PubMed Health⌕ Search

Biomedical subjects

M A Hoffman

Publications and source records attributed to M A Hoffman.

At least 55 records · Page 3Linked to original sources

Cytomegalovirus immune globulin prophylaxis in liver transplantation. A randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To study the effect of cytomegalovirus immune globulin (CMVIG) on prevention of cytomegalovirus (CMV) disease and its complications in patients receiving liver transplants. DESIGN: Randomized, multicenter, placebo-controlled, double-blind trial. SETTING: Four university-affiliated transplant centers in Boston (Boston Center for Liver Transplantation). PATIENTS: One hundred forty-one liver transplant recipients completed the study. INTERVENTION: CMVIG or placebo (1% albumin) given in a dose of 150 mg/kg body weight within 72 hours of the transplant, then at weeks 2, 4, 6, and 8, and at 100 mg/kg at weeks 12 and 16. MEASUREMENTS: Patients were observed for 1 year after transplantation for the development of CMV infection, disease, pneumonia, as well as for opportunistic fungal infections, graft survival, and mortality. Weekly cultures were taken of urine, buffy coat, and throat wash for CMV for 2 months, then monthly, and at any clinical illness. RESULTS: Using a Cox proportional hazards model, CMVIG was shown to reduce severe CMV-associated disease (multi-organ CMV disease, CMV pneumonia, or invasive fungal disease associated with CMV infection) from 26% to 12% (relative risk, 0.39; 95% CI, 0.17 to 0.89). When we controlled for the use of monoclonal antibodies to T cells (OKT3), CMVIG use was still protective (relative risk, 0.39; CI, 0.17 to 0.90). Rates of CMV disease were reduced from 31% to 19% (relative risk, 0.56; CI, 0.3 to 1.1) in CMVIG recipients although no effect on rates of CMV infection, graft survival, or patient survival at 1 year were shown. When we controlled for the urgency of transplantation and OKT3 use, a reduction in CMV disease (relative risk, 0.22; CI, 0.06 to 0.81) was shown for globulin recipients for all serologic groups except for the highest risk group (the CMV-seropositive donor, CMV-seronegative group). CONCLUSION: CMVIG reduced the rate of severe CMV-associated disease in patients undergoing orthotopic liver transplantation. No effect of CMVIG on CMV donor-positive, recipient-negative liver transplant recipients was shown, suggesting a need for additional prophylactic strategies.

Acyclovir↗

Gastroesophageal reflux in children.

Operations for the control of complicated gastroesophageal reflux in children are commonly performed procedures in large pediatric centers. The comprehensive diagnostic scheme includes radiologic and endoscopic work-up coupled with extended pH probe analysis. Medical therapy remains the principle form of management, with surgery reserved for treatment failure.

Child↗

Experimental volume replacement through lower extremity veins.

Hypovolemic shock was produced in anesthetized pigs by removal of 40% of blood volume over 10 minutes. Following blood loss, the inferior vena cava (IVC) was occluded below the renal veins to simulate the hemodynamics of emergency surgical treatment. Control animals were not treated. Experimental animals received intravenous lactated Ringer's solution equal to three times the blood loss given through catheters either in the IVC or the superior vena cava (SVC) to determine if lower extremity access would be efficacious in this model. To define the path taken by the resuscitation fluids, an additional group of animals received technetium-99m-labelled crystalloid through lower extremity catheters with continuous recording of isotope counts in the IVC and right atrium. The treated animals in all experimental groups had significant improvements in mean arterial pressure, cardiac output, and pH compared with controls. There was no significant difference in hemodynamic response in animals receiving volume replacement through the IVC compared with the SVC. When fluid was infused below a clamped IVC, the arrival of isotope in the right atrium was delayed only 1.5 seconds. We conclude that in a model simulating emergency control of potentially lethal hemorrhage, the beneficial effects of fluid resuscitation are unrelated to the site of venous access. Lower extremity veins provide a valuable site for volume replacement even with IVC occlusion. These findings should have direct application to resuscitation and surgical care of seriously injured patients.

Animals↗

Mechanisms by which interferon potentiates chemotherapy.

IFNs potentiate the activity of multiple chemotherapy drugs in vitro; improved activity has been noted with 5-FU and IFN-alpha against colon carcinoma and with IFN-alpha and DTIC against melanoma. The mechanisms whereby interferon potentiates the activity of chemotherapeutic drugs are complex, and different mechanisms may be operative with different drugs and against different tumors. Both indirect immunoaugmentative effects of interferon and direct biochemical modulation of the drugs (as documented in detail with 5-FU) may play a role; further elucidation of these mechanisms will enable us to optimally utilize the combination of interferon and antineoplastic agents.

Animals↗

Assessment of health and stress levels in school personnel.

The purpose of this study was to evaluate current health status and awareness of individual health risk factors of school personnel using a health risk appraisal and select screening tools. One hundred eleven elementary and junior high school faculty and staff participated in a health screening and computerized assessment to evaluate individual health status. Analysis revealed significant findings for cholesterol, HDL cholesterol ratio, mean arterial pressure, and perceived stress. Results from this study will assist school nurses in defining target health behavior areas for health promotion/wellness activities.

Adult↗

A multifocal comparison of health status and physical readiness test results of Navy personnel.

Many health risk factors are behaviorally related and therefore subject to modification. This study compared health risk appraisal (HRA) age, chronological age, identified risk factors, physiological measures, and demographic variables with Physical Readiness Test results of 100 active duty Navy personnel. Cholesterol levels were 200 mg/dl or greater in 42% of the subjects, with 32% having total:high-density lipoprotein cholesterol ratios of 5.0 or above. Additionally, HRA ages were significantly higher than chronological ages (p < or = .05). This study presents methods for (1) identifying needs for health teaching and/or counseling, and (2) increasing individual awareness of health risk factors and the effects of lifestyle on health risk.

Adult↗

Vascular ring: does magnetic resonance imaging replace angiography?

The records of 21 patients who underwent operation for symptoms attributable to vascular ring were reviewed. The study covered 33 years, 1958 to 1991, and the mean follow-up was 6.8 years. The patients ranged from 7 days to 26 years old with a mean age of 2.9 years. Twenty patients were symptomatic. Symptoms were due to tracheal compression in 16 patients, esophageal compression in 2, and both causes in 2. During the first 30 years, chest roentgenography, barium swallow, and aortography constituted the diagnostic workup in the majority of the patients. During the last 3 years, magnetic resonance imaging replaced aortography. The surgical diagnosis included five variants of vascular ring. The surgical approach consisted of left thoracotomy in 19 patients and right thoracotomy in 2. These 2 had the diagnosis of right aortic arch with posterior left subclavian artery. In both instances, preoperative angiographic data determined the surgical approach. Barium swallow may be sufficient for the diagnosis of vascular ring; however, additional data are useful in determining the surgical approach. Magnetic resonance imaging can yield accurate data without subjecting the patient to the risks associated with angiography.

Adolescent↗

Management of catastrophic neonatal midgut volvulus with a silo and second-look laparotomy.

The case of a neonate with midgut volvulus and severe intestinal ischemia extending from the ligament of Treitz to the midtransverse colon is presented. Management consisted of abdominal silo application at the initial exploration to obviate the adverse physiological consequences of increased intraabdominal pressure from reperfusion edema of the intestine. The majority of the intestine was salvaged, and a short segment of ileum was resected. This method of treatment resulted in optimal ventilatory status, renal function, and cardiac performance. The advantages of temporary prosthetic wound coverage in selected cases of midgut volvulus include greater physiologic stability through the avoidance of "intraabdominal hypertension" and the ability to monitor the status of the intestine at the bedside.

Duodenal Obstruction↗

Crocodilian evolution: insights from immunological data.

The quantitative immunological technique of microcomplement fixation was used to examine serum albumin evolution among members of the order Crocodylia. The cross-reactivity of the albumin antisera and antigens employed in this study had been examined previously using the qualitative technique of immunodiffusion. The phylogenetic conclusions derived from these two data sets are highly congruent, including support of the families Alligatoridae and Crocodylidae, with the placement of Gavialis as the sister taxon of Tomistoma. Both methods provide similar information on the relative amounts of amino acid sequence divergence between albumin molecules; however, the data obtained from microcomplement fixation comparisons are more discriminating than those derived from immunodiffusion. The estimated divergence times within the Crocodylia derived from the fossil record are examined in light of divergence times predicted by the microcomplement fixation-based albumin clock. The traditional phylogenetic placement of Gavialis outside the remaining extant crocodilians is inconsistent with all molecular data sets and we suggest that a careful reexamination of both the extant and the fossil morphological data is warranted.

Alligators and Crocodiles↗

Sequence and structural elements that contribute to efficient encephalomyocarditis virus RNA translation.

The nucleotide sequence of the 5' nontranslated region of encephalomyocarditis virus (EMCV-Rueckert) was determined, and a consensus RNA structural model for this sequence (850 bases) and three other poly(C)-containing cardioviruses (mengovirus, EMCV-B, and EMCV-D) was created through reiterative use of a minimum-free-energy folding algorithm. The RNA elements within this region which contribute to translation of EMCV proteins were mapped in cell-free reactions programmed with cDNA-derived RNA transcripts. The data provide evidence that stem-loop motifs I, J and K, formed by viral bases 451 to 785, are important components of cap-independent translation. In contrast to other reports, a minimal role for stem-loop H (bases 406 to 444) in translational activity is indicated. Small 5' nontranslated region fragments (bases 667 to 797) containing the J and K motifs proved strong competitive inhibitors when added to cell-free reactions programmed with exogenous capped or uncapped mRNAs. The putative sequestering of required translational factors by this segment clearly contributes to translational activity, but also suggests a possible competitive mechanism for the down regulation of host protein synthesis during viral infection.

Amino Acid Sequence↗

Sutureless hemisplenectomy.

Splenic salvage following blunt injury can fail when parenchymal bleeding is uncontrollable. To define the usefulness of an argon beam coagulator for hemostasis, we used the instrument in a laboratory trial of partial splenic resection. New Zealand white rabbits, weighing 4 to 5 kg, had sharp excision of the lower half of the spleen. No sutures were used to control hemorrhage from the cut splenic surface or the hilar vessels. Hemostasis was achieved with 2 to 4 seconds of electrocoagulation delivered by a beam of argon gas. All animals survived the procedure and were in good health when killed between the fourth and sixth week following the procedure. At necropsy, the spleen was viable in all animals with no abscess or hematoma. Minimal adhesions from the treated splenic surface to the omentum were found. The scar at the cut surface was 1 mm in depth, and the histology of the remainder of the spleen was normal. In this simulated splenic injury model, argon beam coagulation was uniformly successful in achieving hemostasis. Minimal tissue destruction and lack of infection were noted. The argon beam coagulator may be useful in patients with severe splenic injuries and other situations requiring partial splenectomy.

Animals↗

Laryngotracheal separation and diversion for complicated esophageal atresia with intractable salivary aspiration.

Chronic salivary aspiration results in progressive pulmonary deterioration. Laryngotracheal separation and diversion were performed to prevent salivary aspiration in a patient following complex repair for esophageal atresia with distal tracheoesophageal fistula. This highly effective and potentially reversible procedure should be considered for treatment of chronic salivary aspiration in selected patients.

Anastomosis, Surgical↗

Operative strategy for recurrent laryngeal cleft: a case report and review of the literature.

A case is reported of recurrent laryngotracheoesophageal cleft following two attempted repairs. The anterior approach to the larynx and trachea provided excellent exposure for defining the extent of the recurrent cleft, and allowed precise anatomic repair. Neurovascular structures were easily avoided by this operative method. Of 170 clefts reported in the literature, 19 recurred necessitating reoperation. The anterior approach to the larynx and trachea is appropriate in recurrent clefts and may be preferable at the initial repair.

Abnormalities, Multiple↗

Liver transplantation with calcific sclerosis of the portal vein.

Thrombosis or phlebosclerosis of the portal vein is an infrequent finding during the preoperative evaluation of a potential liver transplant recipient. Occasionally the process extends proximally into the superior mesenteric vein. This precludes conventional methods of portal venous reconstruction, necessitating reconstitution of portal venous inflow during liver transplantation through a venous conduit. The authors present a case of calcific phlebosclerosis of the portal and distal superior mesenteric veins that was delineated during preoperative imaging. This case emphasizes the importance of visualizing both the portal and superior mesenteric veins during the preoperative assessment, when patency of the portal vein is questionable. When the obliterative process extends into the distal superior mesenteric vein the authors recommend construction of the venous conduit from the proximal superior mesenteric vein as a pre-emptive manoeuvre before dissection of the recipient's liver and hilar structures. The venous conduit is then ready for immediate use during engraftment, thereby maintaining the shortest possible anhepatic time.

Calcinosis↗

Cyclic neutropenia with colonic perforation and nonhealing colocutaneous fistula.

Cyclic neutropenia is an hereditary disorder of white blood cells, characterized by profound neutropenic episodes approximately every three weeks. Septic complications are usually limited to cutaneous and oropharyngeal infections. A 4-year-old boy with known cyclic neutropenia was in shock with neutropenia, clostridial septicemia, and right lower quadrant peritonitis when he was admitted. At the time of laparotomy, inflammation of the cecum, with no gross perforation, was found; no resection or appendectomy was done. He subsequently developed a right lower quadrant abscess that was drained, resulting in a colocutaneous fistula. For the next 8 months his fistula persisted, with intermittent episodes of fever, increased fistula output, and abdominal pain during his neutropenic periods. Standard nonoperative approaches to healing the fistula failed (ie, elemental feeds, total parenteral nutrition, irrigations, antibiotics, and drains). Attempts to medically abolish his neutropenic episodes using lithium, gammaglobulin, and steroids also failed. Ultimately, he underwent an ileocecal resection with primary anastamosis; the operation was done immediately following a neutropenic episode, in order to allow adequate healing of his anastamosis before his next period of neutropenia. Postoperative course was satisfactory, and he remains well after 8 months follow-up. This case, and several similar previously reported cases, illustrate that cyclic neutropenia may present with serious surgical complications. They also underlines the important role that neutrophils play in the healing of enteric fistulae.

Agranulocytosis↗