgets, was used because of concern about seating a new prosthesis in a disrupted friable mitral valve annulus. The technique avoided the potential risk of pledget loss in the event of suture breakage and, in these patients, prevented postoperative paraprosthetic mitral valve regurgitation.

Esophagectomy for carcinoma in the octogenarian.

BACKGROUND: Esophageal carcinoma is predominantly a disease of the elderly, a group often only considered for palliative therapies. METHODS: A case note review identified 31 octogenarians undergoing resection for carcinoma of the esophagus or gastric cardia over a 12-year period ending December 1994. RESULTS: Nineteen patients made either an uncomplicated postoperative recovery (n = 12) or suffered minor complications (n = 7). Of the 12 patients who suffered moderate or severe complications, 5 died (in-hospital mortality, 16%). The deaths included 2 of 3 patients who underwent emergency operation for esophageal perforation and 3 of 28 patients who underwent elective esophagectomy (elective mortality rate, 10.7%). Nineteen of the 26 survivors (73%) experienced no further dysphagia. The 5-year survival rate was 17%. CONCLUSIONS: Elective esophageal resection can be performed safety in selected octogenarians who have no or few coexisting medical problems and present with a localized carcinoma that is technically easy to resect. Patients undergoing emergency operations or in whom moderate or severe postoperative complications develop often have poor physiologic reserve and are therefore at risk of early postoperative death.

A pedunculated intraluminal foregut reduplication cyst of the proximal esophagus.

A 66-year-old woman with a 3-month history of progressive dysphagia underwent transoral excision of a pedunculated cyst arising in the proximal esophagus. Histologic examination confirmed a pedunculated intraluminal foregut reduplication cyst. She remains well 1 year after excision with no recurrence of dysphagia.

Effect of blood transfusion on survival after esophagogastrectomy for carcinoma.

BACKGROUND: There is growing evidence that blood transfusion is associated with clinical factors that can lead to transfusion-induced immunosuppression. This effect can be beneficial or deleterious. METHODS: The effect of perioperative allogeneic blood transfusion on survival was studied retrospectively in 524 patients who were discharged from the hospital after esophagogastrectomy for carcinoma performed in a single unit over a 10-year period. RESULTS: The median operative blood loss for the series was 500 mL (range, 50 to 3,750 mL). Three hundred thirty-five patients (64%) received a perioperative allogeneic blood transfusion related to esophagogastrectomy, and 189 (36%) did not. The median perioperative blood transfusion administered was 900 mL (range, 300 to 12,950 mL). Perioperative allogeneic blood transfusion was associated with reduced survival for patients in stage III (p < 0.05) at 1 year, but no significant difference was found in this stage at 3 or 5 years after resection. Stage III disease accounted for 250 (48%) of the 524 patients discharged. CONCLUSIONS: Although perioperative allogeneic blood transfusion does not affect long-term survival after esophagogastrectomy for carcinoma, it does have a significant association with short-term survival in a group whose overall survival is often limited after resection. Attention should be directed toward minimizing operative blood loss and transfusing only for factors known to be clinically important, such as oxygen delivery and hemodynamics, not arbitrary hemoglobin levels.

The use of bovine internal mammary artery (Bioflow) grafts in coronary artery surgery.

Over a 3-year period 17 patients underwent a total of 25 coronary artery bypass grafts utilising bovine internal mammary artery [BIOFLOW]. Three patients died in the peri-operative or early post-operative period allowing detailed information to be gathered on 14 patients. Seven patients who had had a total of 11 Bioflow grafts implanted underwent post-operative coronary angiography at a mean time of 19 months after surgery revealing occlusion in all the Bioflow grafts. Two patients who underwent aortic valve replacement combined with single Bioflow grafts were symptom-free and refused re-study. Two patients who had three coronary grafts each, including single Bioflow grafts, refused re-study though one of them had recurrent anginal symptoms. Two patients, one with recurrent anginal symptoms, who had a total of four Bioflow grafts were considered unfit for restudy on medical (non-cardiac) grounds. One patient with two Bioflow grafts and recurrent symptoms refused long-term follow-up. Despite reports of good early patency rates with the Bioflow graft, we have not found this to be the case even when patients were anticoagulated post-operatively. We do not recommend the use of this graft as early occlusion is to be expected, which may result in an early return of anginal symptoms.

Video-assisted thoracoscopic pulmonary surgery--current status and potential evolution.

The current status of video-assisted thoracoscopic surgery (VATS) of the lung has been reviewed. The published data support the view that VATS pulmonary surgery is feasible and safe. It is associated with decreased perioperative pain and opiate requirement, better postoperative pulmonary function, and probable overall neutral cost impact. A VATS approach is functionally superior to open thoracotomy for wedge resection, pneumothorax surgery and bullous lung disease and may allow surgical intervention in patients with pulmonary function which is in adequate for open resection. Major VATS pulmonary resection with lobectomy and pneumonectomy can be performed for early malignant disease without compromising established surgical principles. Specific training is needed in VATS surgery and background skills in general thoracic surgery are necessary to underwrite major interventions. Decreased cytokine activation and enhanced post surgical immune function may prove to be long-term benefits of VATS surgery.

Acute phase responses following minimal access and conventional thoracic surgery.

OBJECTIVES: Major thoracic surgery is associated with trauma-related immunological changes. These may impair anti-tumour immunity. We hypothesize that the reduced operative trauma associated with a video-assisted thoracic surgery (VATS) approach may decrease acute phase responses and, consequently, lead to better preservation of immune function. This prospective randomized study compared the effects of conventional open thoracic surgery and VATS on acute phase responses in patients undergoing pulmonary lobectomy. METHODS: Acute phase indicators were analyzed in patients undergoing lobectomy for suspected bronchogenic carcinoma. Surgery was prospectively randomized to pulmonary lobectomy by VATS or limited postero-lateral thoracotomy. Blood was taken pre-operatively and at 4, 24, 48, 72, 120 and 168 h post-operatively for analysis of C-reactive protein (CRP; 41 patients: open, n=22; VATS, n=19) interleukin (IL)-6, tumour necrosis factor (TNF) receptors (TNF-sR55, TNF-sR75) and P-selectin (24 patients: open, n=12; VATS, n=12). Samples taken at 48 and 168 h were also analyzed for phagocyte reactive oxygen species (ROS) production (25 patients: open, n=16; VATS, n=19). RESULTS: Surgery increased acute phase responses. VATS was associated with lower CRP and IL-6 levels. In the open surgery group, significant increases in ROS in neutrophils (up to 36% greater than before surgery, n=12, P<0.02-0.05) were detected at 2 days after surgery, but in the VATS group, the increase after surgery (of up to 17%, n=18) did not reach significance. Similarly, monocyte ROS increases of up to 25% in the mean ROS in the open surgery group and of up to 17% in the VATS group were detected on days 2 and 7 after surgery. CONCLUSIONS: VATS pulmonary lobectomy is associated with reduced peri-operative changes in acute phase responses. This finding may have implications for peri-operative tumour immuno-surveillance in lung cancer patients.

Video-assisted thoracoscopic pneumonectomy for bronchial carcinoid tumor in a 14-year-old girl.

A 14-year-old girl with a carcinoid tumor of the proximal right bronchus intermedius underwent a video-assisted thoracoscopic pneumonectomy. She was fully ambulant within 48 hours of surgery, had less pain than that normally associated with standard thoracotomy, and was discharged on the 7th postoperative day.

Primary malignant melanoma of the esophagus.

Primary malignant melanoma of the esophagus, first recognized as a primary tumor by de la Pava et al. in 1963, is rare. It usually presents as an aggressive polypoidal darkly colored or non-pigmented tumor in the mid to lower esophagus which may be diagnosed preoperatively by the use of immunohistochemical stains such as HMB-45 (melanoma specific antigen). The treatment of choice is surgical resection however the overall prognosis is poor with only 4 per cent of patients surviving 5 years.

Continued experience with thoracoscopic major pulmonary resection.

Between April 1992 and March 1995, 83 patients underwent video-assisted (VATS) thoracoscopic major pulmonary resection (lobectomy: 72, bilobectomy: 4, or pneumonectomy: 7). Conversion to open thoracotomy was required in a further 21 cases (rate=20.2%). There was no in unit mortality; 2 patients died within 30 days (1.9% overall). Analysis (median values) of the VATS lobectomy cases demonstrated; operation time - 135 minutes; blood loss - 80 mls; High Dependency stay - 38 hours; total postoperative stay - 7 days. Comparison between 70 VATS lobectomies and a simultaneous group of 110 open thoracotomy cases confirmed reduced postoperative morphine consumption (83 mg open vs 57 mg VATS; p<0.001). One pneumonectomy patient exhibited a transient sympathetic dysaesthesia and one lobectomy patient developed a mild post thoracotomy pain syndrome. Long-term follow-up of VATS lobectomy for patients with primary bronchogenic carcinoma (49) revealed 1 bronchogenic cancer related death during an overall mean follow-up of 16.5 months.

When lightning strikes. Pathophysiology and treatment of lightning injuries.

Lightning accidents are responsible for several hundred deaths and thousands of injuries each year in this country. Survivors sustain a variety of cardiac, neurologic, musculoskeletal, and dermatologic injuries. Eye and ear injuries are also occasionally noted. Education on how to minimize the possibility of such an accident is the best method of dealing with the problem. When prevention fails, prompt cardiopulmonary resuscitation and supportive treatment for the patient's particular injury are indicated.