DNA-PK and ATM drive phosphorylation signatures that antagonistically regulate cytokine responses to herpesvirus infection or DNA damage

The DNA-dependent protein kinase, DNA-PK, is an essential regulator of DNA damage repair. DNA-PK-driven phosphorylation events and the activated DNA damage response (DDR) pathways are also components of antiviral intrinsic and innate immune responses. Yet, it is not clear whether and how the DNA-PK response differs between these two forms of nucleic acid stress-DNA damage and DNA virus infection. Here, we define DNA-PK substrates and the signature cellular phosphoproteome response to DNA damage or infection with the nuclear-replicating DNA herpesvirus, HSV-1. We establish that DNA-PK negatively regulates the ataxia-telangiectasia-mutated (ATM) DDR kinase during viral infection. In turn, ATM blocks the binding of DNA-PK and the nuclear DNA sensor IFI16 to viral DNA, thereby inhibiting cytokine responses. However, following DNA damage, DNA-PK enhances ATM activity, which is required for IFN-β expression. These findings demonstrate that the DDR autoregulates cytokine expression through the opposing modulation of DDR kinases.

The Blood Proteoform Atlas: A reference map of proteoforms in human hematopoietic cells

Human biology is tightly linked to proteins, yet most measurements do not precisely determine alternatively spliced sequences or posttranslational modifications. Here, we present the primary structures of ~30,000 unique proteoforms, nearly 10 times more than in previous studies, expressed from 1690 human genes across 21 cell types and plasma from human blood and bone marrow. The results, compiled in the Blood Proteoform Atlas (BPA), indicate that proteoforms better describe protein-level biology and are more specific indicators of differentiation than their corresponding proteins, which are more broadly expressed across cell types. We demonstrate the potential for clinical application, by interrogating the BPA in the context of liver transplantation and identifying cell and proteoform signatures that distinguish normal graft function from acute rejection and other causes of graft dysfunction.

Cardiac proteomics reveals sex chromosome-dependent differences between males and females that arise prior to gonad formation

Sex disparities in cardiac homeostasis and heart disease are well documented, with differences attributed to actions of sex hormones. However, studies have indicated sex chromosomes act outside of the gonads to function without mediation by gonadal hormones. Here, we performed transcriptional and proteomics profiling to define differences between male and female mouse hearts. We demonstrate, contrary to current dogma, cardiac sex disparities are controlled not only by sex hormones but also through a sex-chromosome mechanism. Using Turner syndrome (XO) and Klinefelter (XXY) models, we find the sex-chromosome pathway is established by X-linked gene dosage. We demonstrate cardiac sex disparities occur at the earliest stages of heart formation, a period before gonad formation. Using these datasets, we identify and define a role for alpha-1B-glycoprotein (A1BG), showing loss of A1BG leads to cardiac defects in females, but not males. These studies provide resources for studying sex-biased cardiac disease states.

Systematic profiling of protein complex dynamics reveals DNA-PK phosphorylation of IFI16 en route to herpesvirus immunity

Dynamically shifting protein-protein interactions (PPIs) regulate cellular responses to viruses and the resulting immune signaling. Here, we use thermal proximity coaggregation (TPCA) mass spectrometry to characterize the on-off behavior of PPIs during infection with herpes simplex virus 1 (HSV-1), a virus with an ancient history of coevolution with hosts. Advancing the TPCA analysis to infer associations de novo, we build a time-resolved portrait of thousands of host-host, virus-host, and virus-virus PPIs. We demonstrate that, early in infection, the DNA sensor IFI16 recruits the active DNA damage response kinase, DNA-dependent protein kinase (DNA-PK), to incoming viral DNA at the nuclear periphery. We establish IFI16 T149 as a substrate of DNA-PK upon viral infection or DNA damage. This phosphorylation promotes IFI16-driven cytokine responses. Together, we characterize the global dynamics of PPIs during HSV-1 infection, uncovering the co-regulation of IFI16 and DNA-PK functions as a missing link in immunity to herpesvirus infection.

Lamin B1 acetylation slows the G1 to S cell cycle transition through inhibition of DNA repair

The integrity and regulation of the nuclear lamina is essential for nuclear organization and chromatin stability, with its dysregulation being linked to laminopathy diseases and cancer. Although numerous posttranslational modifications have been identified on lamins, few have been ascribed a regulatory function. Here, we establish that lamin B1 (LMNB1) acetylation at K134 is a molecular toggle that controls nuclear periphery stability, cell cycle progression, and DNA repair. LMNB1 acetylation prevents lamina disruption during herpesvirus type 1 (HSV-1) infection, thereby inhibiting virus production. We also demonstrate the broad impact of this site on laminar processes in uninfected cells. LMNB1 acetylation negatively regulates canonical nonhomologous end joining by impairing the recruitment of 53BP1 to damaged DNA. This defect causes a delay in DNA damage resolution and a persistent activation of the G1/S checkpoint. Altogether, we reveal LMNB1 acetylation as a mechanism for controlling DNA repair pathway choice and stabilizing the nuclear periphery.

Oncogenic KRAS and BRAF Drive Metabolic Reprogramming in Colorectal Cancer

Metabolic reprogramming, in which altered utilization of glucose and glutamine supports rapid growth, is a hallmark of most cancers. Mutations in the oncogenes KRAS and BRAF drive metabolic reprogramming through enhanced glucose uptake, but the broader impact of these mutations on pathways of carbon metabolism is unknown. Global shotgun proteomic analysis of isogenic DLD-1 and RKO colon cancer cell lines expressing mutant and wild type KRAS or BRAF, respectively, failed to identify significant differences (at least 2-fold) in metabolic protein abundance. However, a multiplexed parallel reaction monitoring (PRM) strategy targeting 73 metabolic proteins identified significant protein abundance increases of 1.25-twofold in glycolysis, the nonoxidative pentose phosphate pathway, glutamine metabolism, and the phosphoserine biosynthetic pathway in cells with KRAS G13D mutations or BRAF V600E mutations. These alterations corresponded to mutant KRAS and BRAF-dependent increases in glucose uptake and lactate production. Metabolic reprogramming and glucose conversion to lactate in RKO cells were proportional to levels of BRAF V600E protein. In DLD-1 cells, these effects were independent of the ratio of KRAS G13D to KRAS wild type protein. A study of 8 KRAS wild type and 8 KRAS mutant human colon tumors confirmed the association of increased expression of glycolytic and glutamine metabolic proteins with KRAS mutant status. Metabolic reprogramming is driven largely by modest (<2-fold) alterations in protein expression, which are not readily detected by the global profiling methods most commonly employed in proteomic studies. The results indicate the superiority of more precise, multiplexed, pathway-targeted analyses to study functional proteome systems. Data are available through MassIVE Accession MSV000079486 at ftp://MSV000079486@massive.ucsd.edu.

The effect of diet on the bearing mucosa during adjustment to new complete dentures: a pilot study

PURPOSE

This pilot study investigated the reliability of the conventional prosthodontic wisdom that a modified diet ameliorates soreness during the adjustment to new complete dentures. Tissue ulceration of the bearing mucosa served as the indicator of patient soreness as a function of diet.

MATERIAL AND METHODS

Fourteen men were randomly assigned to two equal treatment groups. One group consumed a consistency-gradated diet and the other (control) ate as they wished. New complete dentures were fabricated for both groups by the same provider, technician, materials, and method; the study was double-blinded. Tissue ulceration was assessed and totaled for the 10 days after denture placement, constituting a soreness score.

RESULTS

Data analysis identified a significant difference in soreness scores between dietary groups (p < 0.05). Wearing time had a significant inverse relation to soreness (p < 0.05) in this study. A host of potential explanatory variables of clinical interest failed to relate significantly to the outcome of soreness.

CONCLUSIONS

The results of this study indicated that a consistency-gradated diet had a significant effect in diminishing tissue ulceration during the immediate postplacement period for this group of men. Potentially, these findings could contribute to enhanced quality of care and to the more efficient allocation of provider-based resources.

Bond strengths of the adhesive resin-amalgam interface

PURPOSE

To evaluate the tensile and shear bond strengths of eight adhesives and two amalgams (spherical and lathe cut).

MATERIALS AND METHODS

Two high-copper amalgams (Tytin, spherical; and ANA-2000, dispersed phase) and seven adhesives (Panavia EX, C&B Metabond, Chameleon Metal Resin Cement, All-Bond 2, All-Bond C&B, Photo-Bond and Imperva Dual) were evaluated. An epoxy resin (Stycast 1266) was included as a control for comparison because it was an adhesive material of similar viscosity but different chemistry from the dental adhesives. The aluminum surfaces were sandblasted with 50 microns aluminum oxide just prior to coating with adhesive resins. The testing area was defined with a 4 mm circular adhesive Mylar mask. All adhesives were mixed and handled according to manufacturers' instructions. Freshly mixed amalgam was condensed into the test cavity and onto the surface immediately after coating with adhesive. After 24 hours storage, the bond strengths were determined in an Instron testing machine at a crosshead speed of 2 mm/minute. The debonded surfaces were examined in an optical microscope for site of failure. The few samples which showed failure at the aluminum-resin interface were not included in the study. Selected debonded surfaces were examined by SEM. A 2-way ANOVA (General Levin Models-GLM) was used to analyze the data from both the tensile and shear bond strength tests. GLM was used instead of standard ANOVA because of the unbalanced design. The lack of balance occurred because some of the bonding resin/amalgam groups had different sample numbers.

RESULTS

A wide variation in bond strengths was obtained with adhesive resin cements and not all appeared suitable for adhesive amalgam restorations. Panavia EX, C&B Metabond, Chameleon Metal Resin Cement and All-Bond C&B showed the best potential for amalgam bonding, with shear and tensile bond strengths greater than 8 MPa. Viscous, filled versions of adhesives appeared to be more effective. Choice of amalgam appeared to be less important than choice of adhesive.

Prosthodontic treatment, patient response, and the need for maintenance of complete implant-supported overdentures: an appraisal of 5 years of prospective study

The prosthodontic methods and outcomes of treating 127 patients in nine centres over a period of 5 years is described. The benefits perceived by patients and the changes induced in the denture-bearing tissues and temporomandibular joints are reported. To sustain effective treatment outcomes, the levels of maintenance needed by the overdentures are contrasted for restoration of the edentulous mandibles and maxillae.

In vitro enamel demineralization and the marginal gap of simulated cast restorations with three different cements

PURPOSE

This study investigated 1) the relationship between marginal gap sizes and enamel demineralization, and 2) the influence of three cements on this enamel demineralization.

MATERIALS AND METHODS

Horizontal sections of 60 noncarious, freshly extracted human third molars were randomly assigned to one of four groups. Simulated cast restorations were attached to the specimens with 1) zinc phosphate cement, 2) glass ionomer cement, 3) composite resin cement, or 4) no cement (control). The tooth/restoration gaps were controlled at 51, 102, and 204 microns. The specimens were incubated for 16 weeks in buffered lactic acid gelatin to induce demineralization. Photomicrographs were obtained from sections of each sample using a polarized light microscope. Three evaluators measured wall and primary enamel lesion depths allowing for the determination of a demineralization ratio (DR). Data were analyzed by repeated-measures ANOVA (alpha = 0.05).

RESULTS

The between-evaluator effects were not significant. All evaluators agreed that DR was significantly related to cement (p = .0001) but not to marginal gap size. The resin cement had the smallest DR (0.7 +/- 0.3), and the control group had the greatest (4.4 +/- 2.0).

CONCLUSIONS

The presence of any one of the three investigated cements resulted in decreased demineralization. The amount of demineralization was unaffected by marginal gap size.

A 5-year prospective multicenter follow-up report on overdentures supported by osseointegrated implants

This report presents the results of a 5-year prospective multicenter study including nine centers worldwide. A total of 30 patients received 117 Brånemark implants in the maxillae, and 103 patients received 393 implants in the mandibles. According to the protocol, all integrated maxillary implants were to be loaded; however, only two of four mandibular implants were planned for support of the overdentures, leaving the remaining implants covered by mucosa as backup for possible implant failures. Thirty-five patients (26.3%) who were provided with 127 implants (24.9%) were withdrawn from the study. Six patients treated in the maxilla lost all their implants and resumed wearing complete dentures. The cumulative success rates for implants and for overdentures supported by two implants in the edentulous mandible were 94.5% and 100%, respectively. The corresponding cumulative success rates for implants and for overdentures supported by an optimal number of implants in the maxilla were 72.4% and 77.9%, respectively. Significantly better jawbone characteristics at the time of implant surgery were considered to contribute to the better cumulative success rates in the mandibles. Mean marginal bone loss was 0.8 mm (SD 0.8) and 0.5 mm (SD 0.8) for loaded implants during a 5-year period of time in the maxillae and mandibles, respectively. Measurements of the clinical height of the abutment cylinders indicated a mean recession (0.2 mm) of peri-implant mucosa during the follow-up period in the mandibles. Conversely, hyperplasia was observed in the maxillae.

An assessment of the association between functional edentulism, obesity, and NIDDM

OBJECTIVE

To assess the association between a measure of extensive tooth loss (functional edentulism) and obesity with non-insulin-dependent diabetes mellitus (NIDDM) in a racially heterogeneous sample.

RESEARCH DESIGN AND METHODS

A cross-sectional survey (370 subjects) was performed by reviewing the medical and dental records of dependently or independently living individuals who were treated as inpatients and/or outpatients at a Department of Veterans Affairs facility. Frequencies and descriptive measures were derived; univariate and multiple logistic regression analyses were conducted to test for associations, confounding, effect modification, and interaction using functional edentulism and obesity as the independent variables and NIDDM as the dependent measure.

RESULTS

Functionally edentulous individuals were at significantly greater risk for NIDDM (estimated odds ratio [OR] = 4.06), than the obese (OR = 3.29). These relationships were not confounded by age or race in this sample. Obesity did confound functional edentulism in the multivariable model, suggesting that they act independently on the outcome variable (NIDDM).

CONCLUSIONS

Dentist-assessed functional edentulism and physician-diagnosed obesity were significantly associated with NIDDM in this sample of predominantly older men. This finding ought to be considered by primary care providers in formulating dietary strategies in order to facilitate the realization of their therapeutic goals.

Expansion of phosphate-bonded investments: Part II--Thermal expansion

This study investigated the thermal expansion of phosphate-bonded investment materials. Three investments were mixed with either distilled water or their special liquids and allowed a setting time of 1 or 24 hours. Hydration and thermal expansions were measured with a vertical dilatometer and were analyzed for interactive and main effects. The amount of expansion attributed to hydration was minimal, whereas thermal expansions varied and were of greater magnitudes. Material I exhibited the greatest thermal expansion. Materials II and III recorded smaller thermal expansions that increased when the materials were mixed with their special liquids. Setting time did not substantially influence hydration expansions but did influence thermal expansions, and heating the materials to 800 degrees C instead of 700 degrees C did not dramatically elevate expansions.

Factors related to success and failure rates at 3-year follow-up in a multicenter study of overdentures supported by Brånemark implants

An international prospective study of Brånemark implants retaining overdentures was conducted at nine clinical centers. One hundred thirty-three subjects were recruited in a 12-month period and provided with 510 implants, 117 of which were in maxillae and 393 were in mandibles. This study reports the 3-year follow-up status of 120 overdentures and 444 implants. There were 11 overdenture failures (9.2%). Maxillary overdenture failure rates (27.6%) were nearly nine times greater than mandibular overdenture failure rates (3.3%). Maxillary overdenture treatment was less successful than previously reported fixed implant-supported restorations. However, their mandibular counterparts had success rates slightly higher than those reported for fixed implant-supported restorations. At 3 years, 150 implants remained submerged and 66 implants had been withdrawn because the subjects discontinued study participation. Eleven mandibular and 29 maxillary implants had failed and had been removed from 21 subjects. Logistic regression with forward model selection indicated that one two-way interaction was significantly related to implant failure. At highest risk were the subjects who possessed dental arches with bone quantity E and bone quality 4. Subjects with one implant failure were likely to have more than one failure. The Generalized Estimating Equation was used to adjust for the cluster effect in this population because multiple implants (2 to 6) were placed and evaluated in each of the 133 subjects.

The expansion of phosphate bonded investments: Part I--Setting expansion

Less expensive silver and palladium (AgPd) dental casting alloys are popular, but require phosphate bonded investments. The physical properties of such materials have not been thoroughly investigated. This study determined whether three different phosphate bonded investments could provide adequate expansion to compensate for the casting shrinkage of AgPd. The investments were mixed with distilled water or their unique special liquids provided by the manufacturers and allowed setting times of 1 hour or 24 hours. Setting expansions were measured with a vertical dilatometer. When mixed with special liquid, material I had a mean setting (1 hour) expansion of 0.19% +/- 0.01%; material II, 0.14% +/- 0.03%; and material III, 1.17% +/- 0.08%. Twenty-four hours of setting did not significantly increase the setting expansion (p > 0.05). Mixing the three investments with distilled water drastically reduced setting expansions. A three-way analysis of variance was computed to evaluate the data and investigate significant interactive and main effects. The two-way interaction (material x liquid) was significant. The results were consistent with the concept of a higher silica-containing special liquid for material III compared with the other materials.

Axiographic tracings of temporomandibular joint movements

Three-dimensional condylar movements of 49 symptomatic and asymptomatic volunteers were recorded with a hinge axis tracing system axiograph during maximal opening, protrusion, and mediotrusion. The tracings displayed in sagittal and frontal planes were measured to evaluate biomechanics of the temporomandibular joint. The only differences in condylar tracings between symptomatic and asymptomatic groups were in the right joint, recorded in the sagittal plane during maximal opening, and the Bennett angle. The symptomatic group had a significantly longer condylar path and a smaller Bennett angle compared with the asymptomatic group. The results were interpreted as indications of adaptive morphologic instead of pathologic changes. The alterations in condylar tracings as an indicator of joint pathology should be considered cautiously.

Clinical spectrum of symptomatic external iliac fibromuscular dysplasia

External iliac fibromuscular dysplasia is a rare and usually asymptomatic disorder. We report eight symptomatic patients seen over a 15-year period and review pathophysiologic mechanisms accounting for the three following distinct lower extremity ischemic sequelae: (1) Emboli--episodic focal digital ischemia (blue toe) was seen in three patients. Resection and primary anastomosis of focal iliac ulcerative fibromuscular dysplasia (one patient) or resection and replacement (two patients) removed the embolic source and relieved the symptoms. (2) Chronic ischemia--gradual onset of full leg claudication in four patients was treated by operative graduated intraluminal dilation in three patients and prosthetic bypass in one. Arteriography subsequently showed a remodeled lumen in the three patients who underwent dilation. (3) Dissection--acute onset leg ischemia resulted from presumed dissection of the external iliac segment. After 4 months of conservative management of antiplatelet agents and exercise, symptoms resolved completely, and arteriogram showed spontaneous restoration of a normal lumen in the dissected segment. The clinical presentation of fibromuscular dysplasia may mimic other arterial processes such as atherosclerosis. Diagnosis is made only by arteriography with specific magnification views of the external iliac arteries and careful surveillance of the renal arteries. Appropriate treatment should be tailored to the clinical presenting symptom. For microembolic disease, resection and replacement are required. For chronic ischemia, intraluminal dilation is generally sufficient and durable and has proved to be a simpler and acceptable alternative to replacement or bypass. In acute dissection, surgical intervention may be deferred if the limb is viable to allow spontaneous healing and remodeling. Persistent symptoms may be the only indication for intervention in this ischemic manifestation of external iliac fibromuscular dysplasia.

Evaluation of the effects of palatal augmentation on partial glossectomy speech

Patients who have had surgical removal of part of the tongue are left with varying degrees of speech deficiencies. Augmentation of the palate has been suggested as a means of compensation for this deficiency. This pilot study suggests a technique for evaluating prosthodontic efforts to improve speech for partial glossectomy patients. Although firm conclusions cannot be based on the observations of one patient, it appears that both the shape of the palatal surface and the contour of the cavity size anterior to the tongue are important factors to be considered in prosthodontic efforts to optimize fricative sound production for partial glossectomy patients. Further studies with patients who have a wider variety of tongue resections are indicated. The technique described is an effective one for further studies.

Percutaneous transluminal balloon angioplasty of the iliac artery for contralateral ischemia

The cases of three patients with lower extremity ischemia from ipsilateral iliac artery occlusion and contralateral iliac artery stenosis are presented. Planned treatment was percutaneous transluminal angioplasty (PTA) of the contralateral iliac artery, rendering it an adequate donor vessel for subsequent femorofemoral bypass. Because of adequate collateral vessels across the pelvis, cross-femoral bypass was unnecessary following PTA. Current technology allows simultaneous intraoperative PTA and femorofemoral bypass. We do not recommend this on the basis of our experience.

Etiologic factors for recurrent carotid artery stenosis

Since 1966, 29 patients with recurrent carotid artery stenosis have been encountered. The mean (+/- SEM) internal between initial carotid endarterectomy and secondary presentation was 67.5 +/- 9.2 months (range 6 to 180 months). There was a disproportionate number of women with recurrent stenosis. The mean age at initial endarterectomy in patients with recurrent stenosis, 54.6 +/- 1.4 years, was significantly less (P less than 0.001) than that of all patients who had endarterectomy. To define the etiologic factors for recurrence, 21 of these patients were matched with case-control patients of the same age and sex who had undergone endarterectomy the same year but did not develop recognized recurrent stenosis. There was no significant difference in the incidence of hypertension, diabetes mellitus, coronary artery disease, bilateral carotid disease, other vascular operations, or family history for atherosclerosis in patients with recurrent stenosis compared to control patients. The indications for primary endarterectomy, angiographic distribution of disease, and operative details were similar in both groups. There was no difference in the incidence of regular, therapeutic aspirin ingestion following initial endarterectomy (52.5% in both groups). There was a striking difference in smoking habits. Ninety-five percent of patients with recurrent stenosis continued to smoke following initial endarterectomy, compared to 23.8% of control patients (P less than 0.001). Lipid fractionation studies were performed in both groups, and there were no significant differences in levels of cholesterol, triglycerides, high-density lipoprotein (HDL)-cholesterol, and total cholesterol/HDL-cholesterol ratio. Dose-response platelet aggregometry detected no differences between groups in the sensitivity of platelets to adenosine diphosphate (ADP), collagen, and epinephrine. Reoperation in patients with recurrent stenosis was associated with minimal morbidity, no deaths, and generally excellent results.

Dilation of knitted Dacron aortic prostheses and anastomotic false aneurysms: etiologic considerations

Five patients with knitted Dacron aortic bifurcation prostheses developed prosthetic dilation and anastomotic false aneurysms. The interval between placement of prostheses and secondary presentation ranged from 4 to 10 years. Three patients presented with femoral false aneurysms (one ruptured) and two presented with aortic false aneurysms (one ruptured). In all cases, anastomotic sutures remained intact on the prosthesis and there was no evidence of infection. The mean (+/- SEM) increase in diameter of prostheses was 85.7 +/- 19.1% (range 76% to 137%). Dilated prostheses were removed in four cases and were tested for tensile strength and studied with scanning electron microscopy. These were compared to normal, nondilated knitted Dacron prosthetic fabric from the same manufacturer. There was no loss of breaking strength in dilated prostheses. Furthermore, on examination with scanning electron microscopy, there was no evidence of degeneration or fracturing of individual Dacron filaments. However, dilated prostheses were found to have a greatly expanded knit. The distance between loops was significantly increased and the number of fibers per 1000 microns was significantly less in comparison to normal knitted Dacron fabric. These studies confirm an association between prosthetic dilation and false aneurysm formation. Further, they suggest that the cause of prosthetic dilation is loss of compactness of the knit not associated with intrinsic Dacron fiber deterioration. A fabrication defect is most likely responsible.

A comparison of three techniques for fabricating metal molds

Investigation on the dimensional accuracy and techniques variability of metal molds and refractory casts for the construction of maxillofacial external prostheses have resulted in the following conclusions. 1. A relative comparison of the box-pour, open-cast, and wax-sprue techniques for constructing metal molds for external prostheses showed the open-cast technique to be the most accurate and easiest techniques. 2. The wax-sprue technique was the most complex and consumed maximum time and materials. This technique also offered the greatest possibility for introducing errors and obtaining inconsistent results because of multiple steps. 3. For all techniques the positive metal molds always demonstrated a poorer fit in comparison to the negative metal molds. The positive metal molds were larger castings. 4. Most metal molds were significantly larger than the standard brass die in length and width dimensions. 5. A direct comparison of a theoretic calculation and experimental measurements for dimensional accuracy shows the construction of metal molds to be very dependent on the manipulation of materials and reproducibility of methods.

Injuries sustained from high velocity impact with water: an experience from the Golden Gate Bridge

Over 720 persons are reported to have died jumping from the Golden Gate Bridge. A review of 100 consecutive autopsies showed that, in the majority of cases, massive pulmonary contusion, pneumothorax, laceration or perforation of the heart, great vessels, or lungs by displaced ribs were the causes of immediate death. Irreparable fractures of the liver or spleen were the most common abdominal injuries. The persons fatally injured appeared to have entered the water in a horizontal position, experiencing maximal deceleration. In contrast, six survivors entered the water feet first with more gradual deceleration. These survivors remained conscious but sustained similar injuries of lesser degree; only one sustained rib fractures. Fifty per cent had fractures of the liver or spleen requiring operative therapy. Fifty per cent sustained lung contusions and subsequent pneumothoraces. Suspicion of underlying injuries to the liver, spleen, and lungs is essential during resuscitation of those who survive impact with water.

Perforated jejunal diverticulitis

The 25th case of perforated jejunal diverticulitis is reported and all previous cases are reviewed. The mortality in this group of patients is 32%. Resection of the perforated segment with end-to-end anastomosis seems to offer the best chance of cure.