Disentangling the effect of growth from development in size-related trait scaling relationships

In plant ecology, the terms growth and development are often used interchangeably. Yet these constitute two distinct processes. Plant architectural traits (e.g. number of successive forks) can estimate development stages. Here, we show the importance of including the effect of development stages to better understand size-related trait scaling relationships (i.e. between height and stem diameter). We focused on one common savanna woody species (Senegalia nigrescens) from the Greater Kruger Area, South Africa. We sampled 406 individuals that experience different exposure to herbivory, from which we collected four traits: plant height, basal stem diameter, number of successive forks (proxy for development stage), and resprouting. We analysed trait relationships (using standardized major axis regression) between height and stem diameter, accounting for the effect of ontogeny, exposure to herbivory, and resprouting. The number of successive forks affects the scaling relationship between height and stem diameter, with the slope and strength of the relationship declining in more developed individuals. Herbivory exposure and resprouting do not affect the overall height-diameter relationship. However, when height and stem diameter were regressed separately against number of successive forks, herbivory exposure and resprouting had an effect. For example, resprouting individuals allocate more biomass to both primary and secondary growth than non-resprouting plants in more disturbed conditions. We stress the need to include traits related to ontogeny so as to disentangle the effect of biomass allocation to primary and secondary growth from that of development in plant functional relationships.

Single-row versus transosseous technique in the arthroscopic treatment of rotator cuff tears: a meta-analysis

PURPOSE

This study aims to compare single-row suture-anchors (SA) versus transosseous arthroscopic (TO) technique in the treatment of patients with rotator cuff tears in terms of clinical structural outcomes at atleast 24 months of follow-up.

METHODS

The systematic review was performed according to "PRISMA guidelines" (Preferred Reporting Items for Systematic Reviews and Meta-analyses), in order to identify all the studies comparing clinical, both subjective and objective, outcomes with 24 months follow-up minimum in patients undergoing arthroscopic RC repair with the SR and TO technique. OVID-MEDLINE®, Cochrane, SCOPUS and PubMed were searched from January 2010 to October 2022 to identify relevant studies, using the following key words, that were combined together to achieve maximum search strategy sensitivity: "Rotator cuff tear" OR "repair" OR "shoulder" OR "reconstruction" OR "suture" OR "arthroscopic" OR "single-row" OR "transosseous".

RESULTS

Six papers were finally analyzed in this meta-analysis. The weighted mean difference on Constant scores and for ASES for studies considering suture-anchors (SA) group showed good outcomes. The weighted mean difference of Constant scores and of ASES for TO (transosseous) group showed good outcomes. The weighted mean difference of CONSTANT for TO versus SA groups showed no differences in the outcomes of SA and TO techniques for the repair of Rotator Cuff Tears at minimum 24 months follow-up.

CONCLUSIONS

The Arthroscopic transosseous rotator cuff repair technique and SA (suture-anchor) technique both lead to significant short-term improvement and satisfactory subjective outcome scores with low complication/failure rates. No differences were found in the final outcome between the two techniques.

Atypical Vancouver B1 Periprosthetic Fractures: The Unsolved Problem

Atypical femoral fractures (AFF) are stress or insufficiency fractures induced by low energy trauma or no trauma, frequently correlated with prolonged bisphosphonate therapy. The diagnosis follows major and minor criteria, originally described by the Task Force of the American Society for Bone and Mineral Research in 2010 and updated in 2014. However, the definition of AFFs in the report excluded periprosthetic fractures. When atypical fractures occur close to a prosthetic implant the situation become critical, the surgical treatment is often demolitive and supported by medical treatment. Moreover, acute ORIF as a first line treatment is frequently burdened by a high failure rate , and often a stem revision is required as second line treatment. The healing process is long and difficult with poor functional results and impairing outcomes. We present a case treated at our institution of a 78 year old woman with a history of a femoral atypical periprosthetic fracture, complicated by multiple surgical revisions. Its arduous management reflects all the difficulties that these type of fractures could present to the surgeon, while its good final result may teach us how to approach them in a correct way.

Choice of treatments of the coronal shear fractures of the humerus. A national survey of Italian AO members

INTRODUCTION

Coronal shear fractures of the distal humerus are uncommon injuries representing 6% of distal humeral fractures. There is no univocal consensus about the correct management of this type of fracture. A national survey was conducted to gain more insight into the current classification, diagnosis and treatment of coronal shear fractures in Italy.

MATERIALS AND METHODS

A postal survey was sent to all AO Italian members including residency orthopaedic surgeons. The survey consisted of general questions about personal experience in the management of these fractures: types of classification systems used, surgical approaches, treatment options and rehabilitation programs.

RESULTS

114 orthopaedic surgeons answered a 13-items questionnaire. The most used classification system was AO/OTA (72,8%). Independent screws and if necessary plates were the most answered regarding surgical treatment (81,6%). The most encountered post-surgical complication was stiffening of the elbow (81,6%).

CONCLUSION

An algorithm of treatment has been proposed. To better classify coronal shear fractures, the authors recommended the integration of two classification systems: AO and Dubberley classifications. In the case of posterior wall comminution, a Kocher extensile approach is recommended, otherwise, if a posterior wall is intact, Kocher or Kaplan approach can be used. The posterior transolecranic approach can be reserved to Dubberley type III or AO 13B3.3. The best treatment choice is represented by independent screws and plates placed according to fracture patterns while arthroplasty is indicated when a stable ORIF is not possible. Mobilization is postponed for about 2 weeks.

Is the Posterior Approach With Posterior locking compression plate and Anterior Allograft Useful and Safe in the Treatment of Periprosthetic Humeral Fractures Following Reverse Total Shoulder Arthroplasty?

Introduction

As the reverse total shoulder arthroplasty (RTSA) surgery has dramatically increased in the last few decades, many complications have followed through. The periprosthetic fracture, at the moment, is still a subject of debate in the orthopedic world. In this monocentric study, along with a literature review of periprosthetic humeral fractures, we would present our institutional experience with the treatment of periprosthetic humeral fractures with a posterior humeral approach, posterior cortex plate fixation, anterior strut allograft, screws, and cerclage wires.

Materials and Methods

Our study consisted in a prospective monocentric study based on 18 patients, with a mean age of 75.3 years (range 64–88), all following a reverse shoulder total arthroplasty (RTSA). Postoperative follow-ups were taken at 1, 6, and 12 months with objective measurement of shoulder motion and strength, while clinical outcome measures were assessed using the American Shoulder and Elbow Surgeons (ASES score) and visual analog scale (VAS) for pain. Together with that, we performed a literature review focused on the management of periprosthetic humeral fractures after shoulder arthroplasty.

Results

All fractures consolidated without complication at a mean 4.2 months (range 3–6). At final follow-up, the average active shoulder flexion was 88° (range 62–129°), active abduction 73° (range 52–91°) and active external rotation 22° (range 3–56°). The average ASES score was 73 (range 59–97), while average VAS score was 1.1 (range 0–3).

Discussion

Surgical treatment of periprosthetic humeral fractures following a shoulder arthroplasty remains a hard challenge for every surgeon, and their treatment must consider fracture’s location, displacement, and local bone quality.

Conclusions

The posterior approach with a posterior plate placement and anterior strut allograft, which is appliable only in case of a B or C type fracture according to Worland classification, could be a good treatment option for periprosthetic humeral fractures.

Use of the 95-degree angled blade plate with biological and mechanical augmentation to treat proximal femur non-unions: a case series

BACKGROUND

Intertrochanteric and subtrochanteric non-union are rare but challenging complications. In the present study, we investigate the use of a 95° blade, in association with biological and mechanical augmentation, in the management of intertrochanteric and subtrochanteric femoral non-unions.

METHODS

Between October 2015 and February 2021, a retrospective cohort study was conducted at our institution to investigate the use of a 95° blade, in association with biological and mechanical augmentation, in the management of intertrochanteric and subtrochanteric femoral non-unions, following the mechanical failure of the first device. All the patients underwent a clinical and radiographic follow-up at 6 weeks, 3, 6, 9, 12 and 18 months; at each follow-up, a plain radiograph of the femur was performed and patients were assessed using Harris Hip Score (HHS) and the Short Form-12 (SF-12) questionnaire.

RESULTS

From October 2015 and February 2021, 40 proximal femur non-unions were managed at our Institution. Fifteen patients out of forty (37.5%) met the inclusion criteria. The main data of the study are summarized in Table 1; patients' mean was 57 years old (range 19-83); 10 males and 5 females were included in the study. All the patients completely healed clinically and radiologically at an average of 6.1 months (range 4-13). All these patients returned to their pre-injury mobility status. During an average follow-up period of 25 months (range 8-60), the observed complications included wound dehiscence, which was treated with a superficial surgical debridement, a below-the-knee deep vein thrombosis, and a blade plate failure 3 months after the first revision surgery.

CONCLUSIONS

This study shows the treatment of inter-and sub-trochanteric non-unions with a 95° blade plate, medial strut allograft, and bone autograft obtained with RIA system, together with a varus malalignment correction, leads to a high percentage of bone healing, with a low incidence of complications and good clinical outcome.

A Newly Identified Complication of Patellofemoral Arthroplasty: Case Report and Literature Review

Background

Patellofemoral arthroplasty (PFA) is a surgical option for patients older than 40 years old who are affected by patellofemoral osteoarthritis. Regarding the complications of PFAs, few studies have investigated periprosthetic fractures. The purpose of this literature review was to highlight a previously overlooked complication of primary prosthetic surgery of the patellofemoral joint.

Methods

Three literature databases were searched for studies published between 2000 to 2020 using relevant keywords. A total of 4,942 articles were originally identified. After excluding duplicates and analysing the titles and abstracts, 20 studies were considered. From these, data regarding the number of cases, clinical outcomes and complications were extracted.

Results

Among the 20 selected articles, only one described periprosthetic fractures as a complication of PFAs. Herein, we also report an illustrative case of an unknown fracture complication. No cases in the literature were found that described the type of complications experienced by our patient during the postoperative period.

Conclusions

This review confirms the lack of data about clinical outcomes and fracture complications of PFAs. In primary prosthetic surgery of the patellofemoral joint, patient selection and close consideration of demographic factors (such as BMI and age) and intraoperative factors (such as patellar thickness and size of the trochlear component) play a key role in optimising pre-operative planning to avoid intraoperative periprosthetic fractures.

Modular neck stems in total hip arthroplasty: current concepts

Modular neck (MN) implants can restore the anatomy, especially in deformed hips such as sequelae of development dysplasia.

Early designs for MN implants had problems with neck fractures and adverse local tissue, so their use was restricted to limited indications.

Results of the latest generation of MN prostheses seem to demonstrate that these problems have been at least mitigated.

Given the results of the studies presented in this review, surgeons might consider MN total hip arthroplasty (THA) for a narrower patient selection when a complex reconstruction is required.

Long MN THA should be avoided in case of body mass index > 30, and should be used with extreme caution in association with high offset femoral necks with long or extra-long heads. Cr-Co necks should be abandoned, in favour of a titanium alloy connection.

Restoring the correct anatomic femoral offset remains a challenge in THA surgeries.

MN implants have been introduced to try to solve this problem. The MN design allows surgeons to choose the appropriate degree and length of the neck for desired stability and range of motion.

Cite this article: EFORT Open Rev 2021;6:751-758. DOI: 10.1302/2058-5241.6.200064

Intraspecific variability of specific leaf area fosters the persistence of understorey specialists across a light availability gradient

Forest understorey plants are sensitive to light availability, and different species groups can respond differently to changing light conditions. A plant trait tightly linked to light capture is specific leaf area (SLA). Studies considering the relative role of within- and among-species SLA variation across different species groups (e.g. specialists and generalists) are rarely implemented in temperate forest understories varying in their maturity. We examined community-level SLA patterns of beech forest understories along a light availability gradient, and for habitat specialists and generalists separately. We then disentangled and quantified the contribution of intraspecific trait variability and interspecific trait differences in shaping SLA patterns. We revealed that the increase in community-level SLA with decreasing light availability was primarily driven by beech forest specialists (and, to a lesser extent, by forest generalists), and this pattern was mainly determined by specialists' high intraspecific variability. Community-level SLA was therefore formed by different responses at different organizational levels, i.e. within and among species, and for separate species groups. This study provides insights into factors shaping the shade tolerance strategy in beech forest understorey plants; specialists persistence under putative less favourable conditions (i.e. high irradiation) may be fostered by their ability to adjust their light capture strategies intraspecifically.

The role of biophysical stimulation with pemfs in fracture healing: from bench to bedside

Clinical biophysics investigates the relationship between non-ionizing physical energy and the human body. This narrative review aims to summarize the current evidence on the efficacy of PEMF-therapy in the promotion of fracture healing. The effectiveness of PEMFs has been deeply investigated in preclinical in vitro ed in vivo studies and level-I clinical studies. All these studies depicted only PEMF-devices with specific physical wave features - i.e. pulse shape, frequency and amplitude- could significantly promote bone repair. Moreover, the dose-response relationship was also defined in preclinical studies, thus providing the minimum exposure time needed in PEMF-therapy. PEMFs are currently employed in the management several bone injuries, including acute fractures at non-union risk, non-unions, osteotomies, stress fractures and osteonecrosis. Moreover, several ongoing studies are investigating the effectiveness of PEMFs on emerging clinical conditions, thus the indications to PEMF-therapy could potentially raise in future years.

Minimally invasive osteosynthesis technique in the treatment of transverse patellar fractures in the elderly

BACKGROUND

This prospective study aims to describe our experience in the management of transverse patellar fractures in elderly patients with minimally invasive osteosynthesis technique (MIOT), at 12-months follow-up.

METHODS

Patients older than 60, with transverse patellar fracture, type 34-C1 according to the AO/OTA classification system, referred to our trauma centre, between January 2014 and December 2017 were prospectively recruited. All the patients were managed using MIOT surgical procedure and underwent a clinical and radiological follow-up at 2 weeks, 6 weeks and at 3, 6, 12 and 15 months postoperatively. The clinical evaluation was performed using the Lysholm Knee Scoring System (LKSS) and the Visual Analogue Scale (VAS) for pain. The hardware removal was planned at 12-months follow-up. The paired t-test was performed. The test was two-tailed with a confidence level of 5%.

RESULTS

61 patients were recruited. The mean VAS was significantly lower in MIOT group until the 3-months follow-up (p = 0.001). ROM in flexion and LKSS score were significantly better in MIOT-group at all follow-ups, whereas ROM in extension showed no differences, between the two groups, starting from the 6-months follow-up. In the open surgery group, a significantly higher rate of delayed wound healing (p = 0.014), broken wires (p = 0.001) and non-cosmetic scar (p = 0.0221) was observed.

CONCLUSIONS

This prospective study shows that MIOT is a safe option for treatment of patellar transverse fractures in elderly patients, since it reduces the intra-operative blood loss, shortens the operating time, and is endowed with lower rates of postoperative complications.

Scoring systems for Oral Lichen Planus used by differently experienced raters

Background

Scoring systems have been widely used to evaluate the severity and activity of oral lichen planus (OLP). The aim of the present study was to compare two existing (one modified) scoring systems in the evaluation of OLP severity and correlation with pain. Three differently experienced raters were involved.

Material and Methods

Consecutive patients with OLP were assessed for pain using the Visual Analogue Scale and examined at 10 intraoral sites before starting (T0) and three weeks after (T1) steroid therapy (Clobetasol). Three differently experienced raters evaluated photographs using two scoring systems designated White-Erosive-Atrophic (WEA) modified from an older WEA system (WEA-MOD) and Reticular-erythematous-Ulcerative (REU) systems. WEA-MOD Kendall’s W and interclass correlation coefficient were calculated and correlation between REU/WEA-MOD and pain was calculated using Spearman coefficient.

Results

Most patients showed lesions on buccal mucosa (85-93,5%) and maxillary/mandibular gingivae (31,8-31,2%), predominantly reticular. At T0, Kendall-W coefficients of 0.89 and 0.74 were obtained for the REU and WEA respectively. At T1, Kendall-W coefficients of 0.83 and 0.58 were obtained for the REU and WEA respectively. Interclass correlation coefficient ranged from 0.87 to 0.90 for REU and from 0.58 to 0.87 for WEA. REU and WEA scores significantly decreased after therapy (p<0.000) as well as VAS (p<0.05). REU score showed correlation with VAS.

Conclusions

All the raters achieved comparable measures using REU whereas WEA and WEA-MOD seem less reproducible. REU seems to correlate to disease activity and pain.

Key words:Oral lichen planus, scoring system, VAS, REU, WEA, rater.

Epidemiology and variables involved in dental abscess: survey of dental emergency unit in Trieste

OBJECTIVES

The objective of this epidemiologic study was to estimate the healing time of acute dental abscesses and to evaluate the main variables involved in the healing process itself.

SUBJECTS AND METHODS

Among a sample of over 24 000 patients visited at the emergency dental unit, 688 subjects were diagnosed with dental abscess and enrolled in the study. Case histories of all patients were collected to investigate the clinical course and healing time of dental abscess according to anamnestic and diagnostic data and therapeutic management. A multiple logistic regression model was performed to evaluate the association of each variable with the healing time required for dental abscess.

RESULTS

Variables associated with increased healing time were spring seasonality at admission, pyretic state, trismus, involvement of multiple anatomic spaces, and spontaneous drainage. Moreover, administration of some, but not all, classes of antibiotics was also associated with an increased healing time.

CONCLUSIONS

The knowledge of variables involved in healing time for dental abscess is crucial in the optimization of managing such infections in terms of cost-benefit ratio. This would represent a valuable way to ensure a shortened and more effective healing.

Oral manifestation upon short time cocaine abuse. A case report

Effects of cocaine abuse on the oral mucosa are still poorly defined. Herein, a case of an 18-year-old male patient with a 15-day history of persistent painful ulcers and aphthous lesions of unknown etiology and with no other remarkable manifestations, is presented. All of the laboratory tests performed showed to be within normal ranges. Only subsequently, the patient admitted a cocaine abuse, through smoking and rubbing, over the last 15 days. Finally, after 15 days of interruption of cocaine abuse the oral lesions showed complete regression.

Using evidence from nanocavities to assess the vibrational properties of external surfaces

Internal surfaces of nanocavities are an exceptionally useful laboratory wherein one can spotlight the factors ruling the intricate interplay between morphology and chemistry at silicon surfaces. At the same time, they offer unparalleled opportunities to validate the assignment of vibrational signals of silicon-terminating species under almost ideal experimental conditions. In the case of hydrogen, evidence will be provided of the detailed evolution of H-related species at surfaces depending on their orientation. Also, preliminary results concerning nitrogen at and around nanocavity surfaces will be reported.

Acneiform rash due to epidermal growth factor receptor inhibitors: high-level laser therapy as an innovative approach

Acneiform rash associated with epidermal growth factor receptor inhibitors frequently presents facial manifestations. The treatment modality for such lesions still needs to be elucidated. The aim of this original report was to evaluate the effectiveness of high-level laser therapy in reducing the severity of facial acneiform rash induced by cetuximab, an epidermal growth factor receptor inhibitors. Four patients with metastatic colorectal cancer and two patients with head and neck cancer showing cetuximab-induced facial rash were treated by high-level laser therapy in two 8-min-long consecutive sessions/day over a 4-day treatment. Patients wore protective glasses to prevent eye damage related to laser light. Subsequently, patients were seen once a week for up to 21 days and after 180 days. During each day of treatment and each follow-up recall, patients were asked to complete a questionnaire about the onset and progression of their acneiform rash (for a total of eight sessions). Cetuximab-related toxicity and general discomfort visual analogue scales were also recorded in each of these eight sessions in the treated and control areas in each patient. After the fourth session of high-level laser therapy, the patients showed a noteworthy decrease in both cetuximab-related toxicity and visual analogue scales, up to a complete regression of the lesions at the end of the follow-up in all treated areas. The high-level laser therapy was effective in the healing of acneiform rash associated with epidermal growth factor receptor inhibitors with no side effects.

Phase Formation and Kinetic Processes in Silicide Growth

Twenty years of research have now been devoted to investigating reaction products obtained by annealing metal-layer/silicon structures. A wide variety of cases have been analyzsed and a considerable amount of data has been produced. Despite the vast amount of information available, several aspects concerning phase formation and kinetic processes are not yet well established. The purpose of this paper is to investigate the mechanisms of phase formation and to show the importance of kinetic factors in the appearance of various compounds. Results will be shown for a single metal layer deposited on silicon, for bilayers. and for alloys. Depending upon the starting structure, metal-rich or silicon-rich silicides can be formed. Moreover, by modifying the boundary conditions, it is possible to change the growth kinetics of the silicide phase that forms.

Structural And Compositional Modifications of III–V Ternary and Quaternary Compounds Induced by Ion Bombardment

The effect of low energy (0.5 to 5 keV) Ar+ beams on the surface structure and composition of monocrystalline ternary In0.53Ga0.47As and quaternary In0.70Ga0.30As0.64P0.36 films epitaxially grown by MO-VPE on InP (100) substrate has been investigated. Quantitative Auger electron spectroscopy has been used with the elemental standard method taking into account the electron diffraction effects. For both semiconductors, the outermost surface layer has been found to be Ga and In enriched. In the subsurface region, the Ga enrichment is even larger, at the expense of As and In. In the quaternary film, P is depleted in the surface as well in the subsurface region. Angular Resolved Auger Electron Spectroscopy is applied to the structural study of the sputter-etched surface. The nature and spatial extension of the ion-induced surface damage have been investigated at different energies, and doses of the primary ion beam. Is has been found that the resistance to the amorphization is strongly enhanced in InGaAs with respect to GaAs.

Oxygen-conserving reflexes of the brain: the current molecular knowledge

The trigemino-cardiac reflex (TCR) may be classified as a sub-phenomenon in the group of the so-called 'oxygen-conserving reflexes'. Within seconds after the initiation of such a reflex, there is neither a powerful and differentiated activation of the sympathetic system with subsequent elevation in regional cerebral blood flow (CBF) with no changes in the cerebral metabolic rate of oxygen (CMRO(2)) or in the cerebral metabolic rate of glucose (CMRglc). Such an increase in regional CBF without a change of CMRO(2) or CMRglc provides the brain with oxygen rapidly and efficiently and gives substantial evidence that the TCR is an oxygen-conserving reflex. This system, which mediates reflex protection projects via currently undefined pathways from the rostral ventrolateral medulla oblongata to the upper brainstem and/or thalamus which finally engage a small population of neurons in the cortex. This cortical centre appears to be dedicated to reflexively transduce a neuronal signal into cerebral vasodilatation and synchronization of electrocortical activity. Sympathetic excitation is mediated by cortical-spinal projection to spinal pre-ganglionic sympathetic neurons whereas bradycardia is mediated via projections to cardiovagal motor medullary neurons. The integrated reflex response serves to redistribute blood from viscera to brain in response to a challenge to cerebral metabolism, but seems also to initiate a preconditioning mechanism. Better and more detailed knowledge of the cascades, transmitters and molecules engaged in such endogenous (neuro) protection may provide new insights into novel therapeutic options for a range of disorders characterized by neuronal death and into cortical organization of the brain.

Hypoplasia and neuronal immaturity of the hypoglossal nucleus in sudden infant death

OBJECTIVE

To report the case of five month old female baby with a history of episodes of gastro-oesophageal reflux and pneumonia. Her sudden death offered a unique insight into the possible role of delayed neuronal maturation and hypoplasia of the hypoglossal nucleus in representing a likely morphological substrate of sudden death.

METHODS

Morphometric analysis was carried out with an Image-Pro Plus Image analyser (Media Cybernetics) on both sides of the brain stem.

RESULTS

Hypoplasia and neuronal immaturity of the hypoglossal nucleus were demonstrated, accompanied by hypoplasia of the arcuate nucleus.

CONCLUSIONS

Much attention should be paid to the possible role of the hypoglossal nucleus in determining a lethal outcome in infancy through impairment of deglutition and subsequent recurrent episodes of pneumonia, and as a necropsy finding.

Cosmetic bilateral leg lengthening: experience of 54 cases

The Ilizarov method for leg lengthening was used for cosmetic reasons in 54 patients with constitutional short stature. A mean lengthening of 7 cm with a low rate of complications produced an excellent or good outcome in all the patients, including improvement in psychological disturbances related to short stature. Those who undergo the procedure must be highly motivated, fully informed and understand the technique and possible complications. We suggest that the Ilizarov method for cosmetic limb lengthening is a technique without major complications. However, it requires careful follow-up, and the involvement of orthopaedic surgeons who are familiar with use of the circular frame and are experienced in limb lengthening and correction of deformity for pathological conditions.

Sudden infant death triggered by dive reflex

The dive reflex is the reflex mechanism most frequently considered in the aetiopathogenesis of sudden infant death syndrome (SIDS). This seems to persist in human beings as an inheritance from diver birds and amphibians. It has been reported that washing the face with cold water or plunging into cold water can provoke cardiac deceleration through the intervention of the ambiguus and the vagal dorsal nuclei. This report describes a case of SIDS that offers a unique insight into the role of the dive reflex in determining a lethal outcome. Examination of the brainstem on serial sections revealed severe bilateral hypoplasia of the arcuate nucleus and gliosis of the other cardiorespiratory medullary nuclei. The coronary and cardiac conduction arteries presented early atherosclerotic lesions. The possible role of parental cigarette smoking in the pathogenesis of arcuate nucleus hypoplasia and early coronary atherosclerotic lesions is also discussed.

Autoptic examination in sudden infant death syndrome and sudden intrauterine unexpected death: proposal of a national law

The autoptic procedures in sudden infant death syndrome (SIDS) and sudden intrauterine unexpected death (SIUD) victims requires an in-depth examination of the autonomic nervous system, central and peripheral, as well as of the cardiac conduction system. In these pathologies, our studies have identified frequent developmental abnormalities in the brain stem, particularly hypoplasia of the arcuate nucleus, and accessory atrioventricular pathways in the cardiac conduction system. The law 'Post-mortem Investigation on the SIDS and of Unexplained Late Fetal Death' designated the Institute of Pathology of Milan University as the National Reference Center. The objectives of this law include, in article 4, widespread informative and preventive campaigns and continuous formation of programs for medical personnel.

Role of somatostatin and apoptosis in breathing control in sudden perinatal and infant unexplained death

OBJECTIVES

To obtain basic information about the expression of somatostatin in the human central nervous system and, in particular, to evaluate its possible involvement in unexplained perinatal and in sudden infant death syndrome.

MATERIAL

Sixty-seven brainstems from subjects aged from 30 gestational weeks to 12 postnatal months, dying of both known and unknown causes, were selected for this study. The unexplained deaths included 17 sudden intrauterine deaths, 5 sudden neonatal deaths and 28 sudden infant deaths.

METHOD

All brainstems were fixed in 10% phosphate-buffered formalin, processed and embedded in paraffin, according to our protocol available on the web site: http://users.unimi.it/-pathol/sids/riscontro_diagnostico_e.html. The distribution of the somatostatin in the brainstem was studied by immunohistochemistry on serial sections.

RESULTS

We observed an intense somatostatin positivity in many brainstem nuclei prevalently involved in the respiratory activity (parabrachial/Kölliker-Fuse complex, locus coeruleus, hypoglossus nucleus, dorsal vagus motor nucleus, tractus solitarii nucleus, ambiguus nucleus, reticular formation) in stillbirths. In 10 fetuses with unexplained death the neurons of the hypoglossus nucleus were somatostatin-negative. In the postnatal deaths, we observed immunopositivity in the ventrolateral and ventral subnuclei of the tractus solitarii nucleus. Besides, in 15 sudden infant death victims and in 1 control case, somatostatin-positive neurons were also present in the hypoglossus nucleus. In 10 of these 15 cases, a high apoptotic index was also reported.

CONCLUSIONS

We suggest that abnormalities in the distribution of SS in the hypoglossus nucleus before and after birth may contribute to the induction of both fatal breathing in prenatal life and abnormal ventilatory control after birth leading to irreversible apnea.

Intimal preatherosclerotic thickening of the coronary arteries in human fetuses of smoker mothers

BACKGROUND

Many studies have described the development of preatherosclerotic coronary artery lesions in infancy. The observations reported in the literature regarding the fetal origin of coronary artery lesions are rare and controversial.

OBJECTIVES

To identify the features of preatherosclerotic coronary artery lesions in late fetal stillborns and the possible atherogenic role of maternal cigarette smoking. METHODS; We examined 22 stillborns (13 males and nine females), all of whom had died sine causa after the 32nd week of gestation. All underwent autopsy. Twelve of the mothers smoked over five cigarettes per day before and during the pregnancy. The four major epicardial coronary arteries were isolated along their whole length, embedded in paraffin and serially cut for histologic examination and immunohistochemical studies, particularly searching for the proliferating cell nuclear antigen and c-Fos expression. Alterations of chromosome 7 were also investigated by the fluorescence in situ hybridization technique.

RESULTS

In over 50% of the fetuses, almost all from smoker mothers, multifocal structural alterations of coronary walls were evident. The smooth muscle cells (SMCs) presented loss of polarity, forming columns perpendicular to the axis of the media and infiltrating the subendothelial connective tissue. Increased amounts of mucoid ground substance were also observed in the subendothelial connective tissue. In all the cases with coronary alterations, study of the biological markers showed intense c-Fos positivity of the SMCs.

CONCLUSIONS

Preatherosclerotic intimal alterations of the coronary arteries are already detectable in the prenatal period and are significantly associated with maternal cigarette smoking.

Expression of apoptosis and proliferating cell nuclear antigen (PCNA) in the cardiac conduction system of crib death (SIDS)

Aim of this study is to determine the expression of apoptosis and Proliferating Cell Nuclear Antigen (PCNA) in the cardiac conduction system in crib death and explained death (ED) cases. Postnatal morphogenesis of the conducting tissue is an important part of its normal development. In the atrio-ventricular node (AVN) and His bundle (HB) it consists of degeneration, cell death and replacing in an orderly programmed way. However, its nature and its relation to crib death is not yet fully explained. Apoptosis and PCNA were investigated in 8 heart conduction systems of infants dying of crib death and in 3 conduction systems of infants dying of ED as controls. The cardiac conduction system was removed in two blocks: the first included the sino-atrial node (SAN) and the crista terminalis, the second contained the atrio-ventricular node (AVN), His bundle (HB), bifurcation, and bundle branches. In the conduction systems as well as in the common myocardium the PCNA Labeling Index (PCNA-LI) was found to be negative in all cases. The apoptotic indices (AI) in SIDS and in ED were found to have no statistically significant differences (p>0.05). The SAN, in both groups, showed an AI similar to the one detected in common myocardium. In almost all cases, TUNEL labeling was detected in peripheral region of the AVN, close to the atrial myocardium. The AI was higher in the AVN, HB and the initial tract of bundle branches than in the common myocardium (p<0.05; Student's t test).

Sudden Infant Death Syndrome (SIDS): a study of cardiac conduction system

The theory that Sudden Infant Death Syndrome (SIDS) may be related to lethal cardiac arrhythmias or heart block due to structural abnormalities of the conduction system is attractive and still of particular interest. We analyze 69 autopsied cases of SIDS (46 males and 23 females, infants ranging in age from 3 to 365 days) and 24 age-matched cases of explained death (ED) as controls (16 males and 8 females), infants who died from extracardiac cause (cerebral and respiratory). SIDS and ED groups were divided into three subgroups according to the age: (A) from 3 to 60 days; (B) from 61 to 120 days; (C) from 121 to 365 days. Histological observations were focused on the cardiac conduction system (CCS) which was examined on serial sections with the technique devised by one of the present authors (L. Rossi). The following findings were observed: resorptive degeneration (97.10% of SIDS, 75% of ED), His bundle dispersion (33. 33% of SIDS, 16.66% of ED), Mahaim fibers (21.73% of SIDS, 8.3% of ED), cartilaginous meta-hyperplasia (5.79% of SIDS, 4.16% of ED), persistent fetal dispersion (24.63% of SIDS, 16.66% of ED), intramural right bundle (20.29% of SIDS, 25% of ED), left sided His bundle (20.29% of SIDS and 8.3% of ED), hemorrhage of the atrio-ventricular junction (15.94% of SIDS), septation of the bifurcation (13.04% of SIDS), atrio-ventricular node (AVN) dispersion (7.24% of SIDS), sino-atrial node hypoplasia (5.79% of SIDS), Zahn node (1.45% of SIDS), His bundle hypoplasia (1.45% of SIDS), intramural left bundle (1.45% of SIDS), AVN dualism (2.89% of SIDS), and His bundle dualism (2.89% of SIDS, 4.16% of ED). Only the presence of resorptive degeneration was significantly higher in SIDS than in ED cases (p = 0.004). Regarding the subgroups, the only significant difference was the higher presence of intramural right bundle in SIDS-A than in SIDS-B (p = 0.01). Despite the non-specificity of most of these findings, we believe that these changes, associated with particular conditions and/or neurovegetative stimuli, could cause potentially malignant arrhythmias. These data suggest the need for an accurate approach and examination of the cardiac conduction system in all cases of sudden death in infancy